Counting the here-and-now costs of climate change

A review of Slow Burn: The Hidden Costs of a Warming World

Also published on Resilience.

R. Jisung Park takes us into a thought experiment. Suppose we shift attention away from the prospect of coming climate catastrophes – out-of-control wildfires, big rises in sea levels, stalling of ocean circulation currents – and we focus instead on the ways that rising temperatures are already having daily impacts on people’s lives around the world.

Might these less dramatic and less obvious global-heating costs also provide ample rationale for concerted emissions reductions?

Slow Burn by R. Jisung Park is published by Princeton University Press, April 2024.

Park is an environmental and labour economist at the University of Pennsylvania. In Slow Burn, he takes a careful look at a wide variety of recent research efforts, some of which he participated in. He reports results in several major areas: the effect of hotter days on education and learning; the effect of hotter days on human morbidity and mortality; the increase in workplace accidents during hotter weather; and the increase in conflict and violence as hot days become more frequent.

In each of these areas, he says, the harms are measurable and substantial. And in another theme that winds through each chapter, he notes that the harms of global heating fall disproportionately on the poorest people both internationally and within nations. Unless adaptation measures reflect climate justice concerns, he says, global heating will exacerbate already deadly inequalities.

Even where the effect seems obvious – many people die during heat waves – it’s not a simple matter to quantify the increased mortality. For one thing, Park notes, very cold days as well as very hot days lead to increases in mortality. In some countries (including Canada) a reduction in very cold days will result in a decrease in mortality, which may offset the rise in deaths during heat waves.

We also learn about forward mortality displacement, “where the number of deaths immediately caused by a period of high temperatures is at least partially offset by a reduction in the number of deaths in the period immediately following the hot day or days.” (Slow Burn, p 85) 

After accounting for such complicating factors, a consortium of researchers has estimated the heat-mortality relationship through the end of this century, for 40 countries representing 55 percent of global population. Park summarizes their results:

“The Climate Impact Lab researchers estimate that, without any adaptation (so, simply extrapolating current dose-response relationships into a warmer future), climate change is likely to increase mortality rates by 221 per 100,000 people. … But adaptation is projected to reduce this figure by almost two-thirds: from 221 per 100,000 to seventy-three per 100,000. The bulk of this – 78 percent of the difference – comes from higher incomes.” (pp 198-199)

Let’s look at these estimates from several angles. First, to put the lower estimate of 73 additional deaths per 100,000 people in perspective, Park notes an increase in mortality of this magnitude would be six times larger than the US annual death toll from automobile crashes, and roughly tw0-thirds the US death toll from COVID-19 in 2020. An increase in mortality of 73 per 100,000 is a big number.

Second, it seems logical that people will try to adapt to more and more severe heat waves. If they have the means, they will install or augment their air-conditioning systems, or perhaps they’ll buy homes in cooler areas. But why should anyone have confidence that most people will have higher incomes by 2100, and therefore be in a better position to adapt to heat? Isn’t it just as plausible that most people will have less income and less ability to spend money on adaptation?

Third, Park notes that inequality is already evident in heat-mortality relationships. A single day with average temperature of 90°F (32.2°C) or higher increases the annual mortality in South Asian countries by 1 percent – ten times the heat-mortality increase that the United States experiences. Yet within the United States, there is also a large difference in heat-mortality rates between rich and poor neighbourhoods.

Even in homes that have air-conditioning (globally, only about 30%), low-income people often can’t afford to run the air-conditioners enough to counteract severe heat. “Everyone uses more energy on very hot and very cold days,” Park writes. “But the poor, who have less slack in their budgets, respond more sparingly.” (p 191)

A study in California found a marked increase in utility disconnections due to delinquent payments following heat waves. A cash-strapped household, then, faces an awful choice: don’t turn up the air-conditioner even when it’s baking hot inside, and suffer the ill effects; or turn it up, get through one heat wave, but risk disconnection unless it’s possible to cut back on other important expenses in order to pay the high electric bill.

(As if to underline the point, a headline I spotted as I finished this review reported surges in predatory payday loans following extreme weather.)

The drastic adaptation measure of relocation also depends on socio-economic status. Climate refugees crossing borders get a lot of news coverage, and there’s good reason to expect this issue will grow in prominence. Yet Park finds that “the numerical majority of climate-induced refugees are likely to be those who do not have the wherewithal to make it to an international border.” (p 141) As time goes on and the financial inequities of global heating increase, it may be true that even fewer refugees have the means to get to another country: “recent studies find that gradually rising temperatures may actually reduce the rate of migration in many poorer countries.” (p 141)

Slow Burn is weak on the issue of multiple compounding factors as they will interact over several decades. It’s one thing to measure current heat-mortality rates, but quite another to project that these rates will rise linearly with temperatures 30 or 60 years from now. Suppose, as seems plausible, that a steep rise in 30°C or hotter days is accompanied by reduced food supplies due to lower yields, higher basic food prices, increased severe storms that destroy or damage many homes, and less reliable electricity grids due to storms and periods of high demand. Wouldn’t we expect, then, that the 73-per-100,000-people annual heat-related deaths estimated by the Climate Impact Lab would be a serious underestimate?

Park also writes that due to rising incomes, “most places will be significantly better able to deal with climate change in the future.” (p 229) As for efforts at reducing emissions, in Park’s opinion “it seems reasonable to suppose that thanks in part to pledged and actual emissions cuts achieved in the past few decades, the likelihood of truly disastrous warming may have declined nontrivially.” (p 218) If you don’t share his faith in economic growth, and if you lack confidence that pledged emissions cuts will be made actual, some paragraphs in Slow Burn will come across as wishful thinking.

Yet on the book’s two primary themes – that climate change is already causing major and documentable harms to populations around the world, and that climate justice concerns must be at the forefront of adaptation efforts – Park marshalls strong evidence to present a compelling case.

A road map that misses some turns

A review of No Miracles Needed

Also published on Resilience

Mark Jacobson’s new book, greeted with hosannas by some leading environmentalists, is full of good ideas – but the whole is less than the sum of its parts.

No Miracles Needed, by Mark Z. Jacobson, published by Cambridge University Press, Feb 2023. 437 pages.

The book is No Miracles Needed: How Today’s Technology Can Save Our Climate and Clean Our Air (Cambridge University Press, Feb 2023).

Jacobson’s argument is both simple and sweeping: We can transition our entire global economy to renewable energy sources, using existing technologies, fast enough to reduce annual carbon dioxide emissions at least 80% by 2030, and 100% by 2050. Furthermore, we can do all this while avoiding any major economic disruption such as a drop in annual GDP growth, a rise in unemployment, or any drop in creature comforts. But wait – there’s more! In so doing, we will also completely eliminate pollution.

Just don’t tell Jacobson that this future sounds miraculous.

The energy transition technologies we need – based on Wind, Water and Solar power, abbreviated to WWS – are already commercially available, Jacobson insists. He contrasts the technologies he favors with “miracle technologies” such as geoengineering, Carbon Capture Storage and Utilization (CCUS), or Direct Air Capture of carbon dioxide (DAC). These latter technologies, he argues, are unneeded, unproven, expensive, and will take far too long to implement at scale; we shouldn’t waste our time on such schemes.  

The final chapter helps to understand both the hits and misses of the previous chapters. In “My Journey”, a teenage Jacobson visits the smog-cloaked cities of southern California and quickly becomes aware of the damaging health effects of air pollution:

“I decided then and there, that when I grew up, I wanted to understand and try to solve this avoidable air pollution problem, which affects so many people. I knew what I wanted to do for my career.” (No Miracles Needed, page 342)

His early academic work focused on the damages of air pollution to human health. Over time, he realized that the problem of global warming emissions was closely related. The increasingly sophisticated computer models he developed were designed to elucidate the interplay between greenhouse gas emissions, and the particulate emissions from combustion that cause so much sickness and death.

These modeling efforts won increasing recognition and attracted a range of expert collaborators. Over the past 20 years, Jacobson’s work moved beyond academia into political advocacy. “My Journey” describes the growth of an organization capable of developing detailed energy transition plans for presentation to US governors, senators, and CEOs of major tech companies. Eventually that led to Jacobson’s publication of transition road maps for states, countries, and the globe – road maps that have been widely praised and widely criticized.

In my reading, Jacobson’s personal journey casts light on key features of No Miracles Needed in two ways. First, there is a singular focus on air pollution, to the omission or dismissal of other types of pollution. Second, it’s not likely Jacobson would have received repeat audiences with leading politicians and business people if he challenged the mainstream orthodox view that GDP can and must continue to grow.

Jacobson’s road map, then, is based on the assumption that all consumer products and services will continue to be produced in steadily growing quantities – but they’ll all be WWS based.

Does he prove that a rapid transition is a realistic scenario? Not in this book.

Hits and misses

Jacobson gives us brief but marvelously lucid descriptions of many WWS generating technologies, plus storage technologies that will smooth the intermittent supply of wind- and sun-based energy. He also goes into considerable detail about the chemistry of solar panels, the physics of electricity generation, and the amount of energy loss associated with each type of storage and transmission.

These sections are aimed at a lay readership and they succeed admirably. There is more background detail, however, than is needed to explain the book’s central thesis.

The transition road map, on the other hand, is not explained in much detail. There are many references to scientific papers in which he outlines his road maps. A reader of No Miracles Needed can take Jacobson’s word that the model is a suitable representation, or you can find and read Jacobson’s articles in academic journals – but you don’t get the needed details in this book.

Jacobson explains why, at the level of a device such as a car or a heat pump, electric energy is far more efficient in producing motion or heat than is an internal combustion engine or a gas furnace. Less convincingly, he argues that electric technologies are far more energy-efficient than combustion for the production of industrial heat – while nevertheless conceding that some WWS technologies needed for industrial heat are, at best, in prototype stages.

Yet Jacobson expresses serene confidence that hard-to-electrify technologies, including some industrial processes and long-haul aviation, will be successfully transitioning to WWS processes – perhaps including green hydrogen fuel cells, but not hydrogen combustion – by 2035.

The confidence in complex global projections is often jarring. For example, Jacobson tells us repeatedly that the fully WWS energy system of 2050 “reduces end-use energy requirements by 56.4 percent” (page 271, 275).1 The expressed precision notwithstanding, nobody yet knows the precise mix of storage types, generation types, and transmission types, which have various degrees of energy efficiency, that will constitute a future WWS global system. What we should take from Jacobson’s statements is that, based on the subset of factors and assumptions – from an almost infinitely complex global energy ecosystem – which Jacobson has included in his model, the calculated outcome is a 56% end-use energy reduction.

Canada’s Premiers visit Muskrat Falls dam construction site, 2015. Photo courtesy of Government of Newfoundland and Labrador; CC BY-NC-ND 2.0 license, via Flickr.

Also jarring is the almost total disregard of any type of pollution other than that which comes from fossil fuel combustion. Jacobson does briefly mention the particles that grind off the tires of all vehicles, including typically heavier EVs. But rather than concede that these particles are toxic and can harm human and ecosystem health, he merely notes that the relatively large particles “do not penetrate so deep into people’s lungs as combustion particles do.” (page 49)

He claims, without elaboration, that “Environmental damage due to lithium mining can be averted almost entirely.” (page 64) Near the end of the book, he states that “In a 2050 100 percent WWS world, WWS energy private costs equal WWS energy social costs because WWS eliminates all health and climate costs associated with energy.” (page 311; emphasis mine)

In a culture which holds continual economic growth to be sacred, it would be convenient to believe that business-as-usual can continue through 2050, with the only change required being a switch to WWS energy.

Imagine, then, that climate-changing emissions were the only critical flaw in the global economic system. Given that assumption, is Jacobson’s timetable for transition plausible?

No. First, Jacobson proposes that “by 2022”, no new power plants be built that use coal, methane, oil or biomass combustion; and that all new appliances for heating, drying and cooking in the residential and commercial sectors “should be powered by electricity, direct heat, and/or district heating.” (page 319) That deadline has passed, and products that rely on combustion continue to be made and sold. It is a mystery why Jacobson or his editors would retain a 2022 transition deadline in a book slated for publication in 2023.

Other sections of the timeline also strain credulity. “By 2023”, the timeline says, all new vehicles in the following categories should be either electric or hydrogen fuel-cell: rail locomotives, buses, nonroad vehicles for construction and agriculture, and light-duty on-road vehicles. This is now possible only in a purely theoretical sense. Batteries adequate for powering heavy-duty locomotives and tractors are not yet in production. Even if they were in production, and that production could be scaled up within a year, the charging infrastructure needed to quickly recharge massive tractor batteries could not be installed, almost overnight, at large farms or remote construction sites around the world.

While electric cars, pick-ups and vans now roll off assembly lines, the global auto industry is not even close to being ready to switch the entire product lineup to EV only. Unless, of course, they were to cut back auto production by 75% or more until production of EV motors, batteries, and charging equipment can scale up. Whether you think that’s a frightening prospect or a great idea, a drastic shrinkage in the auto industry would be a dramatic departure from a business-as-usual scenario.

What’s the harm, though, if Jacobson’s ambitious timeline is merely pushed back by two or three years?

If we were having this discussion in 2000 or 2010, pushing back the timeline by a few years would not be as consequential. But as Jacobson explains effectively in his outline of the climate crisis, we now need both drastic and immediate actions to keep cumulative carbon emissions low enough to avoid global climate catastrophe. His timeline is constructed with the goal of reducing carbon emissions by 80% by 2030, not because those are nice round figures, but because he (and many others) calculate that reductions of that scale and rapidity are truly needed. Even one or two more years of emissions at current rates may make the 1.5°C warming limit an impossible dream.

The picture is further complicated by a factor Jacobson mentions only in passing. He writes,

“During the transition, fossil fuels, bioenergy, and existing WWS technologies are needed to produce the new WWS infrastructure. … [A]s the fraction of WWS energy increases, conventional energy generation used to produce WWS infrastructure decreases, ultimately to zero. … In sum, the time-dependent transition to WWS infrastructure may result in a temporary increase in emissions before such emissions are eliminated.” (page 321; emphasis mine)

Others have explained this “temporary increase in emissions” at greater length. Assuming, as Jacobson does, that a “business-as-usual” economy keeps growing, the vast majority of goods and services will continue, in the short term, to be produced and/or operated using fossil fuels. If we embark on an intensive, global-scale, rapid build-out of WWS infrastructures at the same time, a substantial increment in fossil fuels will be needed to power all the additional mines, smelters, factories, container ships, trucks and cranes which build and install the myriad elements of a new energy infrastructure. If all goes well, that new energy infrastructure will eventually be large enough to power its own further growth, as well as to power production of all other goods and services that now rely on fossil energy.

Unless we accept a substantial decrease in non-transition-related industrial activity, however, the road that takes us to a full WWS destination must route us through a period of increased fossil fuel use and increased greenhouse gas emissions.

It would be great if Jacobson modeled this increase to give us some guidance how big this emissions bump might be, how long it might last, and therefore how important it might be to cumulative atmospheric carbon concentrations. There is no suggestion in this book that he has done that modeling. What should be clear, however, is that any bump in emissions at this late date increases the danger of moving past a climate tipping point – and this danger increases dramatically with every passing year.

1In a tl;dr version of No Miracles Needed published recently in The Guardian, Jacobson says “Worldwide, in fact, the energy that people use goes down by over 56% with a WWS system.” (“‘No miracles needed’: Prof Mark Jacobson on how wind, sun and water can power the world”, 23 January 2023)

 

Photo at top of page by Romain Guy, 2009; public domain, CC0 1.0 license, via Flickr.

Dreaming of clean green flying machines

Also published on Resilience

In common with many other corporate lobby groups, the International Air Transport Association publicly proclaims their commitment to achieving net-zero carbon emissions by 2050.1

Yet the evidence that such an achievement is likely, or even possible, is thin … to put it charitably. Unless, that is, major airlines simply shut down.

As a 2021 Nova documentary put it, aviation “is the high-hanging fruit – one of the hardest climate challenges of all.”2 That difficulty is due to the very essence of the airline business.

What has made aviation so attractive to the relatively affluent people who buy most tickets is that commercial flights maintain great speed over long distances. Aviation would have little appeal if airplanes were no faster than other means of transportation, or if they could be used only for relatively short distances. These characteristics come with rigorous energy demands.

A basic challenge for high-speed transportation – whether that’s pedaling a bike fast, powering a car fast, or propelling an airplane fast – is that the resistance from the air goes up with speed, not linearly but exponentially. As speed doubles, air resistance quadruples; as speed triples, air resistance increases by a factor of nine; and so forth.

That is one fundamental reason why no high-speed means of transportation came into use until the fossil fuel era. The physics of wind resistance become particularly important when a vehicle accelerates up to several hundred kilometers per hour or more.

Contemporary long-haul aircraft accommodate the physics in part by flying at “cruising altitude” – typically about 10,000 meters above sea level. At that elevation the atmosphere is thin enough to cause significantly less friction, while still rich enough in oxygen for combustion of the fuel. Climbing to that altitude, of course, means first fighting gravity to lift a huge machine and its passengers a very long way off the ground.

A long-haul aircraft, then, needs a high-powered engine for climbing, plus a large store of energy-dense fuel to last through all the hours of the flight. That represents a tremendous challenge for inventors hoping to design aircraft that are not powered by fossil fuels.

In Nova’s “The Great Electric Airplane Race”, the inherent problem is illustrated with this graphic:

graphic from Nova, “The Great Electric Airplane Race,” 26 May 2021

A Boeing 737 can carry up to 40,000 pounds of jet fuel. For the same energy content, the airliner would require 1.2 million pounds of batteries (at least several times the maximum take-off weight of any 737 model3). Getting that weight off the ground, and propelling it thousands of miles through the air, is obviously not going to work.

A wide variety of approaches are being tried to get around the drastic energy discrepancy between fossil fuels and batteries. We will consider several such strategies later in this article. First, though, we’ll take a brief look at the strategies touted by major airlines as important short-term possibilities.

“Sustainable fuel” and offsets

The International Air Transport Association gives the following roadmap for its commitment to net-zero by 2050. Anticipated emissions reductions will come in four categories:
3% – Infrastructure and operational efficiencies
13% – New technology, electric and hydrogen
19% – Offsets and carbon capture
65% – Sustainable Aviation Fuel

The tiny improvement predicted for “Infrastructure and operational efficiencies” reflects the fact that airlines have already spent more than half a century trying to wring the most efficiency out of their most costly input – fuel.

The modest emission reductions predicted to come from battery power and hydrogen reflects a recognition that these technologies, for all their possible strengths, still appear to be a poor fit for long-haul aviation.

That leaves two categories of emission reductions, “Offsets and carbon capture”, and “Sustainable Aviation Fuel”.

So-called Sustainable Aviation Fuel (SAF) is compatible with current jet engines and can provide the same lift-off power and long-distance range as fossil-derived aviation fuel. SAF is typically made from biofuel feedstocks such as vegetable oils and used cooking oils. SAF is already on the market, which might give rise to the idea that a new age of clean flight is just around the corner. (No further away, say, than 2050.)

Yet as a Comment piece in Nature* notes, only .05% of fuel currently used meets the definition of SAF.4 Trying to scale that up to meet most of the industry’s need for fuel would clearly result in competition for agricultural land. Since growing enough food to feed all the people on the ground is an increasingly difficult challenge, devoting a big share of agricultural production to flying a privileged minority of people through the skies is a terrible idea.5

In addition, it’s important to note that the burning of SAF still produces carbon emissions and climate-impacting contrails. The use of SAF is only termed “carbon neutral” because of the assumption that the biofuels are renewable, plant-based products that would decay and emit carbon anyway. That’s a dubious assumption, when there’s tremendous pressure to clear more forests, plant more hectares into monocultures, and mine soils in a rush to produce not only more food for people, but also more fuel for wood-fired electric generating stations, more ethanol to blend with gasoline, more biofuel diesel, and now biofuel SAF too. When SAF is scaled up, there’s nothing “sustainable” about it.

What about offsets? My take on carbon offsets is this: Somebody does a good thing by planting some trees. And then, on the off chance that these trees will survive to maturity and will someday sequester significant amounts of carbon, somebody offsets those trees preemptively by emitting an equivalent amount of carbon today.

Kallbekken and Victor’s more diplomatic judgement on offsets is this:

“The vast majority of offsets today and in the expected future come from forest-protection and regrowth projects. The track record of reliable accounting in these industries is poor …. These problems are essentially unfixable. Evidence is mounting that offsetting as a strategy for reaching net zero is a dead end.”6 (emphasis mine)

Summarizing the heavy reliance on offsetting and SAF in the aviation lobby’s net-zero plan, Kallbekken and Victor write “It is no coincidence that these ideas are also the least disruptive to how the industry operates today.” The IATA “commitment to net-zero”, basically, amounts to hoping to get to net-zero by carrying on with Business As Usual.

Contestants, start your batteries!

Articles appear in newspapers, magazines and websites on an almost daily basis, discussing new efforts to operate aircraft on battery power. Is this a realistic prospect? A particularly enthusiastic answer comes in an article from the Aeronautical Business School: “Electric aviation, with its promise of zero-emission flights, is right around the corner with many commercial projects already launched. …”7

Yet the electric aircraft now on the market or in prototyping are aimed at very short-haul trips. That reflects the reality that, in spite of intensive research and development in battery technology through recent decades, batteries are not remotely capable of meeting the energy and power requirements of large, long-haul aircraft.

The International Council on Clean Transportation (ICCT) recently published a paper on electric aircraft which shows why most flights are not in line to be electrified any time soon. Jayant Mukhopadhaya, one of the report’s co-authors, discusses the energy requirements of aircraft for four segments of the market. The following chart presents these findings: 

Table from Jayant Mukhopadhaya, “What to expect when expecting electric airplanes”, ICCT, July 14, 2022.

The chart shows the specific energy (“eb”, in Watt-hours per kilogram) and energy density (“vb”, in Watt-hours per liter) available in batteries today, plus the corresponding values that would be required to power aircraft in the four major market segments. Even powering a commuter aircraft, carrying 19 passengers up to 450 km, would require a 3-time improvement in specific energy of batteries.

Larger aircraft on longer flights won’t be powered by batteries alone unless there is a completely new, far more effective type of battery invented and commercialized:

“Replacing regional, narrowbody, and widebody aircraft would require roughly 6x, 9x, and 20x improvements in the specific energy of the battery pack. In the 25 years from 1991 to 2015, the specific energy and energy density of lithium-ion batteries improved by a factor of 3.”8

If the current rate of battery improvement were to continue for another 25 years, then, commuter aircraft carrying up to 19 passengers could be powered by batteries alone. That would constitute one very small step toward net-zero aviation – by the year 2047.

This perspective helps explain why most start-ups hoping to bring electric aircraft to market are targeting very short flights – from several hundred kilometers down to as little as 30 kilometers – and very small payloads – from one to five passengers, or freight loads of no more than a few hundred kilograms.

The Nova documentary “The Great Electric Airplane Race” took an upbeat tone, but most of the companies profiled, even if successful, would have no major impact on aviation’s carbon emissions.

Joby Aviation is touted as “the current leader in the race to fill the world with electric air taxis.” Their vehicles, which they were aiming to have certified by 2023, would carry a pilot and 4 passengers. A company called KittyHawk wanted to build an Electrical Vertical Take-Off and Landing (EVTOL) which they said could put an end to traffic congestion. The Chinese company Ehang was already offering unpiloted tourism flights, for two people and lasting no more than 10 minutes.

Electric air taxis, if they became a reality after 50 years of speculation, would result in no reductions in the emissions from the current aviation industry. They would simply be an additional form of energy-intensive mobility coming onto the market.

Other companies discussed in the Nova program were working on hybrid configurations. Elroy’s cargo delivery vehicle, for example, would have batteries plus a combustion engine, allowing it to carry a few hundred kilograms up to 500 km.

H2Fly, based in Stuttgart, was working on a battery/hydrogen hybrid. H2Fly spokesperson Joseph Kallo explained that “The energy can’t flow out of the [hydrogen fuel] cell as fast as it can from a fossil fuel engine or a battery. So there’s less power available for take-off. But it offers much more range.”

By using batteries for take-off, and hydrogen fuel cells at cruising altitude, Kallo said this technology could eventually work for an aircraft carrying up to 100 passengers with a range of 3500 km – though as of November 2020 they were working on “validating a range of nearly 500 miles”.

To summarize: electric and hybrid aviation technologies could soon power a few segments of the industry. As long as the new aircraft are replacing internal combustion engine aircraft, and not merely adding new vehicles on new routes for new markets, they could result in a small reduction in overall aviation emissions.

Yet this is a small part of the aviation picture. As Jayant Mukhopadhaya told treehugger.com in September,

“2.8% of departures in 2019 were for [flights with] less than 30 passengers going less than 200 km. This increases to 3.8% if you increase the range to 400 km. The third number they quote is 800 km for 25 passengers, which would then cover 4.1% of global departures.”9

This is roughly 3–4% of departures – but it’s important to recognize this does not represent 3–4% of global passenger km or global aviation emissions. When you consider that the other 96% of departures are made by much bigger planes, carrying perhaps 10 times as many passengers and traveling up to 10 times as far, it is clear that small-plane, short-hop aviation represents just a small sliver of both the revenue base and the carbon footprint of the airline industry.

Short-haul flights are exactly the kind of flights that can and should be replaced in many cases by good rail or bus options. (True, there are niche cases where a short flight over a fjord or other impassable landscape can save many hours of travel – but that represents a very small share of air passenger km.)

If we are really serious about a drastic reduction in aviation emissions, by 2030 or even by 2050, there is just one currently realistic route to that goal: we need a drastic reduction in flights.

* * *

Postscript: At the beginning of October a Washington Post article asked “If a Google billionaire can’t make flying cars happen, can anyone?” The article reported that KittyHawk, the EVTOL air taxi startup highlighted by Nova in 2021 and funded by Google co-founder Larry Page, is shutting down. The article quoted Peter Rez, from Arizona State University, explaining that lithium-ion batteries “output energy at a 50 times less efficient rate than their gasoline counterparts, requiring more to be on board, adding to cost and flying car and plane weight.” This story underscores, said the Post, “how difficult it will be to get electric-powered flying cars and planes.”

*Correction: The original version of this article attributed quotes from the Nature Comment article simply to “Nature”. Authors’ names have been added to indicate this is a signed opinion article and does not reflect an official editorial position of Nature.

Footnotes

1 IATA, “Our Commitment to Fly Net Zero by 2050”.

2 Nova, “The Great Electric Airplane Race” – 26 May 2021.

3 “The Difference In Weight Between The Boeing 737 Family’s Many Variants”, by Mark Finlay, April 24, 2022.

4  Steffen Kallbekken and David G. Victor, Nature, “A cleaner future for flight — aviation needs a radical redesign”, 16 September 2022.

5 Dan Rutherford writes, “US soy production contributes to global vegetable oil markets, and prices have spiked in recent years in part due to biofuel mandates. Diverting soy oil to jet fuel would put airlines directly in competition with food at a time when consumers are being hammered by historically high food prices.” In “Zero cheers for the supersoynic renaissance”, July 11, 2022.

6 Kallbekken and Victor, Nature, “A cleaner future for flight — aviation needs a radical redesign”, 16 September 2022.

7 “The path towards an environmentally sustainable aviation”, by Óscar Castro, March 23, 2022.

8 Jayant Mukhopadhaya, “What to expect when expecting electric airplanes”, ICCT, July 14, 2022.

9 “Air Canada Electrifies Its Lineup With Hybrid Planes”, by Lloyd Alter, September 20, 2022.


Photo at top of page: “Nice line up at Tom Bradley International Terminal, Los Angeles, November 10, 2013,” photo by wilco737, Creative Commons 2.0 license, on flickr.

Inequality, the climate crisis, and the frequent flier

ALSO PUBLISHED ON RESILIENCE

If we are to make rapid progress in reducing carbon emissions, and do so in an equitable way, does everybody need to give up flying?

No, not at all – because most people don’t fly anyway, and have never flown. And among those privileged enough to fly, only a small minority fly often.

If most people gave up flying that would have little impact on emissions – because most people fly seldom or never.

Yet major carbon emissions reductions need to happen within the next several years. That’s much faster than any revolutionary new aviation technologies can be developed, let alone rolled out on a large scale. The way to dramatically and quickly reduce aviation emissions is as simple as it is obvious: the small minority of people who fly frequently should give up most of their airline journeys.

We can see clearly where rapid progress might be made when we recognize the tight correlation between global wealth control and global emissions.

On a global scale, and also within most individual countries, both income and wealth is dramatically skewed in favour of a small percentage of the population.

In the same fashion, carbon dioxide emissions are dramatically skewed, as an overwhelming share of the emissions causing the climate crisis are due to the lifestyles of a small proportion of the population.

A relatively affluent minority of the world’s population takes nearly all of the world’s aviation journeys, and within that minority, a small percentage of people take by far the most flights.

Within that wealthiest and most polluting sliver of the world’s population, flying typically accounts for the biggest share of their generally outsize contributions to the climate crisis. Meaning, if they are to reduce their emissions to a level consistent with international climate accords, they will need to change their flying from a frequent, routine practice into a rare, exceptional practice, or cease from flying at all.

Yet in all the sectors that combine to steer our industrial societies, the people that have a significant share of influence typically belong to the frequent fliers club. That is true throughout the corporate world, in major news and entertainment media, in academia, in nearly every level of government in affluent countries, and among the socio-economic elites in non-affluent countries. In all these social sectors, it has become routine over the past 50 years to get on a plane and fly to some formerly distant place multiple times a year, whether for business or for leisure.

The preceding paragraphs outline a daunting list of topics to try to cover in one blog post. We’ll have help from some very useful graphs. Here goes ….

Follow the money

Since flying is an expensive habit, even in monetary terms, we would expect that most flying is done by the people with the most money. Here’s one way of visualizing who has the money:

Global income and wealth inequality, from the World Inequality Report 2022, by Lucas Chancel (lead author), Thomas Piketty, Emmanuel Saez, and Gabriel Zucman, page 10.

As the chart above indicates, money is overwhelmingly concentrated in the hands of a small percentage of the global population – wealth is heavily skewed by class. And as the chart below indicates, money-making activities are overwhelmingly concentrated in some countries – wealth is heavily skewed by geography.

GDP per capita for selected regions and countries, 2010 – 2020, graph from Our World In Data based on World Bank data. The world average for 2020 was $16,608, while GDP per capita in wealthy countries was from 2.5 to about 4 times as high.

Ready for a surprise? You never woulda guessed, but carbon emissions are skewed in roughly the same ways.

Global Carbon Inequality, 2019, from the World Inequality Report 2022, by Lucas Chancel (lead author), Thomas Piketty, Emmanuel Saez, and Gabriel Zucman, page 18.

 

Per capita emissions across the world, 2019, from the World Inequality Report 2022, by Lucas Chancel (lead author), Thomas Piketty, Emmanuel Saez, and Gabriel Zucman, page 19.

The “Global Carbon Inequality” chart tells us that one half of global population are responsible for only a small share, 12%, of global warming emissions. The other half are responsible for 88% of global warming emissions. And just 10% of the population are responsible for nearly half the emissions.

The “Per capita emissions across the world” shows the dramatic variance in emission levels from various geographic regions. It might come as no surprise that both the top 10% and the middle 40% groups in North America leave most of their international rivals in a cloud of fossil fuel smoke, so to speak. Those who are modestly well off, or rich, in the US and Canada tend to live in big houses; drive, a lot, in big cars or “light trucks”; and travel by air frequently.

And in all areas of the world, the top 10% of emitters have per capita emissions far in excess of the middle 40% or lower 50% groups.

What does this mean for our collective hopes of slowing down the accelerating climate crisis? It means that most of the emission reductions must come from a relatively small share of the global population – particularly from the top 10% on a global scale, and to a lesser but still significant extent from the middle 40% within wealthy countries.

Consider this chart from the World Inequality Report.

Per capita emissions reduction requirements, US & France, from the World Inequality Report 2022, by Lucas Chancel (lead author), Thomas Piketty, Emmanuel Saez, and Gabriel Zucman, page 128.

If we were to meet the emissions reduction targets set out for 2030 in the Paris Agreement in a fair and equitable way, the top 10% of people in the US would need to reduce their carbon footprints by 87%, and the middle 40% would need to reduce their carbon footprints by 54%. The lower 50% of the US population could actually increase their carbon footprints by 3% while being consistent with the Paris Agreement – if, that is, the upper 50% actually carried their fair share of the changes needed.

The story is much the same in France, with dramatic per capita emissions reductions needed from the top 50%.

For India and China, as shown below, the picture is significantly different.

Per capita emissions reduction requirements, India & China, from the World Inequality Report 2022, by Lucas Chancel (lead author), Thomas Piketty, Emmanuel Saez, and Gabriel Zucman, page 129.

In both India and China, the upper 10% would need to dramatically reduce their carbon footprints to be consistent with the Paris Agreement. However, both the middle 40% and the lower 50% in those countries could dramatically increase their carbon footprints in the next eight years, if the Paris Agreement targets were not only to be met, but met in an equitable way.

Imagine for a moment that the small minority of people with large carbon footprints, both globally and within countries, made a serious effort at reducing those footprints. What aspect of their lifestyles would be the most logical place to start?

Here, after what might have seemed like a long detour, we get back to the airport.

Panorama from inside Edinburgh air traffic control room, Oct 2013, photo by NATS – UK Air Traffic Control, licensed via CC BY-NC-ND 2.0, accessed on Flickr.

A high-level view

In spite of steep increases in aviation emissions in recent decades, direct emissions from aviation are still a small slice of overall global warming emissions. At the same time, among the world’s affluent classes, per capita emissions from aviation alone are much higher than the total per capita emissions of most people in much of the world.

The explanation lies here: only a small proportion of the world’s population flies at all, and among those, another small proportion takes most of the flights, the longest flights, and the flights that incur the largest per capita carbon footprints.

Even within high-income countries, less than half the population gets on a plane in a given year, according to a recent article in Global Environmental Change.

And on a global scale, Tom Otley reported in 2020,

“The research says that the share of the world’s population travelling by air in 2018 was just 11 per cent, with at most 4 per cent taking international flights.” (Business Traveller)

Can we conclude that 11 per cent of the people have an equal share of the aviation emissions? That would be deeply misleading, because most of those 11% take just the occasional flight, while a smaller number take many flights.

As reported in the article “A few frequent flyers ‘dominate air travel’” on BBC News, here’s how a small share of flyers in selected countries keep airports busy:

“In the UK, 70% of flights are made by a wealthy 15% of the population …. [I]n the US, just 12% of people take two-thirds of flights. … Canada: 22% of the population takes 73% of flights …. The Netherlands: 8% of people takes 42% of flights. … China: 5% of households takes 40% of flights. … India: 1% of households takes 45% of flights.”

But wait – there’s more! Stefan Gössling and Andreas Humpe explain in “The global scale, distribution and growth of aviation”, “The share of the fuel used by these [frequent] air travelers is likely higher, as more frequent fliers will more often travel business or first class ….”

Flying in more luxurious fashion comes at a huge environmental cost:

“The International Council on Clean Transportation (ICCT) (2014) estimates that the carbon footprint of flying business class, first class, or in a large suite is 5.3, 9.2 or 14.8 times larger than for flying in economy class.” (Gössling and Humpe)

Due to the frequency of their flights, plus the more luxurious seating accommodations often favoured by those who can afford many flights, about 10% of the most frequent fliers account for about half of all aviation emissions.

Gössling and Humpe refers to these most frequent fliers as “super emitters”, noting that “[S]uper emitters may contribute to global warming at a rate 225,000 times higher than the global poor” who have almost no carbon footprint.

To summarize: aviation accounts for a relatively small percentage of overall global warming emissions, because flying is a privilege enjoyed almost exclusively by a small percentage of the affluent classes. Yet among these classes, aviation results in a large share of personal carbon footprints, especially if flying is a regular occurrence.

Our World In Data states it starkly: “Air travel dominates a frequent traveller’s individual contribution to climate change.”

The same report adds, “The average rich person emits tonnes of CO2 from flying each year – this is equivalent to the total carbon footprint of tens or hundreds of people in many countries of the world.” (emphasis mine)

If we recall some figures from earlier in this post, those individuals in the US whose carbon footprints rank in the top 10% will need to reduce those footprints by 87%, for fair compliance with the Paris Agreement.

For most of those in the very-high-carbon-emissions bracket, a drastic reduction in flying will be a necessary, though not sufficient, lifestyle change in any future that includes climate justice.

• • •

Not so fast, frequent fliers might protest. Aren’t you overlooking the possibility, perhaps even the probability, that in the near future we will have a flourishing airline industry powered by clean electricity or clean hydrogen?

That’s too complicated a subject for a blog post that’s quite long enough already.

One recurring theme in this series has been the distinction between device-level changes and system-level changes. A speedy, safe, ocean-jumping airliner that burns no fossil fuel, if such an airliner were to exist, would be a great example of a device-level change.

I don’t expect to see such an airliner making commercially-viable trips within my lifetime. I’ll explain that skepticism in the next installment of this series on transportation.

Photo at top of page: Airbus airliners lined up at Chengdu, November 2015; photo by L.G. Liao, accessed at Wikimedia Commons.

Losing altitude

Travel as if every place matters.

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In my lifetime a curious habit has taken hold among a small minority of the earth’s residents. For this elite group the ability to get to nearly anywhere else on earth within 24 hours, give or take a few, has come to be regarded as normal, as an entitlement, as damn near a necessity.

In this new relationship with geography, there are only two places that matter: the place in which I get on an airplane, and the place where I get off. Intervening places don’t matter: they are not felt, they are not smelled, they are not heard, they are usually not even seen unless the sky is exceptionally clear and a remote landscape scrolls far beneath my window.

To be sure, this ability to ignore intervening distances has developed over a few centuries, but it is still a recent phenomenon. Through nearly all of human evolution, when we traveled we felt every hill and bump and wave along our journey. Even when some of us gained the status of travelling on horseback or perhaps even in a wheeled wagon, journeys were rough and not drastically faster than a human could go on foot. In going from A to B, then, we learned a lot about, and we felt some connection to, every place between A and B.

The construction of smoother roads made some difference, and the explosive development of railroads in the 19th century made a lot of difference. As speeds climbed far beyond any velocity in previous human experience, the journey also became smoother. It was still possible to have a relatively close look at the passing landscape, but it was on the other side of a window, and viewing it was optional. In the twentieth century societies where car culture took over, this strong separation of traveller from landscape became a fact of daily life.

It was air travel, though, that made a complete separation of person from landscape a possibility. At first it was a rare, novel, exciting sensation experienced by just a few. Even today most of the people in the world have never flown,1 and only a tiny minority fly regularly.2 But for the global elite – which includes a substantial part of the population of affluent countries – most travel kilometers are traversed in high-altitude, high-velocity cocoons that make all the earth, save two points, mere fly-over country.

In the next installment of this series we’ll consider the environmental impact of this strange new travel habit. In this installment I concentrate on the struggles some of us face when we ask, “Should I fly?”

We’ll start by asking: which of our journeys actually matter?

Why not? It doesn’t cost me much …

In today’s world a small elite takes multiple trips a year, turning vast energy resources into pollution, in journeys that don’t have a lot of value, even to themselves.

Is that an outrageous and unwarranted value judgement? Perhaps. But here’s how I arrive at that judgement.

Of all the long journeys made by air travellers today, how many would be made if the person had to walk, or get on a slow and risky sailing craft to cross a large body of water? How many would be made if people had to peddle a bicycle most or all of the way? How many would be made if the best option was a train topping out at 100 km and stopping frequently? How many would be made if the traveller had to drive, on a road network that took them through every city, town and village?

We can answer those questions simply by looking into our own histories. Most people made few long journeys when it took days, weeks or months for a one-way trip to their destination.

Certainly, some journeys are exceptionally important to the traveller. Someone might find it so meaningful to say goodbye to an aging parent in a distant country that they would give up months of their time to make the trip. For a few people, it is valuable to go to distant countries for purposes of trade, in spite of the cost in time and risk. For people in desperate socio-economic straits, a trip halfway around the world at great personal hardship and risk and with no guarantee of ever making a return trip, might be judged the best of their terrible options.

A small number of people would even make a few distant journeys just to “see the world” – though in the past such trips were necessarily long in time as well as in space.

But crossing an ocean just to take a short river cruise? Crossing an ocean just to visit a few museums and restaurants for a week or two? Crossing a continent just for a weekend sporting event, or to lie on a beach for several days? Most such journeys simply wouldn’t be made if they involved a week or a month of travel getting there and the same getting home. They simply aren’t that important.

Those of us in the upper half of the global privilege pyramid can make frequent long journeys because they don’t cost us much personally. Since the onset of mass air travel, our long journeys cost us almost none of our own time. There is a cost, perhaps even a significant cost, in our discretionary income, yes – but if we have discretionary income to begin with, we’re lucky enough to have money we can spend on things we don’t need.

Now, we might be aware that our long airline journeys do have costs to other people around the globe, already today and even more in the near future. We might be aware of the carbon emissions from an aircraft, and aware that the other emissions approximately double the global-warming impact of the CO2 emitted.3 We might be aware that although aviation has contributed only a small proportion of global warming pollution to date, that’s because only a small percentage of the world’s population do much or any flying. We might even be aware that if we make more than one long-haul flight per year, those flights are likely the largest contributor to our personal carbon footprint.

That awareness might make us question whether we should stop flying, completely and forever. And perhaps that thought makes us so uncomfortable that we push it away, at least long enough to get our next trip booked.

But “all or nothing” framings seldom lead to the best decision-making. Here’s my suggestion for deciding which trips are really important. Would I still choose to take a journey even if the travel time, forth and back, were weeks or months? Is it important enough that I would even seriously entertain the idea of giving up a large chunk of my own time? If the answer is “no, obviously not!” then I shouldn’t consider foisting the cost on others either – costs, that is, in the form of large amounts of carbon pollution.

Honestly grappling with those questions may not result in a complete cessation of long-distance travel, but it would result in a drastic reduction in casual continent-hopping.

What about “love miles”?

In a perceptive blog post entitled “How to Fly Less”, climate scientist Kimberly Nichols relates how the difficult barrier of “love miles” stalled her from making progress on much easier and more consequential ways of reducing the impact of her flying habit.

“Love miles” is a phrase used by George Monbiot in his 2006 book Heat. “Love miles” refers to those long distance trips, obviously of deep importance to most people, made to visit family members or dear friends across continents or across oceans.

For Kimberly Nichols, a US resident who moved to Sweden for a university position, the thought of giving up her once-a-year visits to her parents in California was too much to bear. Worse, that blocked her from thinking about all the flights she could do without. But when she was prompted to start with the easy issues, not the hard issues, she soon found she could eliminate most of her flying, while deeply appreciating overland trips much closer to her current home.

Her advice is so simple that it shouldn’t even need emphasis:

“Identify which flights you don’t need; cut those first. A recent study of frequent flyers found the travellers themselves rated only 58 percent of their trips “‘important” or “very important.’”4

In the category of “good advice which I myself didn’t follow”, she admonishes “Don’t move really far away from people you love!” Perhaps that sounds trite. But until the last few generations, people needed a very compelling reason to move a great distance away from family, and if they did, they had no expectation of having routine or annual visits with the family members they had left – travel time commitments were too large.

As for long-distance vacations – is the grass always greener on the other side of the world? What about all the great destinations much closer to home that you have only glimpsed from the window of a plane, if at all?

It is often said that travel opens people’s minds, that it broadens their perspectives. Ideally, yes. But I’m not convinced that the age of mass airline tourism has made people generally wiser, let alone happier or more content. What it has done, is given a small subset of the globe’s affluent classes a barely skin-deep acquaintance with dozens or scores of places and their inhabitants. And that, at great but unequally distributed cost to our shared environment.

Stratospheric heights, and a steep price

For now and for the near future, most of the life-altering and life-threatening costs of the climate crisis are being paid by those who have contributed the least to carbon emissions. The people who pay the biggest price don’t live in the tiny proportion of the globe represented by ski resorts, beach resorts, or the capitals of “civilization” such as London, Paris, Los Angeles, New York or Shanghai. Those who pay the highest price live in the rest of the globe, fly-over country for the frequent flyers.

The Global Inequality Report gives a particularly stark example of carbon emissions inequality: space tourism.

“An 11-minute flight [into space] emits no fewer than 75 tonnes of carbon per passenger once indirect emissions are taken into account (and more likely, in the 250-1,000 tonnes range). At the other end of the distribution, about one billion individuals emit less than one tonne per person per year. Over their lifetime, this group of one billion individuals does not emit more than 75 tonnes of carbon per person. It therefore takes a few minutes in space travel to emit at least as much carbon as an individual from the bottom billion will emit in her entire lifetime.”5

But how stark is the carbon emissions inequality for the more “average” frequent flier? We’ll take a more detailed look at inequality in the skies in the next installment of this series.

In the interest of honest disclosure, here is a brief summary of my own relationship to flying. I have never been a frequent flyer, and I’ve only taken two trips across an ocean. For most of my adult life I took most of my vacations by bike, but that often involved a plane trip for at least one leg of the journey. After becoming aware of the climate crisis and the role of aviation in that crisis, I consciously decided to minimize flying. In the past 10 years I have taken one one-way flight from Minneapolis to Toronto, and one one-way flight from London to Toronto. I have also become painfully aware of the terribly limited opportunities for train travel in North America as compared to train travel in Europe. Nevertheless, there are more great places in North America that can be reached by train than I will ever have time to visit.

Footnotes

1 “Less than 20 percent of the world’s population has ever taken a single flight” – former Boeing CEO David Muilenburg, cited in “The global scale, distribution and growth of aviation”,  by Stefan Gössling and Andreas Humpe, Global Environmental Change, November 2020.

2 “National surveys indicate that in high income countries, between 53% and 65% of the population will not fly in a given year.” – Gössling and Humpe, Global Environmental Change, November 2020.

3 To cite one source, a Yale Environment 360 article says this: “Though lasting for only a short time, these ‘contrails’ [condensation trails] have a daily impact on atmospheric temperatures that is greater than that from the accumulated carbon emissions from all aircraft since the Wright Brothers first took to the skies more than a century ago.” And further: “Civilian aircraft currently emit about 2 percent of anthropogenic CO2 and, once the effects of contrails are included, cause 5 percent of warming. But there is a key difference. While CO2 accumulates in the atmosphere and has a long-lasting effect, contrails last a matter of hours at most, and their warming impact is temporary.” (How Airplane Contrails Are Helping Make the Planet Warmer, by Fred Pierce, July 18, 2019.) If we rapidly shrink the aviation industry, the effects of contrails will quickly dwindle too. But if the airline industry continues to grow, contrails will help push the climate towards already close tipping points.

4 Data cited from “Can we fly less? Evaluating the ‘necessity’ of air travel”, Journal of Air Transport Management, October 2019.

5 World Inequality Report 2022, Coordinated by Lucas Chancel (Lead author), Thomas Piketty, Emmanuel Saez, Gabriel Zucman, page 134; emphasis mine.

Image at top of page: Airplane landing at Zurich airport, June 2018, photo by Michael Kuhn, accessed at Wikimedia Commons; cropped and resized.

Right-sizing delivery vehicles

Cargo bikes can replace far heavier vehicles for a substantial share of urban deliveries. But should you buy a cargo bike for personal use? Probably not.

ALSO PUBLISHED ON RESILIENCE.ORG

In North America we think in extreme terms when it comes to last-mile freight delivery. Whether the cargo is a couple of bags of groceries, a small parcel, a large-screen TV or a small load of lumber, we routinely dispatch vehicles with hundreds-of-horsepower engines.

This practice has never made sense, and there have always been niche markets where some products and parcels have been delivered by bicycle couriers instead of truck drivers. Historically, cargo bikes were in wide use in many cities in the decades before cars and trucks cemented their death grip on most urban traffic lanes.1

Today the cargo bike industry is growing rapidly due to several factors. Many cities are establishing zero-emissions zones. The cost of gasoline and diesel fuel has risen rapidly. Congested traffic means powerful expensive vehicles typically travel at bicycle-speed or slower in downtown areas. Last but not least, the development of low-cost, lightweight electric motors for small vehicles dramatically boosts the freight delivery capacity of e-assist bikes even in hilly cities.

Thousands of companies, from sole-proprietor outfits to multinational corporations, are now integrating cargo bikes into their operations. At the same time there is an explosion of new micro-powered vehicle designs on the market.2

Where a diesel-powered urban delivery van will have an engine with hundreds of horsepower, an electric-assist bike in the EU is limited to a motor of 250 W, or about one-third of one horsepower.3 Yet that small electric motor is enough to help a cyclist make typical parcel deliveries in many urban areas at a faster rate than the diesel van can manage.

A great many other deliveries are made, not by companies, but simply by individuals bringing their own purchases home from stores. In this category, too, North Americans tend to believe an SUV or pick-up truck is the obvious tool for the job. But in many car-clogged cities and suburbs a bicycle, whether electric-assist or not, is a much more appropriate tool for carrying purchases home from the store.

Image from pxhere.com, licensed via CC0 Public Domain.

This is an example of a change that can be made at the device level, rapidly, without waiting for system-level changes that will take a good bit longer. When it comes to reducing carbon emissions and reducing overall energy use, the rapid introduction and promotion of cargo bikes as delivery vehicles is an obvious place to make quick progress.

At the same time, the adoption of more appropriate delivery devices will become much more widespread if we simultaneously work on system-level changes. These changes can include establishing more and larger urban zero-emission zones; lowering speed limits for heavy vehicles (cars and trucks) on city streets; and rapid establishment of safe travel lanes for bikes throughout urban areas.

The environmental impact of deliveries

The exponential growth in online shopping over the past twenty years has also led to “the constant rise in the use of light commercial vehicles, despite every effort by cities and regulators to reduce congestion and transport emissions.”4

Last-mile urban delivery, notes the New York Times, “is the most expensive, least efficient and most impactful part of the supply chain.”5

Typical urban parcel delivery trucks have an outsize impact:

“Claudia Adriazola-Steil, acting director of the Urban Mobility Program at the World Resources Institute’s Ross Center for Sustainable Cities, said freight represented 15 percent of the vehicles on the roads in urban areas, but occupied 40 percent of the space. ‘They also emit 50 percent of greenhouse gas emissions and account for 25 percent of fatalities ….’”6

Since vehicle speeds in downtown areas are typically slow, most parcels are not very heavy, and the ability to travel in lanes narrower than a typical truck is a great advantage, a substantial portion of this last-mile delivery can be done by cargo bikes.

Both Fed-Ex and UPS are now building out electric-assist cargo bike fleets in many Western European cities. UPS has also announced plans to test electric-assist cycles in Manhattan.7

How much of the last-mile delivery business can be filled by cargo bikes? A report by the Rapid Transition Alliance says that “In London, it’s estimated that up to 14% of small van journeys in the most congested parts of the city could be made with cargo bikes.”8 City Changer Cargo Bike estimates that in Europe “up to 50% of urban delivery and service trips could be replaced by cargo bikes….”9

It’s important to note that big corporations aren’t the only, or even the major, players in this movement. Small businesses of every sort – ice-cream vendors, bakeries, self-employed carpenters and plumbers, corner grocery stores – are also turning to cargo bikes. The City Changer Cargo Bike report says that “It is important to highlight that the jobs created by cargo bikes are mainly created by Small and Medium-size Enterprises.”10

For small companies or large, the low cost of cargo bikes compared to delivery vans is a compelling factor. The New York Times cites estimates that “financial benefits to businesses range from 70-90% cost savings compared to reliance on delivery vans.”11

The cost savings come not only from the low initial purchase price and low operating costs of cargo bikes, but also from the fact that “electric cargo bikes delivered goods 60 percent faster than vans did in urban centers, and that an electric cargo bike dropped off 10 parcels an hour compared with a van’s six.”12

It’s no wonder the cargo bike industry is experiencing rapid growth. Kevin Mayne of Cycling Industries Europe says sales are growing at 60% per year across the European Union and could reach 2 million cargo bike sales per year by 2030.

Delivery vans in European cities are typically powered by diesel. Replacing a few hundred thousand diesel delivery vans with e-cargo bikes will obviously have a significant positive impact on both urban air quality and carbon emissions.

But what if diesel delivery vans are switched instead to similar-sized electric delivery vans? Does that make the urban delivery business environmentally benign?

Far from it. Electric delivery vans are just as heavy as their diesel counterparts. That means they cause just as much wear and tear on city streets, they pose just as much collision danger to cyclists, pedestrians, and people in smaller vehicles, and they produce just as much toxic tire and brake dust.

Finally, there is the significant impact of mining and manufacturing all that vehicle weight, in terms of upfront carbon emissions and many other environmental ills. There are environmental costs in manufacturing cargo bikes too, of course. But whereas a delivery van represents a large amount of weight for a much smaller delivery payload, a cargo bike is a small amount of weight for a relatively large payload.

In a listing by Merchants Fleet of the “5 Best Electric Cargo Vans for Professionals”, all the vehicles have an empty-weight a good bit higher than the maximum weight of cargo they can carry. (The ratios of empty vehicle weight to maximum cargo weight range from about 1.5 to 3.5.)13

By contrast, a recent list of recommended electric-assist cargo bikes shows that the ratios are flipped: all of these vehicles can carry a lot more cargo than the vehicles themselves weigh, with most in the 4 – 5 times cargo-weight-to-empty-vehicle-weight range.14

One other factor is particularly worthy of note. The lithium which is a key ingredient of current electric-vehicle batteries is difficult, perhaps impossible, to mine and refine in an environmentally benign way. Lithium batteries will be in extremely high demand if we are to “electrify everything” while also ramping up storage of renewably, intermittently generated electricity. Given these constraints, shouldn’t we take care to use lithium batteries in the most efficient ways?

Let’s look at two contrasting examples. An Urban Arrow Cargo bike has a load capacity of 249 kg (550 lbs), and a battery weight of 2.6 kg (5.7 lbs)15 – a payload-to-battery-weight ratio of about 44.

The Arrival H3L3 electric van has a load capacity of 1484 kg (3272 lbs) and its battery is rated at 111 kWh.16 If we assume, generously, that the Arrival’s battery weighs roughly the same as Tesla’s 100 kWh battery, then the battery weight is 625 kg (1377 lbs).17 The Arrival then has a payload-to-battery-weight ratio of about 2.4.

In this set of examples, the e-cargo bike has a payload-to-battery-weight ratio almost 20 times as high as the ratio for the e-cargo van.

Clearly, this ratio is just one of many factors to consider. The typical e-cargo van can carry far heavier loads, at much higher speeds, and with a longer range between charges, than e-cargo bike can manage. But for millions of urban last-mile deliveries, these theoretical advantages of e-cargo vans are of little or no practical value. In congested urban areas where travel speeds are low, daily routes are short, and for deliveries in the 1 – 200 kg weight range, the e-cargo bike can be a perfectly adequate device with a small fraction of the financial and environmental costs of e-cargo vans.

On Dundas Street, Toronto, 2018.

Cargo bikes, or just bikes that carry cargo?

A rapid rollout of cargo bikes in relatively dense urban areas is an obvious step towards sustainability. But should you buy a cargo bike for personal use?

Probably not, in my opinion – though there will be many exceptions. Here is why I think cargo bikes are overkill for an average person.

Most importantly, the bikes most of us have been familiar with for decades are already a very good device for carrying small amounts of cargo, particularly with simple add-ons such as a rack and/or front baskets.

A speed fetish was long promoted by many bike retailers, according to which a “real bike” was as light as possible and was ridden by a MAMIL – Middle-Aged Male In Lycra – who carried nothing heavier than a credit car. Cargo bikes can represent a chance for retailers to swing the pendulum to the opposite extreme, promoting the new category as a necessity for anyone who might want to carry more than a loaf of bread.

In spite of bike-industry biases, countless people have always used their bikes – any bikes – in routine shopping tasks. And with the addition of a sturdy cargo rack and a set of saddlebags, aka panniers, a standard-form bike can easily carry 25 kg or more of groceries. Or hardware, or gardening supplies, or a laptop computer and set of office clothes, or a stack of university textbooks.

The bikes now designed and marketed as cargo bikes can typically carry several times as much weight, to be sure. But how often do you need that capability, and is it worth the considerable downside that comes with cargo bikes?

Cargo bikes are typically a good bit longer and a lot heavier than standard-model bikes. That makes them more complicated to store. You probably won’t be able to carry a big cargo bike up stairs to an apartment, and you might not sleep well if you have to leave an expensive cargo bike locked on the street.

If you only occasionally need to carry larger amounts of cargo, you’re likely to get tired of riding a needlessly heavy and bulky bike the rest of the time.

If you occasionally carry your bike on a bus, train, or on a rack behind a car, a long cargo bike may be difficult or impossible to transport the same way.

Depending on the form factor, you may find a cargo bike doesn’t handle well in spite of its large weight capacity. Long-tail cargo bikes, with an extra-long rack over the rear wheel, can carry a lot of weight when that weight is distributed evenly on both sides of the rack. But if the load is a single heavy object, you may find it difficult to strap the load on the top of the rear rack so that it doesn’t topple bike and rider to one side or the other. (As one who has tried to load a big reclining chair onto a rear rack and ride down the road, I can attest that it’s harder than it sounds.)

Long-tail cargo bike. Photo by Richard Masoner on flickr.com, licensed via Creative Commons 2.0.

 

Box-style cargo bike in Lublin, Poland. Photo by Porozumienie Rowerowe, “Community cargo rental”, via Wikimedia Commons.

The large box style cargo bikes known as bakfiets solve those balance problems, but are typically heavy, long, and thus difficult to store. They can be ideal for moving around a city with children, though many parents will not feel comfortable doing so unless there is a great network of safe streets and protected bike lanes.

For people who have a secure storage space such as a garage, and the budget to own more than one bike, and for whom it will often be helpful to be able to carry loads of 100 kg or more by bike – a cargo bike might be a great buy. Or, perhaps a cargo trailer will be more practical, since it can add great cargo-carrying ability to an ordinary bike on an as-needed basis.18

Ideally, though, every urban area will soon have a good range of cargo-bike businesses, and some of those businesses will rent or loan cargo bikes to the rest of us who just occasionally need that extra capacity.

• • •

In the next installment of this series on transportation, we’ll look at a sector in which no significant device-level fixes are on the horizon.

References

1 See A Visual History of the Cargo Bike, from Mechanic Cycling, Haverford, Pennsylvania.

2 For an overview of a wide range of new cargo bikes and urban delivery initiatives, see the annual magazine of the International Cargo Bike Festival.

3 In North America wattage restrictions vary but many jurisdictions allow e-assist bikes with motors up to 750 Watt output.

4 Stakeholder’s Guide: Expanding the reach of cargo bikes in Europe, published by CycleLogistics and City Changer Cargo Bike, 2022.

5 “A Bicycle Built for Transporting Cargo Takes Off,” by Tanya Mohn, New York Times, June 29, 2022.

6 Tanya Mohn, New York Times, June 29, 2022.

7 Tanya Mohn, New York Times, June 29, 2022.

8 Large-tired and tested: how Europe’s cargo bike roll-out is delivering, 18 August 2021.

9 Stakeholder’s Guide: Expanding the reach of cargo bikes in Europe, 2022.

10 Stakeholder’s Guide: Expanding the reach of cargo bikes in Europe, 2022.

11 Tanya Mohn, New York Times, June 29, 2022.

12 Tanya Mohn, New York Times, June 29, 2022.

13 “5 Best Electric Cargo Vans for Professionals”, Merchants Fleet.

14 “10 Best Electric Cargo Bikes for Families and Businesses in 2022,” BikeExchange, Sept 1, 2022.

15 “10 Best Electric Cargo Bikes for Families and Businesses in 2022,” BikeExchange, Sept 1, 2022.

16 5 Best Electric Cargo Vans for Professionals”, Merchants Fleet.

17 “How much do Tesla’s batteries weigh?”, The Motor Digest, Nov 27, 2021.

18 One example is the Bikes At Work lineup. I have used their 96” long trailer for about 15 years to haul lumber, slabs of granite, voluminous bags of compost and many other loads that would have been awkward or impossible to move with most cargo bikes.

Photo at top of page: “Eco-friendly delivery with DHL in London: a quadracycle in action,” by Deutsche Post DHL on flickr.com, Creative Commons 2.0 license.

All the king’s horses

ALSO PUBLISHED ON RESILIENCE

When was the last time one of your relatives bought so many victuals they needed a team of a hundred horses to haul the load back from the market?

Perhaps it was that time your great uncle Napoleon was preparing for his not-so-great trip to Moscow.

Or perhaps your great great great uncle Christopher needed a long team of horses to move his groceries before he got in a boat to try to sail to India. Or your extra-extra-great grandpa Richard I, who really bought in bulk before his trip to the Holy Land in 1191.

More likely, though, if you live in North America, somebody from your family needed a team of hundreds of horses to bring home groceries in the past 24 hours – even if they were only picking up a carton of milk or a bag of cheese puffs.

“Need” might not be exactly the right word – but they used a team of hundreds of horses nonetheless, in the sense that they fired up the same hundreds-of-horsepower engine that they use for nearly every local trip no matter how light the cargo.

This grotesque mismatch between the task at hand and the tools we use for that task, have played a large role in pushing us deep into a climate crisis. At the same time, this mismatch can point us to one of the easiest, least painful ways we can move toward true sustainability.

When we look at our dominant car culture, we can consider it from a system standpoint or a device standpoint. On a system level, we have constructed a society in which homes are far from schools, from workplaces, from stores and from entertainment. We have built wide roads and streets that facilitate, at least potentially, high speeds between these newly distant sites. We have devoted most urban public space to huge heavy vehicles that make roads and streets unsafe for pedestrians and cyclists. It took decades to build this environmental nightmare and it will take decades to fix it, even if we run out of cheap energy somewhere close to the beginning of the process.

The previous installment in this series looked at transportation on a systems level, with a call to change lifestyles so that we don’t need to, and we don’t imagine we need to, travel many thousands of kilometres every year. This post takes a narrower focus.

Strictly at the device level, some of the vehicles we use are reasonably appropriate for their typical usage, while many others are beyond absurd.

At the beginning of the 1970s, my summer job was working on a highway construction crew. As an impressionable teenager I was suitably awed when an older man, who worked as a dump-truck driver, showed me his new sports car and told me how powerful its engine was.

I don’t remember the number of horsepower it boasted, but I do remember my Dad’s reaction.

“That is really ridiculous!” my dad exclaimed. “The engine in his car is just as powerful as the engines in all of our gravel trucks!”

My dad was no opponent of car culture – he had a successful career building highways throughout half a dozen US states. But after growing up on a Minnesota farm, driving tractors and grain trucks since before he was ten years old, he had an instinctive understanding of the capabilities and usefulness of different engines.

He understood that for steady work hauling 10 or 15 ton loads, often along hilly highways at speeds up to the speed limit, a 300-hp engine was appropriate. But for hauling one young man along roads with the same speed limits, a 300-hp engine was ludicrous.

As it was in the 1970s, so it is today. Some of the devices we use for transportation – those used to haul heavy freight – have a reasonably powered engine for their assigned task. It will be a difficult challenge to convert their engines from fossil fuels. (Simply moving a lot less freight in the first place is one answer, of course, but that’s a system-level topic beyond the scope of this essay.)

But a greater number of the vehicles on our roads have power systems vastly beyond those needed, even if we accept for the moment that the “need” is to carry a person tens of thousands of kilometres along roads every year, sometimes at speeds of roughly 100 km/hr. There would be no technical hurdles in accomplishing that same task with power systems using a small fraction of the energy. The challenge would be cultural, not technical.

Going nowhere fast. Newly manufactured light trucks awaiting distribution and sale, parked outside GM Canada building in Oshawa, Ontario, Aug 28 2022.

“Get just enough horsepower to do the job.”

That 1970s truck driver whose muscle car impressed the teenage me and perplexed my practical dad? It turns out that by driving a car with the power of a dump truck, he was an avatar of the American future. Today, it is commonplace for Americans to make their daily rounds in cars with the power of dump trucks.

And how much power is that? In 2010, Brian Lindgren, a marketing director for Kenworth Trucks, offered prospective truck buyers this advice:

“One of the big mistakes many people make with dump truck engines is they spec too much power, says Lindgren. ‘You should get just enough horsepower to do the job. Generally, 350 to 400 horsepower is plenty for most applications. Extra horsepower just uses more fuel, puts more strain on the rest of the drivetrain, and adds cost up front.’”1 

Other trucking-industry publications make similar points: an appropriate horsepower range is somewhere between 300 and 600 horsepower, with the high numbers corresponding to semi-trailer tractors and “Super Dump” trucks carrying highway-legal payloads up to 26 tons.2, 3

This is the kind of advice that makes sense to practical business people who want to earn a profit from their vehicle. For that purpose, there’s no point in forking out a lot of extra cash upfront, and extra cash at every fuel re-fill, for an engine with horsepower far in excess of what’s needed.

Those practical considerations don’t count for much with the typical North American car buyer. The typical cargo is small – just one, and occasionally two or three, warm bodies weighing from 150 – 300 pounds each. But apparently the weight of desire for status, and the weight of drivers’ insecurity, has been on a decades-long climb – at least if we go by the size and horsepower rating of the vehicles they choose to move around in.

This chart by Kevin Drum illustrates the trend: 

By Kevin Drum, from his article “Raw Data: Horsepower of New Vehicles in the US”, on Jabberwocking.

As recently as 1980, when most buyers of pick-up trucks had a day-to-day practical need for such a vehicle, engines were only slightly more powerful than the engines in typical cars. Today pick-up truck horsepower ratings have nearly tripled, while engines in cars have more than doubled.

What that graph doesn’t show is that pick-up trucks have become a far larger share of the automotive market in recent years, as if an epidemic of cattle-ranching or lumberjacking has taken hold in every North American suburb.

A question arises: are today’s four-door pick-up trucks merely oversize cars in disguise, or are today’s oversize SUVs actually trucks in disguise?

Whatever. The US Department of Energy lumps them together with other cars as “light-duty” vehicles, and finds that in this category:

“Preliminary data for model year 2021 show that the average horsepower (hp) reached 252, an increase of more than 6 hp over the 2020 model year.”4 

If the average new personal passenger vehicle has a 252 horsepower engine, then something like half of those vehicles have a good bit more power – right up into the dump-truck or semi-trailer tractor range.

Car & Driver reported in 2021 that “Finding an SUV with about 400 horsepower is relatively easy these days. That number just doesn’t impress like it once did.”

These days if your personal vehicle has only as much power as an ordinary dump truck, you’re not making much of a statement. But don’t worry – if you’ve got the cash or the credit, you can buy a vehicle with as much or more power as a big, big, big dump truck. Car & Driver lists 15 SUVs and crossover vehicles with power ratings from just under 600 hp to more than 700 hp.5 

Costs, benefits, and opportunities

What’s the problem, defenders of superpowered cars might ask? After all, just looking at horsepower is an oversimplification that might give the wrong impression. The horsepower rating of passenger vehicles nearly doubled in the period 1989 to 2019, and vehicle weight increased by 24%, but it’s not as if fuel economy has taken a big hit. In fact, average fuel economy improved modestly.

And one ultra-important measure of performance improved dramatically in spite of the extra weight: “acceleration increased (i.e., 0-60 mph times dropped) by 37%.”6  Car & Driver notes that the most powerful SUV on its list “can get to 60 mph in just 3.6 seconds.”7 

Just think of all the time that saves a rushed commuter! Between the time a driver leaves a red light and catches up to the snarl of traffic behind the next light, he might save two or three seconds. Between the time he turns onto a freeway on-ramp and the time he reaches the maximum speed that won’t risk an expensive speeding ticket, he might save several seconds, compared to driving with the woefully underpowered vehicles of the 1970s or 1980s. In a long commute with many starts and stops, those precious seconds saved through superior acceleration could add up to a minute or more.

And it’s not as if that massive engine is working hard and really sucking down fuel all the time. Once the vehicle is at cruising speed, power usage is way down and fuel usage is (relatively) lower too.

All true. And yet …. Manufacturing cars that weigh a lot more, and manufacturing millions of bigger engines to propel those heavier vehicles, also has a correspondingly larger carbon footprint. All cars – be they subcompacts or supersize SUVs, gas, diesel, or electric – have resulted in a lot of carbon emissions before the impatient driver even revs the engine for the first time. The more materials used to make that vehicle, the bigger the upfront carbon emissions.

If or when we switch to electric vehicles, those issues of weight and power don’t magically go away. The larger and heavier a vehicle is, the larger the battery needs to be. The larger the batteries, the more scarce minerals we need to mine and refine, and the more high-speed chargers we’ll need to get these big batteries recharged in a reasonable length of time.

We’re in a period when we have a desperate need to curtail fossil fuel combustion, but during which we have only a small fraction of the clean renewable energy installations that would be needed to power an industrial society like ours. It would be folly to continue building bulky, heavy, massively overpowered vehicles to move one or two passengers along roads, and therefore devoting a huge share of our still scarce clean power supplies to building and/or operating that oversized vehicle fleet.

On a system level this is a long-term and complicated problem; we need to dramatically reduce the need to travel far and fast just to get to work or school on a daily basis. But on a device level it is simple. We could build cars that carry one or two people8 , and occasionally the smaller families that are typical today, plus a typical haul of groceries, at speeds up to but not a lot faster than highway speed limits. We could employ the latest automotive engineering improvements, not to move ever heavier vehicles ever faster, but to power lighter vehicles with the best energy efficiency currently achievable.

As we try to “electrify everything”, with clean renewable energy installations that are still nowhere near adequate for the transition, we should ensure that cars and “light trucks” make the smallest possible demands on our electricity network.

Technically that’s easy but culturally it’s hard. We have an auto industry, after all, whose key to bigger profits has been to persuade people their cars are never big enough or powerful enough. And we have millions of traffic-bound motorists convinced that it really matters whether their cars can go from 0 – 60 in 10 seconds or 5 seconds.

• • •

In the next installment in this series, we’ll look at a combined system-and-device level problem. In the cities where most people live, a big share of vehicle trips don’t actually require use of a car or a truck. How can we change the mode share of urban trips quickly, using existing technologies, and what kind of devices are most appropriate?

Illustration at top of post: detail from Market Economy, composed by author from Creative Commons-licensed images – Horses from image at pxhere.com; wagon and driver from photo by Milo Bost0ck, from Wikimedia Commons; Wal-Mart Supercentre, N Lexington-Springmill Rd, Ontario, OH, photo by Kirk Allen, from Wikimedia Commons; milk carton illustration by Paul Robinson, from Wikimedia Commons; random number background created in Excel.

References

1 Source: constructionequipment.com.

2 “How much horsepower does a semi-truck have?” on Trucker’s Corner, August 6, 2019.

3 “Dump Trucks 101: how to choose the right one”, on customtruck.com

4 US Office of Energy Efficiency and Renewable Energy Fact of the Week, Feb 7, 2022.

5 Car & Driver, “Most Powerful Crossovers and SUVs on Sale Today,” Nov 13, 2021.

6 Personal Transportation Factsheet, University of Michigan.

7 Car & Driver, Nov 13, 2021.

8 “In 1977, the U.S. average vehicle occupancy was 1.87 persons per vehicle. In 2018, average car occupancy was 1.5 persons per vehicle.” – Personal Transportation Factsheet, University of Michigan.

Hypermobility hits the wall

Also published on Resilience

Imagine a luxurious civilization in which every person has a motorized travel allowance of 4000 kilometers every year, with unused amounts one year carried forward to allow more distant journeys, perhaps every few years. Imagine also that non-motorized travel is not tallied in this quota, so that a person who makes their daily rounds on foot or bicycle can use all or most of their motorized travel quota for those occasional longer journeys.

It’s true that a motorized travel quota of 4000 km per year would seem a mite restrictive to most people in wealthy industrial countries. But such a travel allowance would have been beyond the dreams of all of humanity up until the past two centuries. And such a travel allowance would also mean a significant increase in mobility for a large share of the global population today.

Still, as long as we “electrify everything” why should we even think about reducing the amount of travel?

Australian scholar Patrick Moriarty floats the idea of a motorized travel allowance of 4000 km per year1, based on a recognition that the environmental harms of high-speed and motorized mobility go far beyond the climate-destabilizing emissions that come from internal combustion cars, trucks, trains, planes and ships.

In several articles and a recent book2 Moriarty and his frequent co-author Damon Honnery provide perspective on what Moriarty refers to as “hypermobility”. The number of passenger kilometers per person per year exploded by a factor of 240 between 1900 and 2018.3

“This overall 240-fold rise is extraordinary, considering the less than five-fold global population increase over the same period. It is even about 30 times the growth in real global GDP.”4

The global average for motorized travel is now about 6,300 km per person per year. At the extremes, however, US residents average over 30,000 km per person per year, while in some countries the average is only a few hundred km per person per year.5

Could the high degree of mobility now standard in the US be extended to the whole world’s population? Not likely. Moriarty calculates that if each person in the world were to travel 30,000 km per year in motorized transport, “world transport energy levels alone would be about 668 EJ, greater than global total commercial energy use of 576 EJ for 2018.”6

Increasing mobility services for the world’s poorest people, while decreasing motorized mobility for the wealthiest, is not only an environmental necessity, it is also a matter of equity. As part of examining those issues, we need to ask this simple question: what good is transportation?

We’re moving, but are we getting anywhere?

Moriarty calls attention to an issue that is so basic it is often overlooked: “What people really want is not mobility itself, but access—to workplaces, schools, shops, friends and family, entertainment etc.”7

Sometimes more mobility also means more access – for example, a person acquires a car, and that means many more workplaces, schools, and shopping opportunities are within a practical daily travel distance. But other times more mobility results in little or no gain in access. As two-car households became the norm in many rural areas, grocery stores and even schools consolidated in bigger towns, so that a car trip became necessary for access to things that used to be a walkable distance away in each small town.

Sometimes more mobility for some people means less accessibility for others. When expressways cut through urban neighbourhoods, lower-income residents of those areas may face long hikes across noisy and polluted overpasses just to get to school or a store.8

In the sprawling suburbs of North American cities, people typically drive much farther to get to work every day than their parents or grandparents did 25 or 50 years ago. But to what end? If you can now travel 50, or 70, or 100 km/hr on your commute, but the drive still takes an hour because you go so much farther, what have you gained?

Moriarty asks us to consider to what extent the explosion in mobility – hypermobility – has actually improved the quality of life even for those privileged enough to participate:

“Personal travel levels in wealthy OECD countries are several times higher than in 1950, yet people then did not regard themselves as ‘travel deprived’.”9

While the benefits of hypermobility are unclear, the costs are crushing and unsustainable.

Death rides along

Motorized transportation always comes with environmental costs. These costs are especially high when each individual travels in their own motorized carriage. Only a fraction of these environmental costs go away when a car or truck fueled by internal combustion is traded for an equivalent vehicle powered by electricity.

Many researchers have cited the high upfront carbon emissions involved in building a car or truck. Before the vehicle is delivered to a customer, a lot of carbon dioxide has been emitted in the mining and refining of the ores, the transportation of materials and parts, and the assembly. For currently produced electric cars and trucks, the upfront carbon emissions are typically even higher than the upfront emissions from an equivalent combustion vehicle. It will be a long time, if ever, before that manufacturing and transport chain runs on clean energy sources. In the meantime every new electric car signifies a big burst of carbon already emitted to the atmosphere.

If only the damage stopped there. But building and maintaining roads, bridges and parking lots is also a carbon-emissions intensive activity, with additional negative impacts on biodiversity and watershed drainage.  And though an electric vehicle has no tailpipe emissions, that doesn’t mean that electric driving is pollution-free:

“[N]on-exhaust emissions of fine particular matter from tire wear is actually greater than for equivalent conventional vehicles, because EVs are heavier than their conventionally fueled counterparts.”10

Finally, there is the direct toll from the inevitable, predictable “accidents” that occur when multi-tonne objects hurtle along roads at high speeds:

“In 2018, some 1.35 million people were killed on the world’s roads, with millions more injured, many seriously. Paradoxically, most of the casualties occur in low vehicle ownership countries, and are pedestrians and cyclists, not vehicle occupants.”11

Death reliably accompanies high-speed transportation – but the fatalities disproportionately accrue to those not privileged enough to travel.

Slowing the machine

To recap the argument: the mass production of high-speed vehicles has made possible an explosion in mobility for a privileged portion of the global population. But the energy costs of transportation increase exponentially, not linearly, with increases in speed.  Hypermobility was fueled overwhelmingly by fossil fuels, and even if we could recreate the infrastructure of hypermobility using renewable energies, the transition period would result in a burst of upfront carbon emissions which our ecosystem can ill afford. Finally, if we concentrate on ramping up renewable technologies to serve the rapacious energy demands of hypermobility, it will be more difficult and will take longer to convert all other essential energy services – for producing and distributing foods, for heating and cooling of buildings, and for distributing clean drinking water, to name a few examples – so that they can run off the same renewable electricity sources.

It is clearly possible for a society to prosper with a lot less motorized travel than our hypermobile society now regards as normal. Given the manifold environmental costs and manifest social inequality of a hypermobile society, we need to rapidly cut down not only on the use of fossil fuel in transportation, but also the total amount of motorized transportation as measured in passenger-kilometers (p-k) per person per year. This is the underpinning for Moriarty’s “tentative proposal for an average aspirational target of 4000 vehicular p-k per person per year.”12

But how to begin applying the brakes?

In an article titled “Reducing Personal Mobility for Climate Change Mitigation”, Moriarty and Honnery have examined the likely impacts of various factors on overall motorized mobility. Neither new information technology services, carpooling, or land-use planning changes are likely to result in significant reductions in travel, particularly not in the 10 – 25 year time frame that is so critical for staving off a truly catastrophic climate crisis. Large and rapid increases in the market price of fossil fuels, on the other hand, would dramatically hurt lower-income people while allowing high-income people – who consume by far the most energy per capita – to maintain their current personal habits. Thus Moriarty and Honnery conclude:

“The only equitable approach is to reduce the convenience of car travel, for example, by large travel speed reductions and by a reversal of the usual present ranking of travel modes: car, public transport, and active modes.” [emphasis mine]13

Expressed graphically, that reversal of priorities would look like this chart from Mikael Colville-Andersen’s book Copenhagenize:

From Copenhagenize, by Mikael Colville-Andersen, Island Press, 2018; reviewed here.

At the outset of the motor age, walking and cycling routes were as direct and convenient as possible. As streets were dedicated to fast, dangerous cars, walking and cycling routes started to zigzag through many detours, or they simply disappeared, while priority was given to auto routes.

To make our cities safer and healthier, while also reducing the voracious energy demands of motorized transport, we need to flip the hierarchy once more, putting active transportation first, public transit second, and cars third. That way we can improve access to essential services even as motorized mobility drops.

Within cities where most people live, I think Moriarty and Honnery are right that this change would result in a substantial reduction in overall motorized kilometers per capita, and would do so in a generally equitable manner.

Easier said than done, of course. While many European cities have made major strides in this regard, even timid moves to de-privilege cars are tough for city councils to enact in North America.

A personal travel allotment of 4,000 km per year will seem outrageously low to most North Americans, and it is hard to imagine any North American politician – at least anyone with a hope of ever being elected – saying a good word about the idea.

Yet the luxury of any high-speed travel at all is a recent phenomenon, and there is no reason to take for granted that this extravagance will last very long. We do know that we need drastic, rapid change in our energy consumption patterns if we are to avoid civilization-threatening environmental instability.

We might not find it within ourselves to voluntarily steer away from our high-speed, hypermobile way of life. But if, a few decades from now, our society is in free-fall due to rapid-fire environmental disasters, the complex infrastructure needed for widespread motorized transport may be but a faint memory.

* * *

Though I only came across Moriarty’s work a few years ago, for most of my adult life I unwittingly lived within a motorized travel allotment of 4,000 km/yr – with one major exception. More than 40 years ago, as a new resident of an urban metropolis, I realized it was a bizarre waste of horsepower to use a car simply to haul my (then) scrawny carcass along city streets. Besides, I found it healthier, cheaper, more interesting, and definitely more fun to ride a bike to work, to concerts, to stores, and nearly everywhere else I wanted to go. I was fortunate, too, to be able to choose a home close to my workplace, or change my workplace to be closer to my preferred home; throughout several decades I never needed to regularly commute by car.

But: I did get on a plane once or twice a year, and sometimes several times a year. For many years these air journeys accounted for most of my motorized transport kilometers. Later I learned that of all typical modern travel modes, air travel was the most environmentally damaging and the least sustainable.

In upcoming installments in this series I’ll look at the energy needs, both real and imagined, for personal transportation within cities; and at the impact of hyper-hypermobility as embodied in routine air travel.

Illustration at top of page courtesy of pxhere.com, free for personal and commercial use under CC0 public domain license.

References

1 See his brief article in Academia Letters, “A proposal for limits on vehicular passenger travel levels”, published in September 2021.

2 Patrick Moriarty and Damon Honnery, Switching Off: Meeting Our Energy Needs in a Constrained Future, Springer, 2022.

3 P. Moriarty, “Global Passenger Transport,” MDPI Encyclopedia, February 2021.

4 P. Moriarty, Academia Letters, “A proposal for limits on vehicular passenger travel levels”.

5 P. Moriarty, “Global Passenger Transport”.

6 P. Moriarty, “Global Passenger Transport”.

7 P. Moriarty, “A proposal for limits on vehicular passenger travel levels”.

8 For more on the trade-offs between mobility and accessibility see my article “The Mobility Maze”.

9 P. Moriarty, “A proposal for limits on vehicular passenger travel levels”.

10 P. Moriarty, “Global Passenger Transport”.

11 P. Moriarty, “A proposal for limits on vehicular passenger travel levels”.

12 P. Moriarty, “A proposal for limits on vehicular passenger travel levels”.

13 Patrick Moriarty and Damon Honnery, “Reducing Personal Mobility for Climate Change Mitigation”, in Handbook of Climate Change Mitigation and Adaptation, Springer, 2022, pages 2501 – 2534.

 

Essential services

Also published on Resilience

When you live in a petrostate like Canada or the US, and someone publicly floats the idea that we should begin to limit fossil fuel use by stopping a specific pipeline or levying a small carbon tax, you can expect someone to respond with the statement “Well, we can’t quit fossil fuels overnight.”

This statement is delivered with an air of argument-ending authority, as if the insight is worthy of simultaneous Nobel Prizes in physics, economics, accounting and rocket science.

Now, I’ve never heard anybody seriously suggest that we can quit fossil fuels overnight. It has also occurred to me that “we can’t quit fossil fuels overnight” may be a stand-in for “we really don’t want to, and we have no intention of, even slightly slowing down fossil fuel use, not anytime soon!”

But let’s put cynicism aside, and let “we can’t quit fossil fuels overnight” serve not as the end of a discussion, but as the beginning.

Why can’t we quit fossil fuels tomorrow, and what implications does that have for our way of life given that we are already in a climate emergency?

For the foreseeable future we will need aviation fuel for the water bombers that fight forest fires, which we can expect to occur with increasing frequency and intensity. We will need fuel for helicopters that rescue people from severe flooding, also increasing in frequency. As droughts become more frequent and widespread, with resulting crop failures, we will need fossil fuels to ship emergency food supplies long distances.

For the near-term future we will need diesel fuel for the tractors that power the industrial food system1, and more diesel fuel to transport the food to all the far-away megacities.2

For at least a decade or a few, we will need fossil fuels to run the mines and factories that can produce equipment for concentrating, transmitting, storing, and utilizing renewable-energies.3

On the other hand, purely from a climate-stabilizing point of view, we should quit fossil fuels tomorrow. Our fossil fuel consumption has already resulted in dangerous levels of atmospheric carbon dioxide and other greenhouse gases, and every additional increment of these gases will make our current climate crisis worse.

This is quite the predicament. If we do quit fossil fuels overnight, huge numbers of people will starve, the global economy will crash, and civilization will most likely collapse. If we don’t quit fossil fuels overnight, or at least damn soon, climate catastrophes will rapidly grow both in frequency and intensity, and yes, huge numbers of people will starve, the global economy will crash, and civilization will most likely collapse.

The best outcome seems clear to me (though not to most policymakers): we must decide which fossil-fueled services are essential to keeping us alive and helping us through our predicament, and we must drastically curtail all other fossil-fueled services, starting immediately.

As we quickly learned to do during the covid pandemic, we must distinguish between essential activities and discretionary activities. We must then recognize that where discretionary activities result in greenhouse gas emissions we can no longer afford them. We must come to this recognition and course of action not for a year or two of a pandemic, however, but for a generation or two, perhaps a lifetime or two, perhaps a century or two, until the climate crisis is in the rear-view mirror.

Sounds drastic. Sounds like what we might do if, when we say we’re in a climate crisis, we actually mean it – if we mean that our situation demands a crisis response, instead of continued wishful thinking the crisis will go away without any drastic measures.

Clearly the biggest changes would need to come from those of us in the “developed” world, those of us whose lifestyles contribute by far the biggest share of greenhouse gas emissions. For a large share of the world’s population, a drastic curtailment of discretionary fossil-fueled services would entail little change in behaviour, given that they consume little fossil fuel for either essential or discretionary services.

What might a distinction between essential and discretionary use of fossil fuels mean in practice? Regarding aviation, for example, we might recognize use of water bombers in fighting forest fires, helicopters in performing rescues, and airlifts to deliver essential food and medical supplies in the aftermaths of hurricanes. Fossil-powered vacations – flights to beach holidays, golf outings, or “eco-tourism” adventures that start and end on a runway – are clearly discretionary and would be banned or severely restricted, if we were to take the climate crisis seriously.

Use of fossil-powered industry for the manufacture of renewal energy equipment or basic medical technology would be deemed essential. Fossil-fueled manufacture of leaf blowers, recreational vehicles, patio heaters, and most of the products that litter our big-box stores before littering our garages and then our landfills, would be recognized as discretionary and would cease.

Production of plastic packaging and containers for some specialized needs might be essential while we develop and ramp up the production of replacements. Production of single-use disposables, most plastic packaging, and plastic toys would be deemed discretionary and would cease.

Production and use of fossil-burning trucks to haul heavy but essential goods long distances would be deemed essential, until renewable-energy powered trucks can be built in sufficient numbers and until our logistics systems can be right-sized. Production and much use of passenger-vehicles, especially the huge, heavy, monstrously over-powered passenger vehicles like SUVs and “light trucks”, would be deemed discretionary and drastically scaled back, in number and in size, starting now.

These few examples just scratch the surface, of course, and distinguishing between “essential” and “discretionary” will be more difficult in some cases than in others. Achieving political momentum for the necessary changes may be especially difficult. Individual, voluntary actions – important in acting as signposts and building credibility – will accomplish little on their own unless accompanied by society-wide transformation.4

Much of the change can and must happen in our transportation practices and systems, and that will be the subject of the several upcoming installments in this series.

In North America, and wherever high-energy-consumptive lifestyles are dominant, there is such vast wastage of fossil energy that we can make a big difference in emissions in a hurry – if we choose to. Though we can quibble for decades about the final difficult steps in getting to a zero carbon emissions economy, in the immediate future there is an awful lot of low-hanging fruit.

What matters now is not what we promise for 2050 – it’s what we actually do in 2023, 2024 and 2025 to get us on course.

 

Notes

1Jason Bradford provides an excellent overview of why it will be particularly challenging to transform our industrial agricultural system to renewable energy. His work looks at the limitations inherent in running large tractors on battery power, and the need for a significantly larger share of the population living and working in agricultural areas in future. These changes, clearly, cannot and will not happen overnight. See Bradford’s report The Future is Rural: Food System Adaptations to the Great Simplification (2019), and his chapter “The Future is Rural: Societal Adaptation to Energy Descent”, in Energy Transition and Economic Sufficiency (2021).

2Alice Friedemann’s 2016 book When Trucks Stop Running: Energy and the Future of Transportation is a good overview of the challenges in running heavy freight-moving trucks or trains on battery power.

3Even if and when we have developed a huge capacity in renewable-electricity generation, many industrial processes, particularly those which require high-temperature and high heat flux, will be difficult or impossible to convert from fossil fuel combustion to electricity. This includes production of concrete, steel, and a large array of chemicals used in industrial products. For an overview with further references, see my chapter “Energy Sprawl in the Renewable-Energy Sector”, in Energy Transition and Economic Sufficiency (2021).

4Finding the right mix of governmental policies that can quickly end the discretionary consumption of fossil fuels is not in the scope of this series. Such policies must not only be effective and practicable, but equitable. For one such mechanism, see Stan Cox’s excellent work on fair-share energy rations in Beyond the Green New Deal: Ending the Climate Emergency While We Still Can (2020).

 

Image at top of page: accessed from Pixabay, free for commercial and non-commercial use.

“Getting to zero” is a lousy goal

Also published on Resilience

In an alternate reality, gradually moving toward a zero-carbon-emission economy and arriving there in two or three decades would be a laudable accomplishment.

In an alternate reality –   for example, the reality that might result from turning the clock back to 1975 – a twenty-five year process of eliminating all anthropogenic greenhouse gas emissions could avert a climate crisis.

But in our reality in 2022, with far too much carbon dioxide already flowing through the atmosphere and the climate crisis worsening every year, knowingly emitting more greenhouse gases for another two decades is a shockingly cavalier dance with destruction.

This understanding of the climate crisis guides the work of Bruce King and Chris Magwood. Their own field of construction, they write, can, and indeed must, become a net storer of carbon – and not by 2050 by rather by the early 2030’s.

Their new book Build Beyond Zero (Island Press, June 2022) puts the focus on so-called “embodied emissions”, also known more clearly as “upfront emissions”. The construction industry accounts for up to 15 percent of global warming emissions, and most of the emissions occur during manufacturing of building materials.

No matter how parsimonious new buildings might be with energy during their operating lifetimes, an upfront burst of carbon emissions has global warming impact when we can least afford it: right away. “A ton of emissions released today,” write King and Magwood, “has far more climate impact than a ton of emissions released a decade from now.”

Emissions released today, they emphasize, push us immediately closer to climate crisis tipping points, and emissions released today will continue to heat the globe throughout the life of a building.

Their goal, then, is to push the construction industry as a whole to grapple with the crucial issue of upfront emissions. The construction industry can, they believe, rapidly transform into a very significant net sequesterer of carbon emissions.

 That goal is expressed in their “15 x 50” graph.

By 2050, Bruce King and Chris Magwood say, the construction industry can and should sequester a net 15 gigatonnes of carbon dioxide annually. Graphic from Build Beyond Zero, Island Press, 2022, page 238.

A wide range of building materials are now or can become net storers of carbon – and those that can’t must be rapidly phased out of production or minimized.

The bulk of Build Beyond Zero consists of careful examination of major categories of building materials, plus consideration of different stages including construction, demolition, or disassembly and re-use.

Concrete – by far the largest category of building material by weight and by current emissions –is a major focus of research. King and Magwood outline many methods that are already available to reduce the carbon intensity of concrete production, as well as potential methods that could allow the net storage of carbon within concrete.

Equally important, though, are construction materials that can reduce and in some cases eliminate the use of concrete – for example, adobe and rammed earth walls and floors.

By far the largest share of carbon sequestration in buildings could come from biogenic sources ranging from timber to straw to new materials produced by fungal mycelia or algae.

Harvesting homes

“Tall timber” is a popular buzzphrase for building methods that can sequester carbon within building structures, but King and Magwood are more excited about much smaller plant materials such as wheat straw or rice hulls. Their discussion of the pros and cons of increased use of wood products is enlightening.

“Assessing the degree of carbon storage offered by timber products is not at all straightforward. Far from being the poster child for carbon-storing building, the use of timber in buildings requires a very nuanced understanding of supply chain issues and forest-level carbon stocks in order to be certain we’re not doing harm in the process of trying to do good.” (Build Beyond Zero, page 111)

First, when trees are cut down typically only half of the above-ground biomass makes it into building products; the rest decomposes and otherwise emits its stored carbon back into the atmosphere. Second, particularly where a large stand of trees is clear-cut and the ground is exposed to the elements, much of the below-ground stored carbon also returns to the atmosphere. Third, even once a replacement stand of trees has grown up, a monoculture stand seldom stores as much carbon as the original forest did, and the monoculture is also a big loss for biodiversity.

To the extent that we do harvest trees for construction, then, “We need to take responsibility for ensuring that we are growing forests at a rate that far exceeds our removals from them. Notice that we are talking about growing forests and not just planting trees.” (page 115)

This careful nuance is not always evident in their discussion of agricultural residues, in my opinion. The “15 X 50” goal includes the conversion of huge quantities of so-called “residues” – wheat straw, rice hulls, and sunflower stalk pith, to give a few examples – into long-lasting building materials. But what effects would this have on the long-term health of agricultural soils, if most of these so-called residues are routinely removed from the agricultural cycle rather than being returned to the soil? What level of such total-plant harvesting is truly sustainable?

Yet there is obvious appeal in the use of more fast-growing small plants as building material. Straw can sequester about twice as much carbon per hectare per year as forests do, while “the carbon sequestration and storage efficiency of hemp biomass is an order of magnitude higher than that of trees or straw.” (page 99)

There are many existing methods to turn small plants into building materials, ranging from structural supports to insulation to long-lasting, non-toxic finishes. It is reasonable to hope for the creation of many more such building materials, if industry can develop new carbon-emissions-free adhesives to help shape fibers and particles into a myriad of shapes. King and Magwood note that existing industrial practices are likely to act as hurdles in this quest:

“Nature provides plenty of examples and clues for making nontoxic bioadhesives in species such as mussels and spiders. However, the introduction and scaling of these potentially game-changing materials is so far hampered in the same way as bioplastics: by an extremely risk-averse construction industry and by a petrochemical industry keen to keep and expand market share ….” (page 162) 

Straw-bale construction project in Australia, 2012. Photo by Brett and Sue Coulstock, accessed via Flickr under Creative Commons license.

We don’t have 30 more years

Build Beyond Zero is a comprehensive and clear overview of construction practices and their potential climate impact in the near future. It does not, however, provide any “how-to” lessons for would-be builders or renovators to use in their own projects. For that purpose, both King and Magwood have already published extensively in books such as Essential Hempcrete Construction: The Complete Step-by-Step Guide; Essential Prefab Straw Bale Construction: The Complete Step-by-Step Guide; and Buildings of Earth and Straw: Structural Design for Rammed Earth and Straw Bale Architecture.

In Build Beyond Zero, King and Magwood offer an essential manifesto for anyone involved in commissioning or carrying out construction or renovation, anyone involved in the production of building materials, anyone involved in the establishment or modification of building codes, anyone involved in construction education.

It’s time for everyone involved with construction to become climate-literate, and to realize that upfront carbon emissions from buildings are as important if not more important than operating emissions during the buildings’ lifetimes. It’s time to realize that construction, perhaps more than most industries, has the capability of going beyond zero to become a significant net storer of carbon.

That opportunity represents an urgent task:

“It has taken more than 30 years for energy efficiency to approach a central role in building sector education …. We can’t wait that long to teach people how to make carbon-storing buildings. If we follow the usual path, the climate will be long past repair by the time enough designers and builders have learned how to fix it.” (page 173)

With global greenhouse gases already at catastrophic levels, we have dug ourselves into a deep hole and it’s nowhere near enough to gradually slow down and then stop digging deeper – we also need to fill that hole, ASAP.

As Build Beyond Zero puts it, “‘Getting to zero,” to repeat one more time, is a lousy goal, or anyway incomplete. You make a mess, you clean it up, as my mother would say. You don’t just stop messing, you also start cleaning.”

Photo at top of page: Limestone quarry and cement kiln, Bowmanville Ontario, winter 2016.