A scientist at the Massachusetts Institute of Technology in Cambridge, Mass. has made a breakthrough in artificial leaf technology that may lead to these leaves providing basic power to homes.

About the shape of a poker card but thinner, the device is fashioned from silicon, electronics and catalysts, substances that accelerate chemical reactions that otherwise would not occur, or would run slowly.

Placed in a single gallon of water in a bright sunlight, the device could produce enough electricity to supply a house in a developing country with electricity for a day.

The hydrogen and oxygen gases would be stored in a fuel cell, which uses those two materials to produce electricity, located either on top of the house or beside it.
The breakthrough was a discovery of cheaper and stable elements to make this process work longer and more efficiently. You can read the full story at http://www.dailymail.co.uk/sciencetech/article-1370839/Scientists-Holy-Grail-science-mastermind-worlds-artificial-leaf.html

I love reading these types of stories, gives me a sense of hope for the future