In 2005 NEDO founded the first large scale wind energy storage project in the world. The system was sized at 4MW nominal with a 6MW pulse and 1.5 hours of energy storage. It was operated and ran for 3 years proving the capability of energy storage to smooth the intermittent output of a wind farm. The wind farm consisted of 32MW of Vestas wind turbines and was operated on Hokkaido Island by the utility J-Power. The system was cycled over 270,000 times over the course of 3 years and several control algorithms were developed to control the SOC of the VRB system. This validated the uniqueness of the VRB as a battery capable of having its SOC measured under load at all times. This reduces the sizing as compared with ALL other batteries and also ensures safety of operation by avoiding any overcharging.

Japan VRB technology installations