Regional utility AÜW and Siemens are working with the small Bavarian town of Wildpoldsried, population 2,600, to learn how to stabilize a power grid that integrates large volumes of renewable energy.
The good news and the challenging news for Wildpoldsried is that its renewable energy systems produce 500% more renewable energy than the community needs, the Rocky Mountain Institute reports. The town set out in 1997 to derive 100% of its energy requirements from renewables by 2020, but “things happened much faster than planned—17 years later, the town now has five biogas plants, almost 5 MW of solar PV, 11 wind turbines with a total capacity of more than 12 MW, a biomass district heating network, three small hydro power plants, and 2,100 square meters of solar thermal systems.”
The wind turbines operate on a 10-year payback and generate 80% of the earnings of the dairy farms where they’re located.
“While all this excess renewable energy is bringing in over $7 million a year in revenue, it was also causing a headache for AÜW, which has to maintain grid stability,” Guevara-Stone notes. The solution was to install a network of devices to measure current, voltage, and frequency, helping the utility balance supply and demand.