The State of Washington Hydropower

Washington just released the 2023 Fuel Mix Report, which shows our state's electric utilities aggregate fuel mix:

While utility companies in the state of Washington still get more power from hydro than any other source, the number of gigawatt hours and the percentage of our power derived from hydro are both trending downward. 2023 marked the first year that electricity consumers in the state of Washington received less than 50% of its power from hydro. The reduction in hydro consumption is a byproduct of legislative changes to curb demand/production and climate changes that have reduced supply.

As electricity demand is rising, hydro is making up a shrinking portion of our power portfolio.

Recent Legislation in Washington impacting Hydro

A list of laws enacted in Washington that have impacted hydro production includes the following:

1. Washington Renewable Portfolio Standard (Initiative 937 - 2006)

   • Required large utilities to obtain 15% of their electricity from new renewable sources (excluding most existing hydropower) by 2020.

   • While it promoted diversification, it limited the ability to count existing hydroelectric power toward the target.

2. Clean Energy Transformation Act (CETA) (2019)

   • Mandates that Washington transition to 100% clean electricity by 2045.

   • While hydroelectricity qualifies as a clean energy source, the law also encourages diversification with wind, solar, and battery storage.

3. Salmon Recovery and Environmental Regulations

   • State and tribal efforts to restore salmon populations have led to dam modifications, increased water spills, and changes in water flow management, reducing the amount of water available for power generation.

Climate Change Impacts to Hydro

Over the past decade, climate change has significantly impacted hydroelectric power production in Washington State and the broader Pacific Northwest. The main effects have been:

1. Reduced Snowpack and Earlier Snowmelt

• Declining snowpack in the mountains, a critical water source for hydroelectric dams, has been a major factor. Warmer temperatures lead to less snow and earlier snowmelt.

• Earlier runoff means that water may not be available during the summer when demand for electricity is high, limiting power generation during peak demand periods.

2. Increased Drought Frequency

• More frequent and severe droughts due to higher temperatures and changing precipitation patterns have reduced river flows and water levels in reservoirs.

• This decreases the available energy for hydropower generation and forces utilities to rely more on other sources of electricity, such as fossil fuels.

3. Changing River Flows

• Fluctuating river flows caused by erratic weather patterns, such as extreme rainfall or droughts, have made power generation from hydro more unpredictable.

• High flows can damage infrastructure, while low flows can limit power output.

4. Environmental and Ecological Impact

• Warmer water temperatures and altered river ecosystems impact fish populations like salmon, which require specific conditions to thrive. Environmental regulations often require more water releases from dams to protect fish, reducing the power available for generation.

  
  

Conclusion

Despite these challenges, hydropower still plays a crucial role in the region's energy mix, but its contribution has been impacted by climate change and legislative priorities. 2022 saw some of the lowest hydroelectric output in two decades in the Pacific Northwest due to low river flows and drought conditions. Adaptation measures like upgrading dams, better water management, and increasing reliance on other renewable sources like wind and solar are part of the response to these changes. Because the price utilities pay to convert hydroelectric power for our everyday electricity consumption has been the primary source of cheap power for residential and commercial consumers in the PNW, we should expect the impact of these trends to increase what we pay for our power for the foreseeable future.