Base Power has raised US$1 billion in a series C round led by Addition, with participation from a broad group of existing and new investors including Trust Ventures, Valor Equity Partners, Thrive Capital, Andreessen Horowitz, Ribbit, CapitalG, Lightspeed, Altimeter, StepStone, Elad Gil, 137 Ventures, Terrain, Waybury, Spark, BOND, Lowercarbon, Avenir, Glade Brook, Positive Sum, and 1789.