One of the three towers at the 392-MW Ivanpah concentrating solar power (CSP) plant is offline after sustaining damage due to a small fire Thursday morning. The San Bernardino County Fire Department posted a photo showing melted and burnt steam ducts at the tower. The department received reports of the fire at unit 3 of the solar park just after 0930 local time.

The fire was extinguished quickly and there were no injuries to civilians or fire-fighters, the department reported. The cause is currently under investigation. The Associated Press quoted fire captain Mike McClintock as saying that misaligned mirrors may have focused sun-beams on the wrong section of the CSP tower, with electrical cables catching fire as a result. The CSP park in the Mojave Desert is a partnership between NRG Energy (NYSE:NRG), Google (NASDAQ:GOOG) and BrightSource Energy Inc. For many months it has been unable to meet the output levels agreed in its power purchase agreement (PPA). It was given an extension until July 31, 2016 to improve performance.

Image credit: San Bernardino Fire Department

Read more: Fire shuts down Ivanpah Unit