As photovoltaic (PV) solar power systems become more widespread in Europe, the search for suitable sites (where there is little or no land conflict) has led to the emergence of floating PV systems on artificial bodies of water. In some countries, like the Netherlands, floating power stations have been built on a large scale, whereas in Germany, there are only a handful of pilots.
The Fraunhofer Institute for Solar Energy Systems (ISE) in Freiberg recently estimated that Germany’s lignite opencast mining lakes offer the technical potential for 56 GW of floating PV systems. There are 500 such lakes in Germany, mostly in the states of Brandenburg, Saxony-Anhalt and Saxony – a total potential area of 47,000 hectares. But not all the sites are viable. After deducting the areas that could be used for leisure, tourism, nature and landscape conservation, the report put the true economic potential at just under three gigawatts.
As the cost for floating PV systems is on average 10 to 15 percent higher than land-based, there is little incentive at the moment for the technology to be developed at scale in Germany. The Fraunhofer scientists are therefore calling for increased incentives for these systems. In the Netherlands, for example, there is a compensation for land use scheme.
To meet Energy Transition targets, up to 500 GW of PV capacity are needed – in other words, a tenfold increase in the current number of plants. "Floating PV power plants are a relatively new concept… but one for which there is great potential for electricity generation worldwide, not least because they allow for expansion without affecting the area", said Andreas Bett, head of the Fraunhofer ISE, talking to .
There are other advantages too – floating plants could deliver higher yields compared to ground-mounted systems, due to the cooling effect of water. There are an estimated 4,474 artificial water bodies in Germany which could be considered.