Viessmann finalizes unsubsidized 2 MW solar park in Germany

After almost five months of construction, Germany-based manufacturer of heating, industrial, and refrigeration systems, Viessmann has commissioned a 2 MW solar PV park at its headquarters in Allendorf, Hessen, central Germany.

The 7,400 solar modules will deliver 1.8 GWh of solar power annually, according to the company. This increases Viessmann's own electricity production by 50%.

About one-fifth of its electricity is currently being self-produced, a spokesperson told pv magazine. The additional 7% generated by the PV system is to be consumed for the most part directly at the site in Hessen by the unit, Viessmann Werke Allendorf GmbH.

The big news about the project, is that it was developed completely outside of the German renewable energy law (EEG) subsidy scheme. The solar plant, in fact, is planned to deliver the surplus solar power, which is not self-consumed, to other companies of Viessmann.

A small proportion of the surplus should also be injected to the spot market, the spokesperson further explained. For direct self-consumption, an EEG levy of 40% will be paid, they said. The subsidiary companies, which would also be supplied, would have to pay 100% of the EEG surcharge – which currently amounts to 6.79 cents per kWh for solar power.

The amortization of the PV system will be made depending on the development of the price of electricity “within a few years”, the spokesperson continued. As a consumer, Viessmann will also benefit directly from cost savings in terms of electricity.

Currently, further projects within the company are being examined. “There are also already the first requests outside the group,” said the spokesman.

However, Viessmann further explained that the planning and implementation of the PV project were carried out with the latest technology. For example, a detailed 3D model of the terrain was created to perfectly harmonize the components.

An exact image of the system's structure was also digitally stored on a computer, which should now facilitate the monitoring and maintenance. This was accompanied by significant time and cost reductions during construction, the company said.

In addition to PV, Viessmann also used biomass and biogas at its headquarters, which support its own electricity and heat supply. The company is not yet considering the expansion of PV systems with battery storage systems.

“Since the surpluses take place only on weekends in the summertime / holiday season, batteries are currently not economically feasible. An additional use of the power-to-gas plant at the site is still under review,” said the Viessmann spokesperson.