Location of implementation:
The city of Grafing bei München is a rural city accommodating about 13.000 people in Bavaria, Germany. The surrounding district of Grafing is Ebersberg. The kick off conference of AlpStore took place in Grafing.
Partially operate village Grafing as a self-sufficient cell with gas and battery storages; gas car to use wind or bio gas.
Since 2011, the local power supplier Rothmoser uses biogas from a biogas plant to operate combined heat and power plants (cogeneration). The substratum, input of the plant, is composed of local farmers’ manure, plant remains and corn – grown by the biogas plant operator. Within ten days, the substratum releases biogas by fermentation; then the farmers can take the fermentation residue back to fertilize their fields. There is a biogas pipeline between the biogas plant and the cogeneration plants, which are associated to two independent district heating networks. Currently, the biogas plant is not driven at its full capacity, due to a permission that is only sufficient to cover its present lower capacity. To be allowed to produce more biogas, the mayor needs to issue a new permission; but this has been denied until now because of some townspeople’s protests.
Within the project AlpStore, the FfE, regional partner of Rothmoser, is considering the possibility of decoupling the power and heat generation. Various benefits –as an independent electricity supply of Grafing, an increased portion of renewable produced energy or decreasing energy prices– can be obtained with such a decoupling. Different storage technologies are being studied, such as a downhole heat exchanger, super isolated water tanks or biogas holders – according to measured and calculated load profiles.
In an upcoming survey, Grafing’s inhabitants will be asked about their acceptance of these technologies as well as about their preferences and main criteria concerning a storage solution. Their willingness to change energy consumption habits will also be requested.
Furthermore it is planned to investigate storage-possibilities in the city. An optimisation of the combined heat and power grid shall show the potential of storages.
Energy turnaround in Germany can only work with the support of the citizens which are affected in one or another way. Therefore a survey addressing the energy turnaround and especially energy storage topics is conducted among the citizens of Grafing.
Another topic is the simulation of the heat distribution grid and the electric grid to find out which energy storage can support the local grid in times of fluctuating energy supply and demand (biogas storage, heat storage).