Researchers at the German University of Hohenheim in Stuttgart and Thünen Institute in Braunschweig calculate that agrivoltaics could supply Germany between 169 TWh and 189 TWh electricity annually with installations on about 3% of arable land, but needs political will, financial incentives and storage to grow.
According to their research, 10% of the country's most cost-efficient farms with 'good prerequisites' can help cover around 9% of national electricity demand by locating panels on 1% arable land. "In purely mathematical terms, this could replace 3 nuclear power plants," said Department of Economic-Ecological Policy Modeling at Hohenheim, Jun.-Prof. dr Arndt Feuerbacher.
The team says less than 1% of German arable land is sufficient for the agri-photovoltaic or agrivoltaic systems, 0.7% to be precise corresponding to around 85,000 hectares of arable land. In comparison, if usual ground mounted systems were built instead of agrivoltaic systems, to generate the same amount of electricity it would require around 65,000 hectares of arable land which will then not be used for agricultural production.
"With agri-photovoltaics, it would be mathematically possible to cover around 30% of the entire electricity requirement in Germany," according to Thünen Institute's Sebastian Neuenfeldt. "That would take about 300,000 hectares of arable land, or about 3% of the arable land, which could then produce both electricity and agricultural produce."
In agrivoltaics, since solar modules are mounted on high stilts, the agricultural activity can continue unabated next to and below it as well, providing farmers an additional source of income. However, for the systems to be profitable this electricity will need to be remunerated at €0.083 per kWh, they added.
In addition, one can expect an additional economic cost of €1.2 billion annually that will come from solar panels deployed on high stilts along with loss of yield and other costs in joint management of the areas.
Maximum potential—counted in terms of annual solar radiation and investment costs—exists in East Germany with 'specialized arable farms' with advantage of size. In comparison, farms in Southern and Western Germany arable land farms are smaller in size and will cost more in terms of investment and maintenance costs. Yet these regions are high on annual solar radiation.
Basis results assessed from the sample of agrivoltaic systems studied by the team, they see the impact of reduction of solar radiation available to the agricultural growth underneath to depend on kind of plants being grown. There could be higher yield stability for some plants that get the much-needed shade from harsh sunlight.
"On average, however, crop yields from agri-photovoltaic systems fell by around 40%. However, these yield losses would only have a minor impact on the profitability of the farm. Larger companies in particular would compensate for a sharper decline in the contribution margin from agriculture with lower investment and maintenance costs for the photovoltaic systems," according to the researchers.
For agrivoltaic to pick up as a concept and for it to support both agricultural demand and clean electricity supply, the team argues it will take political will, regulatory support and financial incentives for investments. Storage technologies are equally important.
Findings of their research have been published in the scientific journal ScienceDirect with the title Estimating the economics and adoption potential of agrivoltaics in Germany using a farm-level bottom-up approach.