Satellites help solar power plants anticipate cloud cover, sunlight availability

April 14 (UPI) -- When it comes to cloud cover, weather forecasts offer rather imprecise predictions, making it hard for solar power plants to anticipate sunlight availability.

To solve the problem, scientists have developed a new model -- powered by data collected by recently launched satellites -- to forecast the optical properties of clouds, according to a study published Tuesday in the Journal of Renewable and Sustainable Energy.

The technology, dubbed the Spectral Cloud Optical Property Estimation, or SCOPE, utilizes the observations of several GOES-R series, which NASA began launching in 2016. GOES-R satellites occupy fixed positions above Earth, and they use an Advanced Baseline Imager to measures radiation rising through the atmosphere at specific wavelengths.

By comparing how different wavelengths pass through the atmosphere after reflecting off Earth's surface, SCOPE can estimate a cloud's altitude, thickness and optical depth, or how it impacts the light passing through it.

The water that forms clouds can take a variety of forms, including both liquid and ice crystals. The size of the droplets and crystals can vary widely, each absorbing different amounts of light. How much light a cloud absorbs also depends on the wavelengths of the solar energy passing through.

Cloud composition has a large impact on how much light in the wider infrared range is absorbed. The absorption of light in the narrower visible range is less variable.

Scientists tested the accuracy of their predictive model by comparing their simulation results to real sunlight data collected at variety of ground-based locations in the United States. The results showed SCOPE is quite accurate at predicting the optical qualities of clouds.

Researchers hope the technology will be used by solar power plants to deploy their solar arrays more efficiently.

"SCOPE can be used during both day and night with reliable accuracy," study co-author Carlos F.M. Coimbra, engineer at the University of California, San Diego, said in a news release. "Due to its high-frequency output during daytime, SCOPE is especially suitable for providing accurate real-time estimates of cloud optical properties for solar forecasting applications."