Scientists to provide Xcel with US wind forecasts

NEW YORK Feb 4 (Reuters) - Atmospheric researchers based in Colorado said on Wednesday they will provide Xcel Energy Inc (XEL.N) with detailed wind forecasts every three hours to help maximize power generation from the alternative energy source.

"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," William Mahoney, the program director of the National Center for Atmospheric Research, said in a release.

Under the agreement, NCAR will develop a prototype wind forecast system over the next 18 months and generate predictions for Xcel wind farms in Colorado, Minnesota, New Mexico, Texas, and Wyoming in six months. Terms of the deal were not disclosed,

Xcel spokesman Tom Henley told Reuters the utility hopes to save $10 million to $12 million in the first two years of the program and that it should pay for itself within the first year.

The issue of maximizing wind power generation has come into focus as nearly 30 U.S. states have set minimum levels of electricity generation from renewable sources like wind and solar power -- known as Renewable Portfolio Standards -- to reduce emissions of greenhouse gases from the burning of fossil fuels.

But the wind is fickle.

"Wind energy remains difficult to manage due to its variability -- you can't always count on it," said Eric Pierce, Xcel Energy's managing director of energy trading.

Less than a year ago, a power grid operator in Texas was forced to cut service to industrial customers when the West Texas wind suddenly stopped blowing.

A multitude of factors can affect wind, including ground cover, temperature changes -- even the number of leaves on nearby trees.

To generate the forecasts, NCAR will use atmospheric observations from a variety of sources, including satellites, aircraft, weather radars, ground-based weather stations, and sensors on wind turbines.

The U.S. Department of Energy's National Renewable Energy Laboratory will support the project with formulas to calculate the amount of energy that turbines generate when winds blow at various speeds.

NCAR hopes its forecasts will help utilities decide better when and how to power down their power plants that burn fossil fuels including coal and natural gas. (Reporting by Timothy Gardner, editing by Marguerita Choy)