Professionally, Carsten Fischer operates on teeth and jawbones. Away from work, Mr. Fischer is passionate about generating heat and electricity for his home in North Rhine-Westphalia, entirely on his own.
He is almost completely independent of utility companies – even in winter – thanks to a solar collector, storage battery and an electricity-producing block heat power plant in his cellar. Mr. Fischer is now linked to the local energy grid only as a backup.
“I’ve got everything in my own hands,” he said.
It is no longer a far-fetched dream for homeowners to become their own energy suppliers. Expensive storage batteries – an essential element in energy independence – are rapidly dropping in price. They make it possible to store electricity generated by the sun for use in nighttime hours.
German business weekly WirtschaftsWoche asked energy consultants NRW to calculate how much self-suppliers would have to invest in home power plants to go off the grid – and how long it would take for their investments to pay off.
In the best-case scenario, homeowners can achieve 80-percent independence with systems that are paid off in 11 years. That requires a photovoltaic system combined with a heat pump and lithium storage battery. Total cost would be €34,000, or about $39,000.
The battery could be financed with a loan from the state KfW Bank, which pays €600 in subsidies for each kilowatt produced by solar roof generators. If an existing facility is improved, the subsidy rises to €660 per kilowatt.
Last year, the price of super-efficient lithium-ion batteries dropped 9 percent, while lead batteries fell almost 35 percent, according to EuPD Research. The decline in prices means home energy plants can pay for themselves more quickly, according to NRW.