Cloud forecasts could gauge energy needs Cloud forecasts could gauge energy needs - Science updated 2 hours 23 minutes ago Cloud forecasts could help estimate energy needs Predictions would let power companies know what to expect from solar panels during day You've heard of weather forecasts, but what about a forecast that predicts the shape, size and thickness of clouds? Such predictions could help power companies learn how much energy they should expect to get from solar panels throughout the day, according to the Pacific Northwest National Laboratory. The lab, based in Washington state, has developed a method that is able to predict the properties of clouds from five minutes to about an hour ahead of time. The method also assesses how much solar radiation will reach the ground. Power grids work best when they have a steady supply of electricity, but solar energy is anything but constant. Sunlight peaks and fades throughout the day depending on the clouds in the sky. Cloud forecasts could help power companies prepare for sudden bursts of sun - and electricity - entering their systems, as well as for cloud cover that may require them to lean more on other energy sources, such as a coal or nuclear power plant. Charles Long, a climate scientist at the Pacific Northwest National Lab, developed the forecasting method along with his colleagues. The method uses data from pyranometers, sunlight-measuring devices originally developed for climate change science. Long presented his work Dec. 4 at the annual meeting of the American Geophysical Union in San Francisco.