Utilities Eye Mini Nuclear Reactors as Climate Concerns Grow

U.S. utilities are looking to miniature nuclear reactors, as they seek a steady energy source that can help reduce the carbon emissions linked to climate change.

While power companies have stopped building big nuclear reactors because of cost overruns and construction delays, not all utilities are giving up on nuclear power.

Several U.S. utilities and power consortia—including Energy Northwest, Utah Associated Municipal Power Systems, and PacifiCorp, part of Warren Buffett’s Berkshire Hathaway Inc. —have entered into partnerships with manufacturers to build small modular reactors, or SMRs, attracted to their potential to produce carbon-free, 24-hour-a-day power.

Dozens of SMR developers world-wide—ranging from 22-person startup Oklo to Bill Gates-founded TerraPower—are testing designs for the reactors, which have less than a third of the generating capacity of traditional nukes and have components that can be mass-produced in factories.

Their development is backed by the U.S. Energy Department, which said last fall that it would invest $3.2 billion over seven years to support such projects to boost cleaner technologies and decarbonize the power sector.