Modular Nuclear Power
Nukes have long been the third rail to the environmental movement; Greenpeace, after all, got its start as an anti-nuke organization. But while radioactive waste and the risk of major accidents still leave many greens wary of nuclear power, there's no ignoring the fact that nuclear is the only utility-scale, non-intermittent electricity source that doesn't emit carbon. If you replaced all of the U.S.'s nuclear plants — which supply about a fifth of the the nation's electricity — with coal plants, carbon emissions would skyrocket.
But there's still a reluctance to build nuclear plants — no new one has been constructed in the U.S. in decades — and it goes beyond environmental concerns. Nuclear power plants are incredibly expensive investments, and right now few utilities would take on the financial risk of building one, or get banks to lend them the necessary capital, even with additional government aid. But what if you could shrink the size of a nuclear plant? That's what companies like NuScale Power and Babcock & Wilcox are trying to do. By building a modular plant that might be a quarter the size of a the current multi-gigawatt operations, it's possible to reduce the capital expenditures needed to start construction and cut the risk that would be associated with an accident. We may at last be approaching a time that nuclear goes nimble.