The world has a problem with overheating. And the problem is going to last at least 10,000 years per a study published in Nature. In the near term, we have to take bold steps to move the needle on climate change.
But what bold steps will have the biggest impact and the lowest cost? While the world’s economy is far from a zero-sum game, it’s not infinite either, so we should prioritize expenditures in the near term.
At the highest level, the options are:
- Avoid — Shift to low- or no-carbon approaches.
- Remove — Take carbon from the atmosphere and put it somewhere.
- Adapt — Deal with the various consequences.
The lens for this assessment is the long-term impact of money spent in the short term. Among other things, this means that the assessment isn’t concerned with end game of any particular strategy, but the reality of the next 5 to 10 years.
Let’s tease each of the three categories apart a bit.
This set of approaches looks at the primary sources of climate change and attempts to eliminate CO2e emissions. The big three sources of emissions are generation, transportation, and infrastructure, especially buildings by most accountings.
For generation, the approaches are clear today. Investing in wind and solar generation is the most obvious path forward. Grid studies show that every MWh of wind and solar generation eliminates almost exactly a MWh of fossil fuel generation. Every MWh of fossil fuel generation emits between 500 kg and 1,100 kg of CO2, along with other pollutants. Wind and solar generation can be built at very large scale in 5 years because manufacturing, distribution, and construction are easily done in numerous parallel streams and the industries are globally distributed supply chains today. The more rapidly wind and solar are built, the less CO2 is emitted. And wind and solar are already the cheapest forms of new utility-scale generation in dozens of countries globally. Starting today, it’s possible to consume most investment budgets solely with wind and solar in the next 5 years and have working carbon avoidance in place in that time frame.
The secondary and less intuitive generation solution is to spread fracking technology wide and far, build natural gas generation, and shut down coal plants. While natural gas generation still emits CO2, it’s typically around 500 kg of CO2 per MWh, while even the best of supercritical coal plants are at 750 kg and most are around a metric ton. Every MWh of gas generation, if it displaces a MWh of coal generation, is a net benefit. The question, though, and it’s a difficult one, is how little gas generation can we build and how fast can we shut it down?
An additional proviso related to gas generation is that it has been the fracked gas which has reduced the price of gas-generated electricity, which has led to many nuclear plants in the developed world no longer being economically viable. While new nuclear is not at all competitive with wind and solar, shutting down existing nuclear prematurely typically increases CO2 emissions, which is contraindicated. We can see that playing out in multiple US states at present. Subsidizing existing nuclear plants to stay working until end of life is a relative no-brainer.
For transportation, the paths are clear as well. Battery-electric ground transportation is the primary path of the future. Electric cars in some cases already have a lower total cost of ownership than equivalent internal combustion cars without incentives, and by 2018–2022, depending on the study, will all have a lower total cost of ownership (TCO). Electric full-sized, long-range buses are now on the market, have been deployed in the hundreds of thousands on roads in China, and are quickly increasing in numbers in other markets. Electric pickup trucks are appearing, and Tesla’s is eagerly awaited. Tesla’s freight truck line is expected to be announced shortly and is already affecting the stock prices of competing truck companies. Large-scale manufacturers of electric urban vehicles such as garbage trucks are gaining market share globally as well. This transition is underway. Oddly, an investment vehicle that appears not to exist is an electrification index fund which has Tesla, BYD, major battery players, and the like.
For other forms of transportation such as air, rail, ocean, and freight trains, which typically rely on aviation fuels and diesel, there are existing solutions as well. For regional commuter planes, several major manufacturers have battery-electric planes in planning — which, given the value of lower noise, will be more valuable for multiple reasons. For aviation fuel, there are multiple approved low-carbon alternatives. For diesel, there are multiple alternatives, including biodiesel and artificial diesel. However, unlike battery-electric road vehicles, the price differential is higher and not reversing. Low-carbon aviation fuels were approved in 2011 and tested, but no carrier is using them regularly due to cost. This requires policy movements, specifically pricing of carbon emissions or emissions regulations. This is happening in fits and starts with a much greater likelihood of occurring in Europe, China, India, and Canada than in the USA over the next 5 years (given the current political climate — although, the bi-partisan climate solutions caucus is a hopeful sign).
For infrastructure and buildings, there’s a very difficult chicken-and-egg problem. Studies have shown that making buildings more efficient has not resulted in significant reductions in overall emissions in many cases. Part of this is due to the embodied CO2 in the building materials, which — with extraction, refinement, distribution, and construction — are not sources of sequestration today regardless of material. But a larger part is source energy. As long as fossil fuels are used to generate energy for heating, cooling, ventilation, and lighting, the buildings are going to be CO2 emitters.
The solutions for built infrastructure are less clear based on the past 30 years, but there are emerging solutions. Shifting to carbon-sequestering concrete such as Calera’s reduces significantly the CO2 burden of built infrastructure. Wood-frame construction has a lower carbon footprint than brick construction.
However, the single largest thing that can be done to reduce carbon footprints of built infrastructure is to shift all energy inputs to low- to no-carbon inputs all the way along the value chain. That means wind and solar generation and electric vehicles will go a long way to eliminating embodied carbon, and electric heating and cooling via wind and solar will eliminate CO2 emissions during operation. Building efficiency is then solely a cost factor, not an emissions factor.
The answers are not nearly as good in this space as in the avoidance space. There are three elements to removal, each of which has their own challenges: capture, distribution, and sequestration. As a data point on the challenges, Australia has spent a billion dollars on at-source sequestration approaches over 19 years and has sequestered a minuscule amount of CO2 at a cost of about $4,300 per ton.
Capture breaks down into two categories and various technologies, none of which are nearly as compelling as advocates assert.
- Air carbon capture: This has technical solutions and biological solutions. It’s primarily constrained by the 410 ppm of CO2 in the atmosphere, requiring enormous volumes of air to move past capture approaches.
- At source capture: This approach attempts to capture CO2 emissions as they are created at generation plants. This approach is constrained by sheer economic non-viability.
Distribution is problematic as well, but especially for the at-source capture approach. CO2 emitted is 2–3 times the mass of the fuel fed into generators due to oxygen from the atmosphere binding with carbon in the fuel. That means that supply chains which are optimized to bring large volumes of fuel to generators must be re-optimized to carry much larger volumes of lower-value CO2 away from the sites. Distribution has a carbon-footprint, so until distribution fully electrifies, net emissions are problematic.
Sequestration has its own set of problems. The primary consumer of CO2 industrially is enhanced oil recovery. This process uses CO2 as a solvent to liquefy left-behind tarry crude oil in played out fields and allow it to be pumped out. About 70% of the CO2 used remains sequestered, but the oil that’s pumped out has more CO2 embodied. It’s not a virtuous cycle. The scale of the problem is enormous as well. In 2008, enhanced oil recovery consumed CO2 equivalent to the emissions of 13 of the 500 coal plants in the USA.
Air carbon capture, whether technical or biological, reduces the distribution and sequestration problems to greater and lesser extents. Both approaches attempt to capture carbon at the place where it will be used by industrial or biological processes, eliminating distribution problems and one portion of the sequestration problem in that they turn the CO2 into plant mass or durable goods. But neither come close to dealing with the scale problem. The most promising biological approach might address 12% of annual emissions before tapping out, but long-term sequestration to actually reduce CO2 in the carbon cycle would take centuries. In other words, biological approaches have some potential to scale, but little potential to reduce challenges in the next two centuries.
As such, I couldn’t recommend significant removal investments in the next 5 years. It will become more and more important, as long term studies that model the next 10,000 years instead of the next 90 show slowly increasing warming even after we stop emitting for most of those 10,000 years and very large sea level rises. But solving the emissions problem is this century’s work.
The fundamental problem with adaptation is, adaptation to what? Global warming and climate change are causing ecosystems problems, climate refugee situations, sea level rise challenges, coral bleaching, wildfire increases, drought increases, flooding increases, and agricultural shifts and reductions. Each of those has its own adaptation set. But most places on earth will be subject to a set of challenges.
Let’s just take the case of drought and pull on that string. Syrian drought was made worse by climate change. The drought caused challenges with reduction in arable land due to irrigation shortages. This led to grazing vs cropping farmer conflicts. This led to farm failures and flight to cities. This led to economic setbacks. This led to greater conflict and a citizenry under a dictator more ripe for revolt. This led to a civil war. This led to massive refugee flight to neighbouring countries and into Europe especially. This was part of the rise of populist isolationism which was a force in the recent US election.
Let’s take another case. Miami is attempting to adapt to sea level rise to protect its very pricey real estate. But it’s built on spongy limestone and it’s flat with 5.5 million residents living lower than 6′ above sea level. Adaptation to preserve Miami is hideously expensive, with $300 million futile pumps currently deployed, but that’s money that is being spent today that is thrown away in 20–30 years as the sea level increases accelerate. Can you make money on helping Miami adapt in the short term? Yes. Is it a high-impact world-saver? No, by definition it is solely local to Miami, which is doomed as a city, and to South Florida, which will see the salinization of the Biscayne Aquifer by 2050.
Adaptation of agriculture is equally problematic. One major study concluded that due to shifts in growing seasons and available water, currently two-crop-per-season agricultural regions would become one-crop-per-season regions, significantly decreasing output. This is an adaptation, and a necessary one, but it’s a negative adaptation. Many adaptations require money to change without commensurate increases in productivity and economic output.
One further example. A town in Louisiana on an island with a long causeway at sea level has been dwindling for 20 years. It had 300 homes. Now it has under 30 occupied homes. It’s going to cost close to $50 million to move those remaining families. Where exactly is the value proposition for spending money in this situation, or the Alaskan city which is facing eradication due to climate change destabilizing river banks with 70 meter annual erosion. This is just forced, expensive change.
There are places where adaptation will make sense. New York City is one such example. It’s insanely economically productive and wealthy. They can afford to build up sea defences of various types to enable them to be more resilient in the face of Superstorm Sandy situations. They can afford to clean up when those fail. They can afford to hold back the rising seas. It’s possible that the Pearl River Delta is another place like that. Vancouver, BC, can easily afford the $50 million necessary to put a flood barrage under the Burrard Street Bridge to preserve the expensive False Creek real estate.
But these are specific and narrow adaptations, not broadly impactful ones. Yes, they will be useful in some places, but they mostly aren’t necessary in the next 5 to 10 years and will not do anything about the actual problem, just put bandages on expensive flesh.
Of the three major areas of potential investment, it appears clear that the place to spend the lion’s share of money in the next few years is in avoiding the problem. We have the solutions. We just have to build them en masse quickly.