Solar cells could put power stations in space

Scientists at Rochester Institute of Technology in the US are developing the next generation of solar cells, advancing the technology that could put a solar power system into earth's orbit.

The US National Science Foundation recently awarded a three-year grant to Ryne Raffaelle and Thomas Gennett, co-directors of RIT's NanoPower Research Laboratory, to develop nanomaterials in support of NASA's space solar power program.

The notion of space solar power - discounted as farfetched and silly after the energy crunch of the 1970s - never completely went away. Some scientists and other visionaries remained intrigued by the idea of orbiting, football-field sized 'blankets' of solar cells that could generate tremendous amounts of power. NASA's program is revisiting the idea, pushing the latest technology as far as it will go.

Raffaelle and Gennett are working with other institutions to develop a solar cell that is light, thin and highly efficient. This solar cell, a thin-film device, will sandwich tiny granules of semi-conductor material, known as Quantum dots, and carbon nanotubes.

"In order to put football-field sized arrays in space, they need to be lightweight and flexible, and able to withstand the rigours of space," Raffaelle says. "Today's technology isn't good enough, but with the theoretical possibilities offered by nanomaterials it could become a reality."

Gennett adds: "The types of solar cells that we are working to develop are a clear departure from even the most advanced crystalline solar cells used in the space industry today. If we are successful it will result in a complete paradigm shift in space solar power generation."