This year there have been some major announcements regarding nuclear fusion. From the Lawrence Livermore Laboratory to a company based down the road from me in Cambridge, MA called Commonwealth Fusion Systems (CFS) it seems like we’re on the verge of some major advancements in this futuristic technology. The CEO of CFS is just the latest person to argue that fusion is an “essential” component of decarbonizing our world. I am in no way qualified to evaluate the technology being used here, or if the timelines presented by the various fusion backers are realistic, however even if they are correct (this is a big if), then that really doesn’t change the fundamental truth, that fusion probably won’t play a major role in decarbonizing our economy.
Let’s look at why. First, according to the timelines presented by the backers, we may have a working fusion reactor by 2025 and a commercial reactor by 2030. These targets seem pretty ambitious to me, considering we’ve been “10 years from fusion” since the 1960s, but for the sake of argument, let’s assume they are correct.
A working commercial fusion reactor would be an amazing achievement. It isn’t hard to imagine a future where fusion plays an important role in powering our society. Maybe fusion reactors will power our starships, or help us suck carbon out of the atmosphere.
But, they are unlikely to play a major role in decarbonizing our economy. If we have our first commercial fusion reactor by 2030, then that means we have managed to clear all the regulatory hurdles in at least one jurisdiction. But, that doesn’t mean every jurisdiction will automatically accept it. Creating regulations for a brand new type of power plant, particularly one with the word “nuclear” in it, would be challenging. Under normal circumstances, it would take years to get these regulations approved, and in the United States, much of this regulation is done by individual states. So we’re talking about potentially hundreds of individual jurisdictions who have to give their approval, and then each individual power plant has to win approval, potentially over the objections of local opposition. Siting new power plants is slow, combative, and bureaucratic.
Further, it takes years to build a new power plant. So if the first commercial plant is operational in 2030, how many others will be built that same year? One? Ten? How much power will these plants produce and at what cost? We have no idea what these costs would be, and it seems unlikely that the first iteration of a nuclear fusion plant would be the cheapest, and even if fusion is a wonderful technology, if it can’t compete with renewables on price, it isn’t going to get built (without subsidies).
That being said, even if we are able to build cheap, abundant nuclear fusion plants by the 2030s, and they are quickly approved by every major jurisdiction, we still have other problems.
Of the major sectors that require decarbonizing, the electrical grid is the easiest. Followed by light transportation and mass transit, and then building heat. Industry, heavy transportation, and agriculture are likely the hardest sectors to decarbonize. This is why the Biden climate plan focuses on decarbonizing the electricity, light transportation and building heat sectors between now and 2030, with research and development aimed at the other sectors in anticipation of decarbonization between 2030 and 2050.
Fusion reactors don’t create usable energy on their own. They create an enormous amount of heat that is used to boil water, which creates steam that is used to turn a turbine that generates electricity (all fossil fuel power plants follow the same principle).
As you can see, the timelines just don’t add up. If we decarbonize the electricity sector by 2030 or 2035, there won’t be much need for nuclear fusion. And if wind, solar, and storage have all become even cheaper than today, then fusion may not even compete on price and reliability.
Waiting for fusion reactors to become available before decarbonizing would be a disaster. At the current rate of emissions, we will use up our carbon budget in 10 years. If we wait that long to decarbonize, we will lock in 2 or 3 degrees C warming. 2 degrees would be extremely difficult, 3 degrees would be catastrophic.
However, in case you think I’m against fusion, let me be clear that I’m very much in favor of it. It’s an amazing technology that could play an important role in making our society truly sustainable. It’s possible (and perhaps likely) that there are ways fusion could help decarbonize our economy that I haven’t even thought of. And, having cheap, abundant, reliable, and pollution-free energy at our disposal is an unambiguously good development.
But, the danger is complacency. We cannot wait for some miraculous technology to save us. This isn’t an Ancient Greek play where the gods are going to swoop in at the last moment. We still don’t know if commercial fusion reactors are even viable, and we certainly don’t know if they will be available by 2030. We have solutions in hand that can help us cap and reduce our emissions immediately, and we need to implement them. Even if wind and solar are eventually supplanted by fusion reactors sometime in the future, we need to cut our emissions right away.
These advancements in fusion technology should be celebrated. These companies and labs should be funded, and we should encourage people to study the sciences and develop these and other sustainable technologies. But, we cannot put our faith in techno-wizardry with no guarantees of success. We simply don’t have time to wait for a miracle, especially when we can get moving in the right direction with the solutions we already have.
The Mangrove 