In the fields grows the stream
Photovoltaics is a great thing, but it needs a lot of space. Do we even have that? This is a much-discussed question when it comes to renewable energy. After all, you can't cover entire suitable landscapes with photovoltaic plants. Fortunately, this is not necessary. If you talk to people in the photovoltaic industry, you always hear: the area is not the problem. What is holding back the expansion of photovoltaics today and in the foreseeable future is rather the limited availability of solar panels and the limited availability of well-trained people who can install them. There should be no competition between energy and food sectors to avoid taking additional land away from nature. Replacing agricultural land with photovoltaic power plants is also not a good idea, after all, food should be produced as locally as possible and not be dependent on imports. However, there are promising experiments to combine both: so-called "agricultural photovoltaics" could become a trend that combines many advantages. Photovoltaic panels are installed on large scaffolds directly above the field with many small slits in between. They convert part of the sunlight into electricity and let the other part through to the plants. The scaffolding is dimensioned in such a way that it is still possible to work underneath it even with large agricultural machinery. So, in this way you can earn money twice with the same area: once from the plants and once from the electricity. However, you have to plan this carefully: some plants yield less if you deprive them of part of the light in this way - then ultimately the price of electricity decides whether the matter is financially worthwhile or not. But there are also plants that grow even better with partial shading. This depends not least on the weather. Experiments show that especially in hot, dry years the yield could be increased in this way. Partial shading by photovoltaics protects the plants from heat damage, evaporation decreases, the soil dries out less quickly, and less irrigation is needed. At the same time, the evaporative cooling of the plants also keeps the photovoltaic system cooler, increasing its efficiency. The amount of light that is let through can be regulated - you just have to adjust the angle of the photovoltaic plants. To sum up, this is a rather complex optimization task depending on the weather forecast, the growth process of the plants so far, the soil moisture and the current price of electricity, it may sometimes make more sense to convert more light into electricity, and sometimes it may make more sense to let more light through to the plants. But that doesn't mean that in the future farms will have to solve complicated equations in the morning to calculate the optimal control of the photovoltaic system - this kind of thing can be automated, it's a task made for artificial intelligence breaking down bureaucratic barriers. Agri-photovoltaics has a good chance of becoming a major international trend: like the canopy of a forest, photovoltaic systems could provide partial shade and enable entirely conventional agriculture underneath. But whether this will succeed depends not least on the political framework conditions: is it even possible to erect such structures on land dedicated to agriculture? How much bureaucracy is necessary? Will subsidies or perhaps other subsidies that are currently paid out for agriculture no longer be received because the area is now being used twice? Some ideas are so good that they catch on all by themselves, even if they don't get government funding. But at the very least, efforts should be made not to let the state hold them back. Source: futurezone |
