A solar technology that uses water to produce fuel is being commercialised. Expect a prototype in 18 months.
The world’s first practical artificial leaf could soon be powering homes. This ‘leaf’, deveoped by Professor Daniel Nocera of the Masschusetts Institute of Technology, bears little resemblance to natural greenery, sharing only its function: photosynthesis, or the use of sunlight to convert carbon dioxide and water into oxygen and hydrogen.
Nocera has set up the company Sun Catalytix to commercialise the technology. The result, he hopes, will be a small power plant, the size of a refrigerator, capable of powering a home using only a bottle of water – which doesn’t even need to be clean. A prototype is expected within 18 months.
The technology was first developed by John Turner of the US National Renewable Energy Laboratory in Colorado, over a decade ago. But Nocera claims to have overcome the problems of cost and stability encountered by earlier versions, which relied on rare and expensive metals. In a presentation to the American Chemical Society, Nocera also claimed that his system can convert water into energy with ten times the efficiency of a natural leaf. And he’s confident he can improve on this.
So what does it look like, if not a leaf? It’s a floating silicon cell, about the size of an ultra-thin playing card, combining electronics and powerful – but, crucially, inexpensive – catalysts made from nickel and cobalt. When placed in water, it produces hydrogen and oxygen, which are syphoned off for use in a fuel cell. In the lab, it can do this for at least 45 hours without a drop in activity.
Out of the lab, Nocera says his leaf shows “particular promise” as a cheap source of electricity for domestic use in low-income countries. Placed in a single gallon of water in a bright sunlight, he claims the device could produce enough energy to supply a house in a developing country with electricity for a day.
Indian conglomerate Tata is the lead investor in an initial funding round worth $9.5 million. Other investors include the US firm Polaris Venture Partners. – Tom Young
Photo credit: prill/istock