Startups, universities, and major companies are vying to commercialize a nuclear fusion reactor.
5 Big Ideas for Making Fusion Power a Reality
by Tom Clynes | IEEE Spectrum
The joke has been around almost as long as the dream: Nuclear fusion energy is 30 years away … and always will be. But now, more than 80 years after Australian physicist Mark Oliphant first observed deuterium atoms fusing and releasing dollops of energy, it may finally be time to update the punch line.
Over the past several years, more than two dozen research groups — impressively staffed and well-funded startups, university programs, and corporate projects — have achieved eye-opening advances in controlled nuclear fusion. They’re building fusion reactors based on radically different designs that challenge the two mainstream approaches, which use either a huge, doughnut-shaped magnetic vessel called a tokamak or enormously powerful lasers.
What’s more, some of these groups are predicting significant fusion milestones within the next five years, including reaching the breakeven point at which the energy produced surpasses the energy used to spark the reaction. That’s shockingly soon, considering that the mainstream projects pursuing the conventional tokamak and laser-based approaches have been laboring for decades and spent billions of dollars without achieving breakeven.
In Cambridge, Mass., MIT-affiliated researchers at Commonwealth Fusion Systems say their latest reactor design is on track to exceed breakeven by 2025. In the United Kingdom, a University of Oxford spin-off called First Light Fusion claims it will demonstrate breakeven in 2024. And in Southern California, the startup TAE Technologies has issued a breathtakingly ambitious five-year timeline for commercialization of its fusion reactor.
Irrational exuberance? Maybe. Fusion research is among the most costly of endeavors, depending on high inflows of cash just to pay a lab’s electricity bills. In the pursuit of funding, the temptation to overstate future achievements is strong. And past expectations of impending breakthroughs have repeatedly been dashed. What’s changed now is that advances in high-speed computing, materials science, and modeling and simulation are helping to topple once-recalcitrant technical hurdles, and significant amounts of money are flowing into the field.
Some of the new fusion projects are putting the newest generation of supercomputers to work to better understand and tweak the behavior of the ultrahigh-temperature plasma in which hydrogen nuclei fuse to form helium. Others have reopened promising lines of inquiry that were shelved decades ago. Still others are exploiting new superconductors or hybridizing the mainstream concepts.
Despite their powerful tools and creative approaches, many of these new ventures will fail. But if just one succeeds in building a reactor capable of producing electricity economically, it could fundamentally transform the course of human civilization. In a fusion reaction, a single gram of the hydrogen isotopes that are most commonly used could theoretically yield the same energy as 11 metric tons of coal, with helium as the only lasting by-product.
As climate change accelerates and demand for electricity soars, nuclear fusion promises a zero-carbon, low-waste baseload source of power, one that is relatively clean and comes with no risk of meltdowns or weaponization. This tantalizing possibility has kept the fusion dream alive for decades. Could one of these scrappy startups finally succeed in making fusion a practical reality?