ENERGY SECURITYIf the Price Is Right: Fusion's Future in the U.S. Could Come Down to Dollars and Cents

By Colton Poore

Published 20 March 2023

Fusion energy is often hailed as a limitless source of clean energy, but new research suggests that may only be true if the price is right. The researchers say that the engineering challenges of fusion energy are only part of the problem — the other part lies in economics.

Fusion energy is often hailed as a limitless source of clean energy, but new research from Princeton University suggests that may only be true if the price is right.

In a study led by fusion expert Egemen Kolemen, associate professor of mechanical and aerospace engineering and the Andlinger Center for Energy and the Environment, and energy systems expert Jesse Jenkins, assistant professor of mechanical and aerospace engineering and the Andlinger Center for Energy and the Environment, Princeton researchers modeled the cost targets that a fusion reactor might have to meet to gain traction in a future U.S. energy grid.

The findings, published in Joule on Mar. 16, illustrated that the engineering challenges of fusion energy are only part of the problem — the other part lies in economics.

“People will not pay an unlimited amount of money for fusion energy if they could spend that money to generate clean energy more cost-effectively,” said Jacob Schwartz, a former postdoc with Kolemen and Jenkins who led the modeling for the study and currently works as a research physicist at the U.S. Department of Energy’s Princeton Plasma Physics Laboratory, a national laboratory working to advance the science of fusion energy. “Above a certain cost, even if we can engineer them, not many developers will want to build them.”

The model results demonstrated that the niche for fusion in the U.S. depends not only on the price of building a reactor but hinges greatly on the energy mix of the future grid and the cost of competing technologies like nuclear fission.

If the market for fusion is favorable, then even with capital costs as high as around $7000 per kilowatt, fusion could still reach 100 GW capacity — about the current capacity of U.S. nuclear power plants, which supply about a fifth of today’s electricity needs. But supposing alternative technologies like nuclear fission, hydrogen, carbon capture and storage, or long-duration battery storage successfully take root, capital costs might have to be less than half that price for fusion to reach the same 100 GW capacity.