This story was originally published by the Guardian and is reproduced here as part of the Climate Desk collaboration. Deep in the confines of the hulking, brutalist headquarters of the US Department of Energy, down one of its long, starkly lit corridors, sits a small, unheralded office that is poised to play a pivotal role in America’s shift away from fossil fuels and help the world stave off disastrous global heating. The department’s loan programs office was “essentially dormant” under Donald Trump, according to its head, Jigar Shah, but has now come roaring back with a huge war chest to bankroll emerging clean energy projects and technology. Last year’s vast Inflation Reduction Act grew the previously moribund office’s loan authority to $140 billion, while adding a new program worth another $250 billion in loan guarantees to retool projects that help cut planet-heating emissions.