Here's MIT's Technology Review:
Researchers have found a cheap and easy way to store the energy made by solar power
Researchers have made a major advance in inorganic chemistry that could lead to a cheap way to store energy from the sun. In so doing, they have solved one of the key problems in making solar energy a dominant source of electricity.
Daniel Nocera, a professor of chemistry at MIT, has developed a catalyst that can generate oxygen from a glass of water by splitting water molecules. The reaction frees hydrogen ions to make hydrogen gas. The catalyst, which is easy and cheap to make, could be used to generate vast amounts of hydrogen using sunlight to power the reactions. The hydrogen can then be burned or run through a fuel cell to generate electricity whenever it's needed, including when the sun isn't shining....MORE