The System Value of Grid-Enhancing Technologies under Alternative Transmission Deployment Strategies

Christopher R. Knittel, Juan Ramon L. Senga, and Chaitanya Vuppanapalli

September 2026

Grid-enhancing technologies (GETs) can increase the effective capacity of existing transmission infrastructure, but their system value depends on where they are deployed. Here we use the GenX capacity-expansion model to examine how alternative transmission-targeting strategies affect the value of GETs in a 2035 representation of the US electricity system. We compare economic-based selection using the marginal value of transmission capacity, congestion-frequency-based selection, congestion-weighted random selection, and uniform-random selection. GET deployment is varied from 0 to 100% of eligible transmission lines, with capacity increases of 5–30% on selected lines. Although economic- and congestion-based strategies identify substantially different transmission corridors at low deployment levels, their system-wide cost impacts are similar, with GETs reducing annual system costs by up to approximately $1.34 billion. Congestion-frequency-based deployment can achieve a given system-wide capacity increase by modifying fewer transmission lines, while also producing distinct changes in generation and emissions depending on the corridors selected. At 10% deployment with a 30% capacity increase, for example, congestion-based deployment reduces annual system costs by approximately $25 million relative to the no-GETs case, while producing CO2 emissions nearly identical to those under full deployment. These results show that the value of GETs depends not only on the amount of additional transmission capacity but also on how deployment is targeted, highlighting the potential for strategically deployed GETs to complement conventional transmission expansion where new infrastructure faces long development times.