The impact of climate
change on hydropower

The effect of climate change on hydropower

There’s no denying that climate change is likely to fundamentally impact how we generate energy and maintain our grid. In the Northwest, roughly half of all our energy is supplied by hydropower. By harnessing the power of the Columbia River and its tributaries with a system of hydroelectric dams, the Northwest has carved out a sustainable way of life for all who call it home. For that reason, potential threats to that hydro system should not be taken lightly.

Across the United States and around the globe, there are questions about just how vulnerable our energy supply is to climate change. This does not exclude hydropower. Particularly in the Southwest region, drought has threatened to dry up the water supply for hydroelectric dams. Without these reservoirs, the generation of energy slows to a halt and access to water for drinking and irrigation is threatened.

Headlines and images shared in the media and online have only further heightened the worry that the warming climate will dry up our rivers and reservoirs and reduce our hydropower output to zero. At the same time, events like those that have taken place in California and Texas more recently have provided a look at what energy shortages could look like elsewhere in the United States.

Fortunately, the aforementioned hydropower facilities of the Southwest have withstood these droughts thus far and record-setting precipitation in the beginning of 2023 has replenished the water supply. Still, with more warming expected due to climate change, it’s reasonable to wonder what the future holds.

Climate predictions

In the Northwest, however, these same sorts of drought conditions are expected in the years to come. Rather, scientists predict warmer, wetter winters. While more water sounds good, climate change will increase temperatures and reduce snowpack in the Pacific Northwest.

As we enter the summer, that snowpack is essential to providing a consistent flow of water into our rivers. While dams have reservoirs that have some storage capabilities, snowpack is a natural storage system that is important to energy generation year-round.

Less snowpack means less water will be stored to fuel hydropower through the later parts of summer. And, with the increase in temperatures, more heat waves are expected to occur, leading to higher electricity demands during the summer months and increased demand for electricity from hydroelectric power.

In essence, as the environment changes, seasonal water flows may no longer coincide with times of greatest demand for power.

This could also negatively impact the water supply for irrigated agricultural farms that draw water from dam reservoirs during those same summer months.

The issue of resource adequacy–or the ability to maintain energy supply to meet energy demands at all times–will be further challenged as the region continues to pursue electrification in areas like transportation.

All of these challenges to the Northwest’s hydropower supply aren’t expected to render it useless, but during times of frequent and sustained heat in the summer, it may strain the system and introduce the risk of energy shortages.

Hope through hydropower

Despite this concerning outlook, there is hope through hydropower as well.

Hydro may supply around half of our energy in the Northwest, but it is responsible for up to 80% of our renewable energy supply. It is the cornerstone of our clean energy transition, which is critical to the fight against climate change.

How hydropower can help fight climate change:

  • Hydropower provides a firm source of energy that can balance our grid, which helps us add more intermittent renewable resources like wind and solar.
  • Hydropower is a reliable source of clean, carbon-free energy.
  • Hydropower helps reduce reliance on fossil fuels in our transportation system by allowing for the barging of crops and goods from inland ports to the Pacific Ocean

In particular, hydropower’s ability to help us expand our renewable energy portfolio with wind and solar makes it uniquely valuable to decarbonizing the grid.

At all times–meaning 24/7 and 365 days of the year–the grid requires a perfect balance of supply and demand. If there is too much energy, or not enough, energy infrastructure can fail, and blackouts can occur. Providing this perfect balance is no easy task with intermittent energy resources. Energy demand rarely aligns with the supply of wind and sunshine. While batteries seem like an easy solution, the technology is still years away from largescale use. Instead, the Northwest’s dams are being utilized like giant, clean water-powered batteries.

With a hydroelectric dam, if the winds slow down and solar rays diminish, the dam can pick up the slack, harnessing the potential energy stored in water for electrical production. Likewise, when the wind picks up and the sun is shining, the dam can put a pause on generation and hold back water for use at a later time.

Even run-of-the-river dams, which are common in the Northwest, can be utilized in this way despite the fact they do not create true storage reservoirs.

All of this is being done at a relatively low-cost as well since these facilities have been in places for decades already. Keeping these costs down helps the Northwest maintain its lowest in the nation electricity rates. With climate change expected to drive up costs and energy usage, these low costs are essential to protecting low-income and vulnerable communities.

Where we stand

The Northwest is uniquely positioned to make significant progress in combating climate change. As global temperatures continue to rise, we have the potential to leverage hydropower as an integral tool to fight against the damaging effects of climate change and reduce our reliance on fossil fuels.

Overall, climate change is a threat to Northwest hydropower and our ability to generate renewable energy in this region. It is important for us to focus on climate change solutions, effective management of our energy resources, and continued support for existing hydropower facilities that are resilient and reliable. The use of this powerful, water-fueled energy source will be critical to both enduring and pushing back against climate change.

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