Experts agree that solar PV and wind power are equally needed to support the energy transition. The two technologies are rarely located at the same site, but this could change in the future.

At least, that is the dream of Werner Palm, the managing director of Swiss mounting system manufacturer Smartvolt AG. The company is now working with German wind specialist Westfalen Wind, which has deployed an innovative 96.8 kW pilot PV project in the gravel crane parking area of a wind turbine. The two companies used a Smartvolt mounting system to deploy pre-assembled solar module strings, which can simply be folded out on site.

“Thanks to our patented crane beam, it can be erected in three minutes per kilowatt, and dismantled in around six minutes,” said Palm.

The PV system can be easily dismantled if the wind farm’s floor space is needed for maintenance work, he noted.

“As a rule, this is only necessary once every 20 years,” added Daniel Saage, the managing director of Westfalen Wind.

Then the solar modules can be folded up and installed again after the maintenance work has been completed. Thus far, Smartvolt has not subjected the system to a long-term load test.

“But five to 10 times shouldn’t be a problem,” Palm said.

Both companies see the advantages of this combination because the technical infrastructure to connect the PV system to the grid via the wind turbine is already in place. In addition, there are no additional space requirements and an area that has already been sealed can still be used. The annual yield of the PV system is around 85,000 kWh, which could cover around two-thirds of the wind power plant’s own requirements per year. This is around 96,000 kWh and is usually generated by the wind turbine itself.

The local network operator has agreed to approve the PV project as a classic self-consumption system. Whenever the wind turbine is not spinning, its own electricity requirements can be covered with photovoltaics, which ensures that the wind generator is significantly more profitable.

However, Saage said bureaucratic factors are still preventing a breakthrough. The pure manufacturing costs for a 100 kW system are around €600 ($730) per kilowatt installed. In addition, there are building permit fees and compensation payments, as well as other costs. But if such obstacles are eliminated, a few hundred kilowatts of solar could be installed at wind farms without additional costs.

“This would significantly reduce costs and make the overall concept more economically attractive,” he said.

Westfalen Wind has said that around one-fifth to one-eighth of crane parking space could be used for PV systems. However, the wind turbines towers must not face south – ideally, the PV systems should be built with an east-west orientation. In the German state of North Rhine-Westphalia alone, Saage sees the potential for 60 MW of solar at crane parking areas. Throughout all of Germany, capacity could reach 300 MW, he added.