If your car is a diesel, it will run. Liquid hydrogen, the fuel that powered the space shuttle’s main engines, could work, says Manuel Martinez-Sanchez, an aeronautics and astronautics professor at the Massachusetts Institute of Technology. But keeping hydrogen liquid requires maintaining it at a temperature below about –432°F. Storing it in a garage would be tricky, as would keeping it from freezing the engine.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.