Electricity on the Move: Transmission in Oregon

Electricity supply chain

Oregonians – and beyond – count on a network of transmission lines to move high-voltage electricity across long distances to power our homes and businesses. The lines connect electricity customers to resources that generate electricity, which are often located far away from communities. For example, Oregon’s coastal towns are often powered by facilities east of the Coastal and Cascade mountain ranges.

In the Oregon Department of Energy’s 2020 Biennial Energy Report, our Energy 101 on Electricity Transmission shares the basics about the transmission system, Pacific Northwest trends, how new transmission lines are planned and built, and more.

Electricity travels long distances most effectively and efficiently at high voltages. Generators produce electricity, then “step-up transformers” increase the voltage of electricity to travel along high-voltage transmission lines. Then, to decrease the voltage back down so customers can use it, the electricity passes through “step-down transformers” to distribution lines, which carry lower voltage electricity shorter, “last mile,” distances to customers.

Connecting energy generating facilities to end-use customers requires a lot of transmission infrastructure – thousands of miles in Oregon and across the Pacific Northwest, and over 360,000 miles nationwide. The largest owner of transmission lines in the Pacific Northwest is the Bonneville Power Administration, a federal power marketing administration. Other large owners of transmission lines in the region include: Avista, Idaho Power, PacifiCorp, Portland General Electric, and Puget Sound Energy. Many additional entities across the Pacific Northwest own smaller amounts of transmission lines, including Oregon consumer-owned utilities (like Peoples Utility Districts, co-ops, and municipalities).

Technology advancements and energy policies are driving – and will continue to drive – changes to the transmission system, including: advancements and falling costs of renewable and storage technologies, customer- and policy-driven clean energy goals and requirements, and increased electrification of energy uses that have traditionally been met by non-electric energy supplies (such as electric vehicles).

Transmission Lines in the Western Electricity Coordinating Council

Dive into the full Electricity Transmission 101 online to learn more. Interested in learning even more about electricity in Oregon? Check out these other highlights from our 2020 Biennial Energy Report: