In order to better quantify the value proposition of wind power combined with energy storage, Vestas connected two lithium ion systems to its 12 MW Lem Kær Wind Plant in western Denmark. The demo features a 1.2 MW/ 300 kWh and a 400 kW/ 100 kWh system from different companies. The system has been approved by the Danish Transmission System Operator for primary reserve market participation.

Lithium-ion Battery