Kronos Solar, a German solar farm developer that has developed sites in the UK, calculated that there are 22,135 brownfield sites in the UK that are theoretically suitable for solar farm development in terms of sunlight levels.
However, 21,488 of these sites are lower than 10 hectares are therefore not viable as they are below the scale required to balance out high costs of connecting to the grid, the company claims.
All but 21 of the remaining 647 sites are unsuitable as they are already allocated for other uses such as housing or are located in flood zones or urban areas, according to the company.
The findings appear to call into question government guidance for solar farm development to be targeted at brownfield sites.
Planning guidance on renewables published by the government in July states that solar farms should only be built on greenfield land if it allows for continued agricultural use and supports biodiversity around arrays.
Kronos Solar managing director Alexander Arcache said that limiting large-scale solar to brownfield land would mean the "certain death" of the UK’s large-scale solar sector. "We need greenfield solar, if we only develop on brownfield, we will miss our renewable targets", he said.
But the Solar Trade Association (STA) questioned the methodology used by the developer, which is not one of its members. STA consultant advisor Ray Noble said that approximately 800 fields need to have solar farms sited on them by 2020 to meet government renewable targets.
There are already at least 100 fields developed, he said. "I’m sure there are enough sites out there that are a mixture of brownfield or low-grade agriculture".
The industry recommends that solar farms are located on flat ground and screened by vegetation.
The STA is due to publish best practice guidance on the siting of solar farms this week.
The report can be read here.