Semi-transparent solar cells boost growth of greenhouse plants• https://newatlas.com, By Michael Irving
Scientists at UCLA have now tested a way to combine the two by placing semi-transparent solar cells on the glass roofs of greenhouses, finding that they can actually improve the growth of plants inside.
Greenhouses and solar energy both need lots of sunlight, so it's no surprise that engineers have experimented with building them into the same structures. Experiments have shown that it's basically a win-win situation – semi-transparent solar panels can produce a decent amount of electricity, while also not starving the plants of their vital sunshine. In some cases the plants even thrived under there.
For the new study, the UCLA team investigated a few tweaks to an existing recipe. They started with organic solar cells, which are made from carbon materials and can be crafted into transparent, flexible solar cells. That sounds perfect for greenhouse use, but the downside is that these organic materials degrade quickly in sunlight.
So the team added a new ingredient – a layer of a chemical called L-glutathione, to prevent the organic materials from oxidizing and breaking down. In tests, organic solar cells both with and without this protective layer were placed under solar irradiation for 1,000 hours of continuous use. And sure enough, those with the extra layer retained over 84% of their original efficiency, while those without it dropped to under 20% in that time.
Next, the researchers put the solar cells to work in model greenhouses, growing wheat, mung beans and broccoli. Each crop was grown in one of two greenhouses – one with a clear glass roof dotted with segments of inorganic solar cells, and the other with a roof entirely consisting of semi-transparent organic solar cells.