On the list of climate-change impacts: hydropower

Hydropower, for many years the leading source of renewable energy in the United States, has hit a rough patch.

The technology, which has produced a reliable, consistent supply of electricity since the 1970s, is confronting severe climate-related drought in some parts of the world. As a result, declining water levels have forced system operators to reduce power generation.

Drought constricted operations at the world’s largest dam, Three Gorges Dam in China, over the summer.

Bloomberg reported: “Low water levels are a problem around the globe. In California, Germany, Norway and elsewhere, extreme heat and drought are wreaking havoc on the ability of dams to generate clean power. The irony isn’t lost on anyone: The effects of climate change are undermining one of our best tools to prevent future warming.”

Hydropower is now the second-leading source of renewable power, producing 6.3 percent of all utility-scale generation in 2021. Wind power produced 9.2 percent in that year.

Hydropower has lost some of its luster in the United States in recent years. While it is a reliable source of renewable energy, more attention has been paid to the impact of the massive structures on the local ecosystem. Hundreds of dams have been removed across the country, the largest the Elwha Dam in Washington state.

According to the U.S. Energy Information Administration: “A dam that creates a reservoir (or a dam that diverts water to a run-of-river hydropower plant) may obstruct fish migration. A dam and reservoir can also change natural water temperatures, water chemistry, river flow characteristics, and silt loads. All of these changes can affect the ecology and the physical characteristics of the river. These changes may have negative effects on native plants and on animals in and around the river. Reservoirs may cover important natural areas, agricultural land, or archeological sites. A reservoir and the operation of the dam may also result in the relocation of people. The physical impacts of a dam and reservoir, the operation of the dam, and the use of the water can change the environment over a much larger area than the area a reservoir covers.”

Bloomberg: Climate Change Is Ruining the World’s Best Source of Clean Energy

CNN: The West’s historic drought is threatening hydropower at Hoover Dam