Returning to a subject I touched on a week or so ago, I thought it might be interesting to explain why I believe what I believe. To recap, I believe that the only strategies that make any sense for reducing the amount of carbon we’re putting into the atmosphere are increased use of nuclear power and various engineering approaches for actively removing carbon from the atmosphere. Or, said another way, that the only way that conservation strategies or subsidies for alternative fuels make any sense are as ways of moving the Overton Window, i.e. setting the stage for other future strategies.
Let’s assume that everything that the global warming folks are saying is absolutely true. I recognize that a lot of people are hanging their hats on wondering whether global warming is actually happening, what role human action has on that, etc. I don’t want to talk about it at all. Just assume that global warming is happening and that we need to do something about it.
What’s the scope of the task? Well, according to the IEA in order to constrain the increase in temperature to 2°C we need to leave between 60% and 80% of proved fossil fuel reserves in the ground by 2050. Replacing that with other carbon-based fuel sources, e.g. biomass, doesn’t help. While constraining our use of fossil fuels we’ve got to rely on wind, solar, geothermal, and nuclear. Let’s also assume the larger, 80% figure.
The proved world fossil fuel reserves amount to about 22 quintillion BTUs. 20% of that (the most we can consume and meet the goal) is 4.4 quintillion BTUs. Divide that by 40 (the number of years over which we’ll be limiting our consumption in round numbers) gives us 110 quadrillion BTUs per year in consumption. Total world energy consumption is estimated at around 500 quadrillion BTUs per year and rising and most of that is in the form of fossil fuels, coal being the heavyweight champ. Nuclear provides a significant fraction. Wind, solar, geothermal and other low or no-carbon sources are tiny fractions of the whole.
Obviously, we can’t meet that goal by conservation alone. Over the last ten years Germany has only reduced its energy consumption by about 10%.
What would we need to do to reduce our consumption of fossil fuels to the target level? First, all of the countries in the world would need to participate including China and India. Otherwise anything we do will merely subsidize China and India’s consumption and they will just consume more.
Second, we’d need to stop selling and buying anything but hybrid or electric vehicles at all (hybrids actually appear to be stingier than EVs in terms of carbon production but that’s another subject). That really wouldn’t do much, at least not immediately. It would still take decades to reduce the number of gas-guzzling cars and trucks in the entire world fleet to the point at which we’ve really accomplished much (and remember: every year that goes by without actually reducing carbon production means we’d need to reduce carbon production by that much more in future years).
Third, we’d need to impose a carbon tax to incentivize conservation and the transition to new power sources and other transportation alternatives.
Fourth, we’d need to stop building coal-fired electrical power generation plants and phase out the use of the existing plants. As this article points out, the only real practical solution available now to satisfy those energy demands (also remember: all of those EVs will need more electricity than we can presently produce or transmit) is nuclear. The main barriers to bulding more nuclear power plants, at least here in the U. S., are regulatory and legal. There would need to be streamlined approval of new technologies, building sites, and reduced litigation. Even then the time constraints would present formidable problems.
In summary, that means that we’d need to do several things, none of which have proven politically possible to date, we’d need to do them immediately, we’d need to do all of them at once, and even if we did all of that it wouldn’t accomplish the objective.
The key resources required for all of this are money, time, and ingenuity. Under the circumstances all of those are limited. The question comes down to how much money are we willing to spend and how much time and effort are we willing to waste pursuing solutions that won’t work?
I think a better way of putting this is: if the climate scientists are right, we are screwed.
I favor conservation, but the reality is that it’s just not going to approach the magnitude required, for the reasons you list. I favor an expansion of nuclear, but making it happen politically is not really any more realistic than making something like a carbon tax happen – and it also wouldn’t do anything about the developing world. And the length of time to build and start up new plants severely limits the impact, even if we could all agree to start expanding nuclear today.
As for geoengineering, I think you’re right that it may end up being the only option. But it’s hardly a great one, and could easily backfire.
So, best to hope they’re wrong. I suspect most of your other readers are more optimistic than I am on that front.
I think there’s a sort of game theoretic way of looking at this. I gain practically nothing from the strategies that are being advocated. I’ll be dead before the target date. I don’t have any children. Reduced economic activity doesn’t help me a bit.
Increased economic activity does. The strategies that increase economic activity are the ones that should be advocated. The administration’s claims in that direction, all of the “green jobs”, are just vaporizing. Talk about excessive carbon emissions.
Are there enough accessible uranium reserves on the planet to build all the needed nuclear plants?
There are estimated to be more than 5 million tons of uranium and another 2 million tons of thorium. That’s more than enough. By many orders of magnitude. The core size of a good-sized nuclear reactor is something like 100,000 kg. or roughly 20 tons.