Droughts are cutting into California’s hydropower. Here’s what that means for clean energy.

The environmental impact of hydropower is often under scrutiny. California doesn't count large hydropower plants in its renewable-power targets. Regardless of how it is categorized, hydropower is an alternative to fossil fuels.

Brian Tarroja is an energy researcher at the University of California, Irvine.

Several transmission lines in California were affected by the Bootleg fire in Oregon last year. While ramping up natural-gas plants was barely enough to keep the power on, hydropower plants were running at their reduced capacity.

Tarroja says that these difficulties are likely to continue. Climate change is causing higher temperatures even if precipitation stays the same. The llenge hydropower is likely to be affected in the future.

Climate change may affect power generation in places with high levels of hydropower. In the last few years, the capacity of hydropower in Brazil and China has been threatened.