The scientists from Institute for Solar Energy at the Polytechnic University and the Institute of Catalysis of the Spanish Higher Scientific Research Council in Madrid, Spain developped new solar cells that are more efficient.
The new material developed can supposedly absorb both visible and infrared light, giving it a theoretical absorption limit of 63 percent. The scientists added vanadium and titanium to a semiconductor, perhaps silicon, to alter the chemical properties and be able to create the intermediate level needed to attain a higher efficiency. You see, unlike in conventional solar cells wherein photons carrying energy from the sun excites electrons to a higher energy level (to create electricity), stepping-stone solar cells have an intermediate energy level where low-energy photons sit until another comes along to push it to a higher energy level.
This technology is not new. Back in 1997 by Spanish scientists there was a group from the Lawrence Berkeley National Laboratory in California made the very first cells based on the technology with a theoretical absorption limit of 57 percent.
Well, I hope that those solar cells gona reach the public very soon…. -:)