Nature's Dimmer Switch Could Be Key To Future Solar Panels

A new molecular mechanism identified in plants could aid the government in creating and using solar energy to lower costs and improve energy resources in remote locations.

Researchers from Lawrence Berkeley National Laboratory have discovered a molecular dimmer switch that helps control the flow of solar energy moving through the plant, which protects the plant from absorbing too much sunlight and sustaining oxidation damage – sort of a plant version of sunburn.

The discovery holds important implications for the design of artificial photosynthesis systems. Systems using today’s artificial solar energy technology can suffer overload damage if they absorb too much solar energy.

Through photosynthesis, green plants harvest energy from sunlight and convert it to chemical energy at a transfer efficiency rate of approximately 97 percent. The highest rate for solar energy conversion to electrical energy using a man-made device today is less than 30 percent. Further study of photosynthesis could lead to higher energy conversion rates.

The dimmer switch is pigment-binding protein CP29, which operates as a valve that permits or blocks the release of excess solar energy during photosynthesis. CP29 is one of the so-called minor light-harvesting proteins in green plants. In addition, researchers have proposed that the valve can be controlled by raising or lowering ambient pH levels.

“This is really the first detailed picture ever obtained of the molecular mechanism behind the regulation of light-harvesting energy,” said Graham Fleming, a physical chemist at the laboratory and the University of California at Berkeley who is one of the leaders of the study...Read the rest