Fossil Fuels … Can’t Live with ’Em, Can We Live Without ‘Em?
The Future of Humanity, Part 2
This is Part 2 of my series on the future of humanity. Part 1 is here.
Where do we go from here?
As noted in Part 1 of this series, any transition from fossil fuels to renewable energy sources must deal with the fact that we cannot yet produce any of the four key foundational materials underlying our civilization — ammonia, steel, concrete, and plastics — without using fossil fuels to do so (source). This also means we cannot build the components of a new energy infrastructure — windmills, solar panels, batteries, electric vehicles, etc. — without relying on fossil fuels to manufacture them (source). So our path to a world run on renewable energy is necessarily paved with fossil fuels, at least in the near term.
Whether we leave gigatons of oil, gas, and coal in the ground or extract it and burn it all, within a few decades we will no longer have it at our disposal. The era of Big Oil is coming to an end. How is that process likely to play out?
We know how the Age of Oil will end
One of the biggest obstacles paralyzing global progress on climate change today is the fact that fossil fuel reserves still in the ground (that is, known deposits recoverable under current economic conditions) would, if captured and burned, release about 2,900 additional gigatons of CO2 into the atmosphere. But climate scientists estimate that to limit global warming to a 2° warmer future, we can only release about 1,100 gigatons of CO2 by 2050. Achieving that outcome would require leaving about a third of our oil reserves, half of our gas reserves, and over 80% of our coal reserves in the ground (source).
Can we muster the political will to do it? As we read the news every day, it is clear that political will is in pretty short supply. If anything, there is probably more political will — and certainly more political power and money — arrayed against leaving any of that oil in the ground than in favor of it. But there are also physical processes at work that are making those remaining fossil fuels both more difficult and more costly to extract.
Energy scientists tell us that our journey toward fossil fuel depletion will follow a predictable path, called the Hubbert Curve. In a nutshell, the Hubbert Curve states that the production rate for any finite resource — say, oil, natural gas, or coal — will follow a similar path, starting with a moderate flow, then increasing in rate until half the resource is extracted (for oil, that is the point dubbed “Peak Oil”), then production starts to fall in a symmetrical manner, at first gradually and then accelerating until the source is either depleted or abandoned due to extraction becoming too expensive.
A recent study by Laherrére and colleagues provides the best estimate to date as to how long it will take for this process to play out for different categories of “conventional” and “nonconventional” fossil fuels. Here is a summary of their conclusions:
- Conventional oil production peaked in 2005 and is now in decline.
- Nonconventional “fracked” oil will peak around 2025.
- Nonconventional tar sands and “heavy” Venezuelan oil will peak around 2030.
- Nonconventional “all liquids” fuel sources will peak around 2040.
Estimating these fossil fuel peaks and depletion timeframes is critical because any given energy source’s location on its Hubbert Curve has a big implications for its Energy Return on Energy Invested (EROEI, often shortened to EROI). This metric calculates the profitability of an energy source by dividing its energy output by its energy input; that is, the amount of energy it can produce, divided by the amount of energy needed to produce it. (source)
EROI relates to fossil fuel peaks and depletion rates because once an energy source reaches its peak, its EROI starts to decline (source). This is because energy extracted on the downside of the Hubbert Curve is harder to reach and lower in quality than the energy extracted on the upside of the curve. So it takes more energy input to produce the same energy output, lowering EROI as a result. Even though production might still be rising, the quality of the energy produced is lower, costs are higher, industry profits are shrinking, and the surplus available to support societal needs diminishes (see this article for an example of how this process has played out in Venezuela).
Eventually, the energy source becomes an unprofitable energy sink (more energy going in than coming out) and is abandoned. Note that this can happen long before the source is officially “empty”. As documented by Laherrére and colleagues, this is what is happening across the board for both conventional and nonconventional fossil fuel sources.
What these peaks, depletion rates, and EROI measures tell us is that these fuels are declining in accessibility, decreasing in quality, and increasing in cost. Yet, we will continue to burn them because we cannot power our current civilization, nor build a renewable energy infrastructure, without them. Crucially, we will continue to release dangerous amounts of CO2 and other pollutants into the atmosphere as we do so.
The world we’re making
Given the magnitude and complexity of the transition we must achieve, combined with a realistic assessment of our track record of delay, denial, and performative signaling so far, many climate scientists now believe a 2° warmer world is no longer a realistic hope or expectation. Even the United Nations, which reports annually on the progress countries are making on their net-zero carbon pledges, declared that if every country follows through with all pledges they have made, the expectation is still for a 2.7°C warmer world by 2100 (source).
Not by choice, but by delaying the costs of choosing, it looks like we are on our way to a 2–4°C warmer world.
Fossil fuels, which currently power 84% of modern civilization, will not “run out” or be abandoned anytime soon, certainly not in the timeframe climate scientists say they must in order to keep global warming below 2°C. We will continue pumping CO2 into the atmosphere because we must continue to burn fossil fuels as long as we have no other way to produce essential materials like ammonia, steel, concrete, and plastics. Nor can we build wind turbines, solar panels, high-capacity storage batteries, nor upgraded power grids.
The irony of our time is that we must continue to burn fossil fuels in order to build the renewable energy infrastructure we need to stop burning fossil fuels. As a consequence, it looks like global warming is not a problem the energy transition will solve. Rather, it appears to be a cost the energy transition will impose.
Human civilization can probably survive in a world without fossil fuels, but it will have to adapt to a significantly hotter, resource-depleted, and more dangerous planet to do so.
How hot will it get?
Climate scientists estimate future likely temperature ranges by quantifying the relationship between increases in CO2 in the atmosphere (in parts per million or ppm) and increases in Global Mean Temperature (GMT, in degrees centigrade). This relationship is complex because it is not linear; i.e., adding 50 ppm of CO2 increases GMT more when added to 280 ppm than when added to 400 ppm. A recent analysis of this relationship, based on multiple lines of evidence, suggests the following probabilities of additional heating when the level of CO2 doubles from 280 ppm (the pre-industrial average) to 560 ppm:
- a 66% probability that temperatures will rise between 2.6°C and 3.9°C
- a 95% probability that temperatures will rise between 2.3°C and 4.5°C
- a 5% probability that temperatures will rise between 2.0°C and 5.7°C
Today we are at 420 ppm and adding about 30 ppm per decade. At this rate, assuming fossil fuel shortages don’t stop us sooner, we can expect to reach 500 ppm and higher well before 2100, probably the lifetimes of many people alive today. Although there is a lot of uncertainty built into these numbers, one conclusion seems undeniable: any hope of keeping global temperatures below the Paris Agreement target of 1.5°C is a pipe dream. (source)
It’s going to get hotter. And it looks like it’s going to get hotter faster than most people expected it to.
