German energy company E.ON has calculated that 90 million square meters is available on the roofs of supermarkets, logistics halls, furniture retailers and DIY stores for the installation of solar PVs across Germany.
The space is equivalent to 10,000 football pitches and enough to generate 6750 MW of solar PV capacity. This, says E.ON, is enough energy to retire eight coal-fired power stations in Germany.
To unlock this potential, E.ON says it is vital to enable equal treatment of rooftop and ground-mounted systems, which is not provided for in the amendment of the Renewable Energy Sources Act (EEG) currently under discussion.
For rooftop PV systems of between 500 and 750 kilowatts (kW), for example, a specific tendering segment is to be created, which would impose more stringent regulations than those applicable to ground-mounted systems.
If these unequal conditions remain, E.ON argues that more PV systems will come under the obligation to feed all of their electricity into the grid, making it more difficult for many medium-sized companies to pursue a sustainable corporate strategy.
Karsten Wildberger, E.ON’s chief operating officer responsible for customer solutions, said: “Trade and industry can make a significant contribution to the energy transition with their own climate strategies.
“However, the conversion and operation of energy infrastructure must not be a burden on companies, but must be economically viable. The technologies are available. What is now needed is the right legal framework.”
According to the current draft of the amendment, a medium-sized company wishing to implement its own individual climate strategy with on-site PV installations must feed the power generated into the grid if the PV system is designed to produce more than 500kW.
This means it wouldn’t be able to use the power for its own production processes, and on top of this the company would have to take time out from its core business to participate in a highly bureaucratic bidding process.
In the current debate about the amendment of the EEG, however, there is no legal certainty for this business model. Differing legal interpretations of who can be considered the operator of a power generation system threaten the investment security of many existing and future operator models.