WEMAG AG is a German clean energy and natural gas utility. In addition to selling power and gas nationally, it also operates a regional distribution grid in western Mecklenburg, northern Brandenburg and Lower Saxony through its subsidiary WEMAG Netz GmbH. 


WEMAG’s wind-swept grid already has an installed renewable generation capacity of more than 800 megawatt (MW). In 2014 these assets generated more than 100 percent of the energy volume distributed to consumers in the 8,600 km² grid area.





The increasing volume of clean, but intermittent energy feed-in to the grid disrupts the short-term balance between production and consumption. Such fluctuations have to be compensated through the use of positive, or negative frequency regulation power.


If renewable energy penetration on a grid rises above a relatively low threshold, such control power cannot come from conventional thermal power plants, which have to run at about 60 percent of their production capacity to have enough upward and downward flexibility. This so-called “must-run” capacity clogs grids and forces renewable generation units to be taken offline.




We built a 5 MW/5 MWh battery power plant for WEMAG. Located in the Schwerin district of Lankow, the battery park is housed in a hall the size of a school gym. Inside, 1,600 battery “trays” contain 25,600 lithium- manganese-oxide cells that can store and release energy within milliseconds. Five medium-voltage transformers connect the units to the grid and boost the current from 480 volts to 20 kilovolts
and back down as needed.


In late 2016, WEMAG decided to enlarge their battery park. With this upgrade, the utility’s storage resource will triple its power output from 5 MW to 15 MW, while the energy capacity will increase from 5 MWh to 15 MWh. Additional 1,254 modules or 27,588 cells will be installed in a second building.


The battery park earns its keep by competing in primary frequency regulation markets. In addition, we are currently upgrading the battery systems’ functionality to make it capable of black starts, full islanding mode and integrating renewables in grid restoration scenarios.

“We’re delivering proof that high power storage for the stabilization of the power grid is already an attractive business case.”


Thomas Pätzold, Chief Technical Officer, WEMAG AG



The Schwerin battery park was the first commercial battery storage resource in Europe. Since then it has been an active participant in the region’s frequency regulation market. The fact that WEMAG invested another 5 million euros in 2016 to increase the available power and energy for system service is a strong testamonial to the commercial success and performance of battery storage in Europe and the rest of the world.




power provides the same frequency regulation capability as a conventional 50 MW turbine.



contain 25,600 lithium-manganese-oxide cells that can store and release energy within milliseconds.



megawatt-scale battery park in Europe. Stabilizing fluctuations in grid frequency.




Our intelligent software platform Y.Q is at the heart of the system. It includes AC battery management (ACBM), battery power plant management (BPPM) and a SCADA-integrated energy management system. Together, these software systems control the battery cells – both in the interplay of the individual units, as well as the entire array’s interaction with the grid.


This software architecture ensures three critical results. First, the software enables the battery park to automatically provide necessary services at any time. Second, it guarantees that the batteries are always full or “receptive” enough to charge and discharge as required. Third, our software optimizes the lifespan of the batteries by keeping the lithium-ion cells in their “comfort zones” as much as possible – which is why our battery supplier can provide a 20-year performance guarantee.


Delivering this pioneering project on a turnkey basis, we also leveraged expertise in systems integration and the ability to test the intelligent high-power storage unit in our Technology Center in Berlin.