Project Development, Storage, Wind Power

NCAR Forecasts To Help Xcel Harness Wind

The National Center for Atmospheric Research (NCAR) has reached an agreement with Xcel Energy to provide highly detailed, localized weather forecasts to enable the utility to better integrate electricity generated from wind into the power grid. The forecasts will help operators make critical decisions about powering down traditional coal- and natural gas-fired plants when sufficient winds are predicted, allowing the utility to increase reliance on alternative energy while still meeting the needs of its customers.

The U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) will support the project by developing mathematical formulas to calculate the amount of energy that turbines generate when winds blow at various speeds.

NCAR will use a suite of tools, including computer models, to issue high-resolution wind forecasts for wind farm sites every three hours. If the prediction system is successful, wind forecasting companies may adopt the technology to help utilities in the United States and overseas transition away from fossil fuels.

“One of the major obstacles that has prevented more widespread use of wind energy is the difficulty in predicting when and how strongly the wind will blow at the wind farms,” says William Mahoney, the NCAR program director overseeing the project. “These forecasts are a critical step in getting more energy from wind.”

Because large amounts of electricity cannot currently be stored in a cost-effective manner, power generated by a wind turbine or any other source must be promptly consumed. If an electric utility powers down a coal- or natural gas-fired facility in anticipation of wind-driven energy, those plants may not be able to power up fast enough if the winds don’t come as predicted. The only option in such a scenario is to buy energy on the spot market, which can be very costly. Conversely, if the winds blow more strongly or erratically than anticipated, the surge of energy can overload the system. NREL will help Xcel Energy predict the resulting energy output.

“The utility is interested in the potential power coming from these large wind sites, but every wind turbine on the site will not have the same wind speed,” said Erik Ela, NREL engineer. “NREL’s models will convert the wind speed into power and give the utility better information on how much electricity the entire wind site will generate.”

The project builds on forecast technologies that NCAR has successfully developed for the U.S. military, National Weather Service, aviation industry, overseas governments, and other organizations in the public and private sectors.