The National Renewable Energy Laboratory ("NREL") recently announced the release of the "Western Wind and Solar Integration Study" (the "WWSIS"), which investigated the operational impact of up to 35% energy penetration of wind, photovoltaic, and concentrating solar power on the power system operated by the WestConnect group of utilities in Arizona, Colorado, Nevada, New Mexico and Wyoming. The WestConnect group includes the following: Arizona Public Service, El Paso Electric Co., NV Energy, Public Service of New Mexico, Salt River Project, Tri-State Generation and Transmission Cooperative, Tucson Electric Power, Western Area Power Administration, and Xcel Energy.
The WWSIS was prepared by GE Energy and conducted over two and a half years by a team or researchers in wind power, solar power, and utility operations. The WWSIS was designed to answer questions that utilities, Public Utility Commissions, developers, and regional planning organizations had about renewable energy use in the West, such as:
- What is the operating impact of up to 35% renewable energy penetration and how can this be accommodated?
- How does geographic diversity help to mitigate variability?
- How do local resources compare to remote, higher quality resources delivered by long distance transmission?
- Can balancing area cooperation mitigate variability?
- How should reserve requirements be modified to account for the variability in wind and solar?
- What is the benefit of integrating wind and solar forecasting into grid operations?
- How can hydro generation help with integration of renewables?