Worldwide, about nine million acres are covered in greenhouse vegetable production. And that’s roughly the size—two times
the size—of New Jersey. So, that’s a considerable amount. So, we can save an awful lot of climate-changing greenhouse gas emissions if that electricity was generated onsite. A solar greenhouse is a dual-use facility. It can be used for growing plants but it also generates it’s own electricity. That electricity is then used to support functions of the greenhouse. We’ve grown a variety of of different crops, many of which are important to the central California—central coastal region—around
UC Santa Cruz, including strawberries, tomatoes, lettuce. But in this study we found that most species grew just fine under the altered light conditions. The growth of tomatoes and the number of tomatoes was pretty much the same under the pink-colored glass house compared to the clear conventional glasshouse. This technology developed by Sue Carter and Glenn Alers of the Department of Physics at UC Santa Cruz. So, the color of these is because of the dye that’s embedded in windows. And the dye absorbs part of the sunlight and delivers it to thin photovoltaic strips that are embedded in the plastic. And that’s where the electricity is actually
generated. The visible wavelengths of sunlight include all the colors of the spectrum. These panels absorb the green, which plants don’t use, and part of the blue. And that’s part of why we weren’t sure
how plants would grow and develop, because plants like blue light and they like red light. When we measured photosynthesis, we also get a measurement of how much water the plants are using. And we find, actually, that they use about
five percent less water when they’re growing underneath the pink glasshouses. If you multiply that by nine million acres
globally, that’s a potential huge amount of water savings.