Oregon Department of Energy blog post about transmission in Oregon and the region. Selected excerpt: 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)."