baudrunner's space: Getting more from less
"Philosophy to Science - Quark to Cosmos. Musings on the Fundamental Nature of reality"

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Tuesday, January 22, 2008

Getting more from less

The conversion of sunlight to energy in the photosynthesis of plants is nearly 100% efficient. It has been determined that almost no energy is wasted as heat in the process because the conversion is virtually instantaneous. Logic would dictate that if the conversion of sunlight to energy in silicon solar cells occurred at the same rate then the energy derived from a commercially manufactured product would be substantially greater than current technology is capable of producing from even high-cost multi-crystalline silicon solar cells, which have an efficiency of about 14-16%. Experimental technologies using exotic materials have pushed the efficiency to about 30% but the manufacturing costs increase by a factor of about one hundred, for only twice as much electricity.

Researchers with the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) at Berkeley appear to have finally solved the mystery of why photosynthesis is so efficient. The explanation lies in quantum coherence. In other words, positively reinforcing oscillation, or wave resonance, occurs at the quantum level when sunlight is absorbed by the chlorophyll molecule. This somehow enables the transfer of energies through all the most efficient distribution pathways which are in sync with the source of excitation potential so long as sunlight is being absorbed. Those pathways that are not in sync simply bounce back the excitations coherently with positive reinforcement and no energy loss. These conclusions were derived from results obtained from studying electronic spectroscopy measurements made on a femtosecond (millionths of a billionth of a second) time-scale of the bacteriochlorophyll in green suplhur bacteria.

The result of the Berkely Lab research might lead to considerable improvements in solar cell technology. From the report...

"The photosynthetic technique for transferring energy from one molecular system to another should make any short-list of Mother Nature’s spectacular accomplishments. If we can learn enough to emulate this process, we might be able to create artificial versions of photosynthesis that would help us effectively tap into the sun as a clean, efficient, sustainable and carbon-neutral source of energy."
In my post "humans are just fancy plants" we note the appearance of the chlorophyll molecule. It is depicted this way because it has always been known to have a geometric symmetry which is very conducive to resonance. It has a morphous crystalline-like conformity. It is not alone in establishing a coherent excitation energy because it is embedded in a larger protein which in the green sulphur bacteria is called the Fenna-Matthews-Olson (FMO) photosynthetic light-harvesting protein. Emulation of the photosynthetic process in the silicon solar cell should probably include a similar confinement of each single silicon crystal within which the crystal is coerced into coherent oscillation.

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