In this paper, the authors examine the characteristics of a storage system that would be needed to capture all the wind or solar PV energy generated from an increasing level of renewable capacity.
They use data from two US regions to examine systems powered by wind and solar PV, supported by either storage or natural gas-fired generation. The authors find that there is significant regional and resource-related variation in the mismatch between renewable power output and load and that the renewable energy mix will influence the amount of storage needed. They also find that capturing and using all of the wind/PV energy generated would require systems with very high energy storage capability (in terms of MWh) compared to those currently used in storage systems. The conclusions of the paper suggest that in such regions, some additional storage may be beneficial, but avoiding all excess wind generation may be uneconomical.