MIT shines on solar panels

A new solar energy technique could apply to almost any window

Scientists at MIT have come up with a new method of generating solar power using windows to collect the Sun's rays.

The technique involves painting the glass or plastic in a window with a mixture of dies which absorb light of different wavelengths and direct it to the frame. Solar cells then collect the concentrated light.

Traditional solar cells have their light absorption boosted by tracking mirrors but these consume power and space, and are costly to maintain.

This new technique could apply to almost any window, and let skyscrapers, for example, generate large amounts of power to run internal systems.

"The project uses innovative design to achieve superior solar conversion without optical tracking," said Dr Aravinda Kini, programme manager in the Office of Basic Energy Sciences at the US Department of Energy, which sponsored the research.

"This accomplishment demonstrates the critical importance of innovative basic research in bringing about revolutionary advances in solar energy in a cost-effective manner."

The idea behind using glass to collect light in this way is not new, but previous attempts have failed because light dissipation weakens the efficiency of the solar cells.

The team used laser technology to alter the concentration of the dies to channel light more effectively.

"We made it so the light can travel a much longer distance," said Jon Mapel, graduate student in the Department of Electrical Engineering and Computer Science at MIT.

"We were able to substantially reduce light transport losses, resulting in a tenfold increase in the amount of power converted by the solar cells."