Six percent improvement in conversion

Nov 2, 2007 15:54 GMT  ·  By

Solar cells use the light of the Sun to produce electric current, through an effect known as the photoelectric effect or the Hertz effect, due to its discovery by Heinrich Rudolf Hertz. It was first explained by Albert Einstein using the wave-particle duality of the light, work which gave Einstein the Nobel Prize for Physics (and not the Theory of Relativity as most people believe).

The wave-particle duality says that certain forms of energy can exist in a dual form at the same time, and addresses the inadequacy of classical concepts like "particle" and "wave" in fully describing the behavior of objects, various interpretations of the quantum mechanics theory trying to explain such a paradox.

Although a wave-particle duality is hard to explain, Einstein postulated that light is formed of small quanta called photons.

A solar cell is made generally of silicon-based chips. When exposed to light, the photoelectric effect takes place inside the chip. A quanta of energy, of e photon is absorbed by the atom, giving it enough energy for an electron to escape. An electron escaping from a silicon atom will positively charge the atom. Electric energy has been produced. By linking in series multiple solar cells, a higher electrical voltage can be obtained, and used to power certain electronic devices.

A newly produced organic material promises to convert 6 percent of the solar energy absorbed, meaning double the efficiency of the current silicon based solar cells. They are essentially plastic, can be cheaply manufactured and even be painted onto a surface.

The problem is that though the researches that manufactured the organic material claim the world record for the most efficient way of converting solar light into electricity, they have not yet allowed the evaluation from an independent team.

Keith Emery of the National Renewable Energy Laboratory in Golden, has looked through some of the reported data and found that it violates known physical laws, making the discovery claim invalid. The values that show extreme improvement might have been changed to influence how the program will be financed in the future.