The Utility Variable-Generation Integration Group (UVIG), formerly the Utility Wind Integration Group, has released an updated version of a summary table detailing markets and market rules for wind energy and capacity in North America.
The document captures the state of the markets as of October, and analyzes data provided by independent system operators (ISOs) and regional transmission organizations (RTOs).
UVIG's report finds that every ISO or RTO and utility in North America that is integrating a large amount of wind power is using wind-plant output forecasts to improve the reliablity and economic operation of their system.
In addition, wind plants are increasingly being allowed to bid in the day-ahead market, and wind generation is increasingly being factored into the economic dispatch process, the report finds.
The California Independent System Operator (CAISO) has used a centralized wind forecasting system since 2004, while the New York Independent System Operator (NYISO), the Midwest Independent Transmission System Operator (MISO) and the Electric Reliability Council of Texas (ERCOT) began utilizing systems in 2008. In NYISO's case, the forecasts have been used for individual wind-plant economic dispatch decisions since May 2009.
ERCOT uses ensemble forecasts and statistical analysis to prepare a wind power forecast with the following inputs: grid-point output from regional-scale and global-scale numerical weather prediction models; measurement data from several meteorological sensors; high-resolution geographical data; and meteorological and generation data from wind projects.
NYISO utilizes the forecasts to determine if enough generation is committed day-ahead to serve the forecasted load. Real-time wind forecasts are integrated into real-time commitment and dispatch.
MISO, on the other hand, uses wind forecasts to inform its reliability unit commitment, for transmission outage coordination, transmission security, peak-load analysis and the potential impact of wind ramps on flowgates, whereas CAISO uses a wind generation forecast as the energy schedule for real-time operations and as a day-ahead forecast advisory.
The UVIG document was compiled by Jennifer Rogers and Kevin Porter of Exeter Associates, with UVIG participation and National Renewable Energy Laboratory support, based on a survey covering PJM Interconnection, NYISO, ISO New England, the Ontario Independent System Operator, MISO, the Southwest Power Pool, ERCOT, CAISO, and the Alberta Electric System Operator.
The full UVIG document can be downloaded here.