Some utility-scale solar projects have been built that take advantage of the surface of the ocean and lakes as an alternative to using more land. However, researchers at the Fraunhofer Institute For Solar Energy Systems have conducted an experiment near Lake Constance — which borders Germany, Lichtenstein, and Switzerland, that may provide another solution.
An agrophotovoltaics (APV) pilot project conducted at Lake Constance has proven that farming and the use of solar panels can be compatible. This dual use of land is not only efficient but reduces the competition for land while providing additional income for farmers.
The pilot project was being carried out on the Demeter farm cooperative Heggelbach. The project used 720 bi-facial solar panels covering about a third of a hectare. One hectare is equal to 2.5 acres. In the experiment, the solar panels were mounted high enough to allow crops planted below to receive almost as much sunlight as they would if the panels were not there.
Raising the solar panels also allowed for farm machinery to be used. After one year, the experiment showed the dual system increased the land’s productivity by 60 percent.
“The project results from the first year are a complete success: The agrophotovoltaic system proved suitable for the practice and costs as much as a small solar roof system. The crop production is sufficiently high and can be profitably sold on the market,” explains Stephan Schindele, project manager of agrophotovoltaics at Fraunhofer ISE.
“APV has the potential to open up new space that is urgently needed for the PV expansion in Germany, says professor Hans-Martin Henning, the director of Fraunhofer ISE, according to Clean Technica.
“At the same time, APV can mitigate the conflicting interests between agriculture and open space PV systems for viable land. Before market readiness, however, other sectors and differently sized systems still must be tested. Also, the technical integration must be further advanced, for example, the implementation of storage.”
The first crops planted were winter wheat, potatoes, celeriac and clover grass. The south-west orientation and the extra distance between the five meter (16 feet) high rows of bifacial glass-glass PV modules ensured that the crops were exposed to uniform solar radiation.
Co-existence of solar and farming is at risk
This pilot project comes at a good time because how farmers are solarizing the land has become a point of contention in many parts if the world. While some farms have embraced solar energy, installing solar panels, pumps, coolers, heaters and more, others have stopped planting crops altogether in favor of solar farms.
Added to the problem is that since 2010, the cost of installing solar on homes and businesses has dropped over 50 percent. And realizing that farms were both homes and businesses, the Solar Energy Industries Association last year published a guide explaining how farmers could turn “unused or underused land into revenue-generation opportunities.”
Karlee Weinmann, a researcher at the Institute For Local Self-Reliance (ILSR), explains the situation on American farmers replacing crops with solar arrays like this: “The prevailing reasons farmers decide to replace crops with solar are because the farmers are getting older or because it’s easier and more lucrative.”
“They’re principally motivated by risk aversion, and less inclined to want exposure to the volatility that might come with a more traditional crop. Risk is a significant part of the calculus in their decisions, at least in the cases I am aware of.”
With farmers turning away from traditional farming in favor of a more lucrative income with managing solar farms, we may be in for a crisis. Additionally, with twenty-four million acres of agricultural land lost to development since 1982, some policymakers aren’t too happy about solar’s agricultural growth.
“Solar makes financial sense for farmers,” Weinmann concluded. “Farming is not an easy business to be in, and it hasn’t really ever been. Solar is a way to buttress that business in a way that also serves the purpose of making our energy economy much cleaner.”