Achieving the ambitious decarbonization goals established by the Biden administration, 100 percent clean electricity by 2035 and a net-zero emissions economy by 2050, requires substantially increasing the share of clean and renewable energy resources in the electricity generation mix. To reach these decarbonization targets cost-effectively, renewable power will need to grow to multiples of current levels. The transmission system is not equipped to handle the anticipated substantial increase in power flows; its lack of capacity and availability leads to grid congestion, which causes higher energy prices and curtails renewables. Moreover, with the anticipated electrification of the economy leading to large increases in future demand, the burden on the power grid is ever increasing. A report from the REPEAT project estimates that to take full advantage of the subsidies offered in the Inflation Reduction Act (IRA), transmission capacity must grow by about 2.3 percent per year, more than double the rate of the past 10 years (Jenkins et al. 2022).