- Charles Forsberg, Massachusetts Institute of Technology, Cambridge, Massachusetts
In a low-carbon world there is a need for energy storage to match nuclear, wind, and solar output with energy demand. Nuclear reactors produce heat and thus can couple to heat storage systems to provide dispatchable electricity while the reactor operates at full power. Heat storage enables nuclear reactors to replace fossil fuels as dispatchable energy sources and creates a parallel set of energy storage options to electricity (work) storage technologies (hydro pumped storage, batteries, etc.). The estimated costs of many heat storage technologies are more than a factor of ten less than electricity storage.
There are three categories of heat storage by functional capability and impacts on electricity markets. The first category includes six classes of heat storage technologies that couple to steam power cycles and may enable light water reactors to move electricity output from times of low electricity prices to times of high electricity prices. The second category includes Firebrick Resistance-Heated Energy Storage (FIRES) that converts low-price electricity into high-temperature stored heat for industry, transferring energy from the electrical to industrial sector at times of excess electricity and potentially setting a minimum electricity price slightly below that of fossil fuels. The third category are nuclear Brayton power cycles with FIRES and brick recuperators that enable high-temperature reactors to buy electricity when prices are low and sell electricity when prices are higher.