Climate change-fueled heatwaves and droughts have shrunk rivers that feed giant hydropower plants around the world.

This summer, the world’s largest power plant was eerily quiet. The Three Gorges Dam in China is a magnificent structure that spans the Yangtze River and is so large that it could cover seven Wembley Stadiums with concrete and eight Empire State Buildings with steel. The Philippines might be entirely powered by its turbines.

However, in late August, the water was still on both sides of the dam. Neither the typical white spray rising from the spillway nor the boom of water coming from the turbines could be seen. The reservoir has been considerably depleted due to extreme heat and a drought upstream, which has significantly decreased the plant’s capacity to produce energy.

The water woes of China’s iconic mega-dam are part of a global hydropower crisis that is being made worse by global warming. From California to Germany, heatwaves and droughts have shrunk rivers that feed reservoirs. Hydroelectricity output fell by 75 terrawatt-hours in Europe this year through September — more than the annual consumption of Greece — and fell 30% across China last month. In the US, generation is expected to fall to the lowest level in six years in September and October.

Hydropower is being reevaluated

Utility companies are being forced to reevaluate hydropower’s historic position as a dependable and quick source of green energy due to a harsh irony. Despite being the greatest source of renewable energy in the world, dams are becoming less useful in the fight against climate change due to harsh weather.

The issue is that there aren’t many green options that are equally accessible or versatile. On a global scale, hydropower produces more electricity than nuclear power and more than wind and solar power put together.

Greenpeace informed that hydro’s struggles underline the difficulty of building a robust renewable energy network to replace fossil fuels, especially in developing nations that must also contend with soaring electricity demand as per-capita consumption rises. At the same time the drought issues underscore the need to speed up efforts to curb rising temperatures as the cost of making the energy transition mounts.

We need to recognize there will be things we can’t prepare for or are too expensive to plan for. If we don’t address the issue at the core of climate change and cut emissions catastrophic losses will occur.

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Originally published in Bloomberg