Texas-based startup Quidnet Energy just completed a test showing it can store energy for up to six months by pumping water underground. Using water to store electricity is hardly a new concept—pumped hydropower storage has been around for over a century. But the company hopes its twist on the technology could help bring cheap, long-duration energy storage to new places. —Casey CrownhartWhat you may have missed about Trump’s AI Action PlanThe executive orders and announcements coming from the White House since Donald Trump returned to office have painted an ambitious vision for America’s AI future, but the details have been sparse. The White House’s AI Action Plan, released last week, is meant to fix that.