Transmission is an essential component of a least-cost energy mix, and state regulators at public utility commissions (PUCs) in the United States have a critical role to play in optimizing transmission buildout to lower costs for ratepayers. But transmission is a complicated landscape, with the state regulator’s role appearing during multiple stages of a transmission project’s “life cycle” (see Exhibit below).

In this report, we identify the role of the state regulator across the transmission life cycle and provide recommendations for regulators looking to take action to promote optimal, cost-effective transmission buildout.