Two recent reports show that it is technically possible to integrate up to 35% renewable electricity to the United States grid if operational and infrastructural improvements are made.
The National Renewable Energy Laboratory (NREL) have investigated the potential in the eastern and western transmission systems. The first of two studies entitled “The Eastern Wind and Transmission Study” (EWITS) using wind energy to shift over 20% of the power for the Eastern Interconnect by 2024.
No major technical barriers were found to the integration of 20% wind energy into the electrical system, although transmission planning, system operational policy and market development would need to continue to evolve for this penetration level to be achieved.
The second study entitled “Western Wind and Solar Integration Study” (WWSIS) looks at adding wind and solar power to capacity to the grid to produce 35% of the WestConnect’s electricity by 2017. WestConnect is a group of utilities in Colorado, Arizona, New Mexico, Nevada and Wyoming that are working to enhance wholesale electricity markets in the West.
If utilities substantially increase their coordination of operations over wider geographic areas and schedule their deliveries on a more frequent basis, then it is operationally possible to accommodate 30% wind and 5% solar energy penetration in the West.
A study by Alstom Grid reviews the practices of 33 grid operators in 18 countries as they integrate increasing larger amounts of wind into the power grids. The finding show that wind power forecasting is the most important pre-requisite for successful integration, with centralised forecasting the best approach. The grid operators need to be well equipped with the necessary decision support tools in control rooms.