Chlorophyllictricty - green energy

[Reprinted from "New Zealand Education Review", vol. 12 no. 12]

Massey University researchers have developed a way of generating electricity using coloured dyes to create solar cells that they say could provide power at one tenth of the cost of current silicon-based solar technologies.

Pictured is Massey researcher Wayne Campbell with synthetic chlorophyll, one of the dyes used by the university's Nanomaterials Research Centre. Other dyes being tested are based on haemoglobin, the compound that gives blood its colour.

Campbell says that unlike the silicon-based solar cells currently on the market, the 10x10 cm green demonstration cells generate enough electricity to run a small fan in low-light conditions - making them ideal for cloudy climates. The dyes can also be incorporated into tinted windows that trap sunlight to generate electricity.

He says that the green solar cells are more environmentally friendly than silicon-based cells as they are made from titanium dioxide - a plentiful, renewable and non-toxic white mineral obtained from New Zealand's black sand.

"the refining of pure silicon, although a very abundant mineral, is energy-hungry and very expensive. And whereas silicon cells need direct sunlight to operate efficiently, these cells will work efficiently in low diffuse light conditions,: Campbell says.