E3 analyzed regional 2050 decarbonization scenarios for the Pacific Northwest on behalf of NW Natural, a gas distribution business in Oregon and Southwest Washington. Unlike prior studies, E3’s focused on space heating technologies: both how they perform in cold temperatures and affect the costs of serving heating loads. E3 analyzed four scenarios — two maintaining direct use of gas in buildings, and two assuming large-scale building electrification — and found similar 2050 costs among the gas and cold-climate electric heat pump scenarios, and higher costs in the standard electric heat pump scenario. Gas scenarios require three things beyond the decarbonization strategies common to all scenarios: reducing the carbon intensity of natural gas by blending up to 30 percent carbon-neutral renewable natural gas (RNG) and hydrogen; high building energy efficiency; and deeper GHG reductions in non-building sector emissions. Electrification scenarios require rapid consumer adoption of electric heating technologies, especially cold-climate heat pumps, and significant electricity sector investments to address winter peak demand from electric space heating.