The residential area, known as “Im Erlifeld”, has nine housing blocks, each with 10 apartments of which a third are freehold. By involving the energy supply company Eniwa AG early on in the project, the planners were able to configure the whole area so that the blocks could cover most of their energy requirements on site. In this “self-consumption consortium” (a concept also known in Germany as “Mieterstrom”, or “landlord-to-tenant electricity”), the residents benefit directly from the solar installations on the roofs, with no grid charges, concessionary fees or electricity taxes which increase the price of electricity supplied from the grid.

Just as attractive for residents are the public charging points and high-performance charging stations for electric vehicles as well as vehicles from an e-carsharing franchise, all found on the site. Electricity production and consumption is optimised by demand response tailored to the area. This includes 27 heat pumps and the charging points for electric vehicles. Eniwa worked with a start-up to develop a transparent blockchain-based billing solution. For its demand response, the site requires a battery storage system to temporarily store the excess energy. Ideally, this would be used to accommodate peak loads and for arbitrage transactions.

Requirements for a storage solution:

• High-performance storage system with a high depth of discharge and many guaranteed cycles for a sustainable and long-lasting investment
• Easy installation and modular option for expanding the service