By Dr. Kelley Cullen
Electricity consumption, which is vital for firms and households, is made possible by a wide variety of fuel sources depending on the unique geologic, economic and even historic features of the region. The Tri Cities is fortunate to have a relative abundance of access to hydroelectric sources and to sources of nuclear power that comprise the bulk of the fuel mix profile for the combined counties. However, the increased use of renewables and fossil fuels could create challenges with the accompanying greenhouse gas emissions.
Each electric supplier, or utility, serving retail customers in Washington must disclose to its customers the mix of fuels used to generate the electricity sold to those customers in the previous year. Utilities must disclose the information, similar to a content label on a food product, to new customers and post the information on their public websites. The disclosure must show the percentage of electricity by fuel type, such as coal, hydroelectricity, natural gas, nuclear, wind, and solar.
Benton Franklin Trends 5.3.2 Electricity Consumption by Type provides data from the Washington Department of Commerce about the region’s electricity generation profile. Benton County data combines Benton Rural Electric Association, Benton County PUD, and the City of Richland. Franklin County data combines Franklin County PUD #1 and Big Bend Electric Co-Op. Since Big Bend operates in both Adams and Franklin County, adjustments were made to estimate Franklin County’s shares.
This indicator measures the sources of electric power production and as a share of total electricity production in Benton & Franklin Counties combined. The six categories are: Hydroelectric, Nuclear, Renewables, Natural Gas, Nuclear, Renewables and Other (Petroleum, Other Non-Biogenic). Data is provided for both Benton & Franklin as well as for the state.
For the ten years prior to 2019, hydroelectric sources accounted for over 80% of all electricity in the Tri Cities. Since then, hydro’s share has slowly fallen to just over 76% in 2022. The reliance on hydroelectric sources tends to be greater in eastern Washington than the statewide average of 54%. In fact, in Grant County, 98% of all electricity comes from hydro, and in Chelan County, 80%.
One of the unique aspects of electricity generation in the combined counties is the use of nuclear sources. While the share of total electricity coming from nuclear power has been holding steady at around 10% of region’s electricity consumption, this share is more than twice the state average of 4.3%.
Outside of hydro and nuclear, the mix of fuels used to generate electricity continues to change over time. Starting in 2018, in the combined counties, there has been an uptick in petroleum and other non-biogenics, closing in on 9% in 2022 and making it the third highest source in the Tri Cities area. A similar trend has been occurring statewide where petroleum / non-biogenics comprise 13.2% of electricity consumption, on average.
Renewable sources of electricity such as solar, biomass, biogas, biogenic waste, and geothermal have been used increasingly more, from less than 1% 15 years ago to nearly 5% in 2022, its historical peak. This rate is still below the state rate of nearly 10% of all electricity annually.
In terms of fossil fuels, while natural gas saw an increase from 2009 to 2019, it’s share in 2022 of 0.5% is only half of what it was in 2008. Statewide, natural gas sources account for 10% of electricity. Coal also is a major source of electricity statewide at nearly 9%, yet is negligible in the combined counties.
While the Department of Commerce manages the fuel mix program, the Department of Ecology is tasked with using the data to estimate the statewide greenhouse gas emissions from electricity consumption in their overall greenhouse gas inventory for the state. While the heavy reliance on more “clean” sources such as hydro and nuclear are positive for the environment, the increasing share of petroleum and non-biogenics is increasing greenhouse gas emissions in the region.
According to the latest greenhouse gas inventory, in the combined counties, a calculated 211,000 metric tons of carbon dioxide equivalents (MT CO2e) were emitted from fossil fuel generated electricity in 2022. Renewables also contribute to greenhouse gas emissions, though at a smaller rate than fossil fuels. For example, every MWh of fossil fuel generated electricity results in 0.4 MT CO2e, compared to 0.009 MT CO2e / MWh for renewable sources of energy. As a result, 45,000 MT of CO2e was emitted in the combined counties in 2022 due to electricity generated from renewable sources.
While the Tri Cities is fortunate to rely on clean sources such as hydro and nuclear, it is still important to continue to monitor the region’s overall fuel mix profile, especially as the use of fossil fuels and even renewables (non-hydro) can contribute to greenhouse gas emissions and the threat of global warming.