“It’s not a question I get asked often,” said Michel Benderbauer, CEO of TAE Technologies, when asked about the economics of his company’s tokamak design. People are likely to be wondering how he plans to heat the plasma in his reactor to 1 billion degrees Celsius, compared to the 75 million the company has shown so far. But he says the questions overlap.
This extreme temperature is required because TAE uses boron as a fuel, along with hydrogen, which Binderbauer believes will eventually simplify the fusion reactor and result in a power plant that is cheaper to build. It puts costs somewhere between fission and renewable energy—about where Princeton designers say it should be. He points out that while fusion plants would be expensive to build, the fuel would be very cheap. In addition, the reduced risk of accidents and the reduction of high-level radioactive waste should mean a rollback of the expensive regulations that have driven up the costs of fission plants.
Bob Momgard, CEO of Commonwealth Fusion Systems, an MIT company, says he was happy to see the Princeton model, because he thinks the tokamak can smash those cost requirements. Essentially this claim lies in a very strong magnet that the company hopes will allow it to operate tokamak—and thus power plants—on a smaller scale, saving money. CFS is building a scaled-down fusion design prototype in Massachusetts that will include most of the components required for a working plant. “You can actually go and see it and touch it and look at the machines,” he says.
Nicholas Hooker, CEO of First Light Fusion, an inertial fusion company, published his economic analysis of fusion power in 2020 and was surprised to find that the biggest cost drivers were not in the fusion chamber and its unusual materials, but in the capacitors and turbines that any power plant needs.
However, Hooker expects to ramp up the work more slowly than some of his colleagues. “The first plants will stop all the time,” he says, and the industry will require significant government support — just like the solar industry has been over the past two decades. That’s why he thinks it’s a good thing that a lot of governments and companies are trying different approaches: It increases the chance that some technologies will survive.
Schwartz agrees. “It would be strange if the universe allowed only one form of fusion energy,” he says. This diversity is important, he says, because otherwise the industry risks discovering science only to prop itself up in an uneconomical corner. Nuclear fission and solar panels both went through similar periods of experimentation earlier in their technological paths. Over time, both have converged into individual designs—photovoltaics and the massive pressurized water reactors seen around the world—that have been built all over the world.
For fusion, however, first things first: science. It may not work anytime soon. It might take another 30 years. But Ward, though wary about the limits of grid fusion, still believes the research is really paying for itself, sparking new advances in basic science and in the creation of new materials. “I still think it was totally worth it,” he says.