Generating solar energy and growing crops in a greenhouse can easily be combined, say the researchers from the American UCLA University in the scientific journal Nature Sustainability.
They used special solar cells made from an organic material in the roof of a greenhouse. To protect the solar cells so that they last longer, they added the natural substance glutathione. As a result, less infrared and ultraviolet light shone on the plants, which had a positive effect on growth. Ultraviolet rays can inhibit plant growth and infrared light can cause greenhouses to overheat, causing plants to need more water.
The researchers grew wheat, mung beans and broccoli in the greenhouse. “We repeated the experiments several times, with the same outcome,” says lead researcher Yepin Zhao. “We found that plants don’t need as much sunlight to grow as we originally thought. Too much sun exposure can actually do more harm than good.”
Solar cells maintained efficiency
Organic solar cells tend to break down faster because the organic materials oxidize. However, the scientists say that the extra layer of the glutathione prevented the other materials in the solar cell from oxidizing. The organic cells maintained over 80 percent efficiency after 1,000 hours of continuous use, a much better score than without the added layer.
The research team has set up a start-up to kick-start the production of the organic solar cells, so that the environmentally friendly greenhouses can really come onto the market.