In a recently published study for the German Federal Ministry of Transport and Digital Infrastructure, "Spatially differentiated land potential for renewable energy in Germany," the land potential for ground-mounted solar PV systems was investigated.
With the scientists assuming that 2.2 hectares would be required per installed MW, the study concluded that around 316,400 hectares of land classified as restriction-free could be utilized, representing just 0.9% of the countrys landmass. Overall, 45.7% of available land in Germany is classified as having limited usability.
Graphic taken from p.114 of the study
The areas where the solar PV systems could be installed were concentrated in two regions: north west Saxony and North Rhein-Westphalia. This can be attributed to the quality of the databases in the two regions. Across Germanys federal states, fixed categories in regional planning differ, sometimes considerably. Unlike others, Saxony, for example, has designated priority areas for PV usage.
Regarding available land, which could be used for solar PV, the study differentiated between soft (5,182,461 hectares) and hard (11,150,644 hectares) restrictions. Taboo areas for PV in Germany, said the study, totaled more than 19 million hectares.
The scientists also evaluated rooftop solar PV system potential in Germany. Overall, they calculate that a further 150 GW could be installed. However, in this category, solar thermal is a competitor. In the event that heat generation will be given priority in residential buildings, rooftop PV potential is reduced to 89 GW.
How much of the technically available potential will be used, remains open, however. The goal to install a cumulative capacity of 65 GW by 2030 could be achieved if just two-thirds of owners with suitable rooftop space, would invest in solar PV.
Translated and edited by Becky Beetz