The Cellular Smart Grid Platform (CSGriP) project aimed to make the electricity grid more reliable by using the grid frequency as communication signal between autonomous cells. By using the grid frequency as a control signal for prosumers (i.e. producers and consumers), no other communication (central or external) is required for safe and reliable operation (e.g. during grid failures, IT infrastructure failures or intended island operation). Renewable Energy (RE) producers and flex consumers are programmed to react to the grid frequency which is determined by local battery inverters of the cells.
The grid frequency of a cell represents the cell health status, where:
- low frequency means an energy shortage: no RE production, high load and/or empty batteries.
- high frequency means an energy surplus: lots of RE production, low load and/or full batteries.
In the CSGriP project the control principles for cell operation and interaction, based on the local grid frequency, have been developed, modelled and simulated. Experiments were performed at ACRRES.
At the Wageningen University and Research wind and solar test site in Lelystad (ACRRES test site) a full functional smart-grid is realized to be able to simulate and test limitless power distribution scenarios by combining different renewable energy sources with different consumers and storage devices. The battery and energy management system (EMS) play a key role in the test site grid, the EMS has the ability to switch each connected device seamlessly to an on- or off-grid circuit, while both circuits maintain fully functional. In the off grid circuit a battery plays an important role of long term energy storage. Grid stabilization, both on- or off-grid, by absorbing pike loads and filling up power gaps can be an additional smart-grid function of a battery. In addition to power storage or buffering, switching the battery directly to the grid opens the possibility to trade energy on the different energy markets.