It has long been the Holy Grail of environmental scientists, but researchers at the Massachusetts Institute of Technology (MIT) are confident they have found an inexpensive way of producing hydrogen from water, paving the way for the widespread adoption of zero carbon fuel cells capable of powering buildings and cars.

The technique is similar to the way photosynthesis works in plants and is based on a new catalyst that can split water at room temperature to create hydrogen and oxygen.

The catalyst consists of cobalt metal, phosphate and an electrode that is placed into water. When electricity runs through the electrode, the cobalt and phosphate form a thin film on the electrode, and oxygen gas is produced. Another catalyst, such as platinum, can then be added to produce hydrogen gas from the water.

James Barber, Ernst Chain Professor of Biochemistry at Imperial College London, hailed the discovery as a huge breakthrough in the fight to reduce carbon emissions. "This is a major discovery with enormous implications for the future prosperity of humankind," he said. "The importance cannot be overstated since it opens up the door for developing new technologies for energy production thus reducing our dependence for fossil fuels and addressing the global climate change problem."

The process has many potential applications, but researchers Daniel Nocera and Matthew Kanan are convinced that its primary use will be to improve the reliability of solar energy systems.

Nocera said that power from photovoltaic cells generated during the day could be used to feed the catalyst water and create hydrogen and oxygen. This could then be combined at night to provide power for a building the recharging of an electric car.

"This is the nirvana of what we've been talking about for years," he said. " Solar power has always been a limited, far-off solution. Now we can seriously think about solar power."

The researchers admitted that further work needs to be done to integrate the technology with solar panels and increase the amount of electrical current the catalyst can handle. However, Nocera said he hoped that homeowners could be using the technology to run their homes from entirely clean energy within 10 years, with solar panels providing power during the day and a household fuel cell generating electricity throughout the night.