Surplus renewables to cut gas use in Vonovia apartments
German housing giant Vonovia has launched a pilot project to test the use of auxiliary electric water heaters in water tanks using excess renewable energy, when available, instead of gas. The proposal will reduce CO2 generation and reduce domestic energy bills .
Electricity will become the default energy source, gas being used only when there is insufficient electrical power available. Wind turbines currently have to be shut down when there are grid bottlenecks and no more electricity can be fed into the grid and renewable energy is lost as a result.
The electric booster heaters work like immersion heaters and are heating rods installed in hot water tanks.
The pilot, which could affect 300 of Vonovia’s apartment buildings, will commence in Berlin and is being carried out in conjunction with start-up company Decarbon1ze and grid operator 50Hertz.
Vonovia CEO Rolf Buch said: “We have a binding climate path – by 2045 our building stock should be almost climate-neutral. In order to achieve this goal, we rely on practical and innovative methods. In our pilot project, we use the excess potential of renewable energies.”
The company said that an important aspect of the system is transparent and simple billing of heating and electricity prices that are competitive compared to those of gas.
Decarbon1ze installs counting and control modules and balances the load. Knut Hechtfischer, CEO of decarbon1ze, explained: “With our technology, we enable individual addressing, control and balancing of the electrical auxiliary heating close to the system behind the general electricity meter.” He said that this offers new possibilities for the stock of apartment buildings, which is particularly difficult to convert, and allows more people to participate in the energy transition more quickly.