The National Renewable Energy Laboratory (NREL) conducted the Interconnections Seam Study to analyze the costs and benefits of optimized nationwide transmission expansion. The study develops four transmission designs with various levels of increased transmission capacity aimed at connecting the nation’s main grid regions. Each design scenario is analyzed under eight scenarios with different assumptions regarding transmission costs, renewable generation levels, wind and solar costs, gas prices, and generator retirements. Between 2024 and 2038, the analysis finds total transmission investment needed ranges from $40 billion under a base scenario to $101 billion under a high variable generation scenario where 39% of annual generation is composed of wind and solar. The study approximates cost-to-benefit ratios over a 35-year period to be as high as 2.9 under the high variable generation scenario. Interconnections Seam Study Share this TweetShare on Twitter Share on LinkedInShare on LinkedIn Share on FacebookShare on Facebook Related PostsACORE’s 2023 Priorities for Transmission Permitting and Siting LegislationFebruary 6, 2023A Roadmap to Diversify the U.S. Renewable Energy and Battery Storage Supply ChainsDecember 15, 2022House Letter to Biden on Commerce InquiryMay 18, 2022Commerce 2012 Scope ClarificationMay 10, 2022Auxin February 8 2022 PetitionMay 10, 2022Commerce March 25 2022 Initiation MemorandumMay 10, 2022
