Climate Central: Solar energy is virtually limitless, generates no planet-warming greenhouse gases -- and is useless between sunset and sunrise. Wind energy is also plentiful and emits no carbon, and it can be harvested day or night, but not when the air is calm.
A discovery announced in Thursday's issue of Science may offer a way around these daunting problems, however. Chemists at the University of Calgary, in Canada, have found an efficient way to turn electricity from wind and solar energy into hydrogen, which...