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Researchers at the University of California use semi-transparent organic cells for this purpose
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Test greenhouse on UCLA campus (Photo: Yang Yang Labor, ucla.edu) |
Los Angeles (pte002/08.03.2023/06:05) –
Greenhouses produce thanks to a development by researchers at University of California, Los Angeles (UCLA) will in future use the light of the sun to generate the electricity that is required in the associated horticultural or agricultural business. At the same time, they are protected from excessive radiation. This is achieved with solar cells that are mounted instead of the glass roof. Silicon cells would not be suitable because they do not transmit the light that plants need to survive. Instead, the developers rely on semi-transparent organic cells that don’t let through more light than the plants need.
dietary supplements
Semi-transparent organic cells are nothing new in themselves, but they often don’t stand up to the harsh rays of the sun for very long. Materials scientist Yang Yang and his team from the UCLA School of Engineering enriched an organic cell with a layer of the naturally occurring chemical L-glutathione, which is sold over the counter as an antioxidant dietary supplement.
This approach extends the life of the solar cells, improves their efficiency and still allows enough sunlight through. “Organic materials are excellent for photovoltaics because of their light absorption selectivity. Their main drawback, which has prevented their widespread use, is their lack of stability,” says Yang, who also works in bioengineering.
Winner in the comparison test
Organic solar cells tend to degrade faster than their inorganic counterparts because sunlight oxidizes organic materials, causing electrons to be lost. This is exactly what L-glutathione prevents. The cells modified in this way still had a residual efficiency of 80 percent after 1,000 hours of operation. Without this chemical, the efficiency drops to 20 percent in the same time. The researchers still have to do something to improve the stability of the cells.
They tested their solar cells and silicon cells, which they gapped to let light through, on two small greenhouses where they grew plants. They grew better under the organic roof than under the inorganic one. That’s because the L-glutathione layer blocks UV rays, which can stunt growth, and IR rays, so greenhouses don’t overheat. The developers have now founded a start-up that wants to produce the organic solar cells and market greenhouses equipped with them.
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