With one bottle of drinking water and four hours of sunlight, MIT chemist Dan Nocera claims that he can produce 30 KWh of electricity, which is enough to power an entire household in the developing world. With about three gallons of river water, he could satisfy the daily energy needs of a large American home.

Using the electricity generated from a 30-square-meter photovoltaic array, Nocera’s cobalt-phosphate catalyst converts water and carbon dioxide into hydrogen and oxygen. The process is similar to organic photosynthesis, except that in nature, plants create energy in the form of sugars instead of hydrogen.

The hydrogen produced through artificial photosynthesis can be stored in a tank and later used to produce electricity by being recombined with oxygen in a fuel cell, even when the sun isn’t shining. Alternatively, the hydrogen can be converted into a liquid fuel.

With his start-up company, Sun Catalytix, which was awarded $4 million in government funding through the new ARPA-E agency, Nocera hopes to make the system affordable enough to allow individual homes to generate their own fuel and electricity on-site.