The US Department of Energy recently released its National Transmission Needs Study, which serves as DOE’s triennial state of the grid report.
The US Department of Energy recently released its National Transmission Needs Study, which serves as DOE’s triennial state of the grid report and is a robust assessment of current and near-term future transmission needs through 2040. The Needs Study is not intended to displace existing transmission planning processes and is not intended to identify specific transmission solutions to address identified needs, but it does identify key national needs that can inform investments and planning decisions.
- There is a pressing need for additional electric transmission infrastructure in nearly all regions of the country to improve reliability and resilience, address high energy costs, and reduce congestion and constraints.
- Increasing interregional transmission — that is, the ability to move power across regions of the country —is needed to move electricity from where it is available to where it is needed, and results in the largest benefits to customers in reducing congestion and constraints. Historically, the data assessed show a need for transmission to alleviate transmission constraints that prevent moving electricity across the interconnection seams —between the Mountain and Plains regions and between Texas and all its neighbors.
- Needs will shift over time as the clean energy transition, evolving regional demand, and increasingly extreme weather events must all be accommodated by the future power grid. By 2030, large relative deployments of interregional transfer capacity are needed between the Delta and Plains, Midwest and Plains, and Mid-Atlantic and Midwest regions to meet future demands of the power grid. By 2040, there is a significant need for new interregional transmission between nearly all regions.
- Improve reliability and resilience. Reliability risks are anticipated to arise in the near-term due to electricity demand growth, thermal generator retirements, and increases in intermittent and limited-duration resource interconnection requests. Additional transmission additions and upgrades in the near-term would help maintain resource adequacy and accommodate generation loss. Additionally, stronger transmission ties with neighboring regions would help support the reliability and resilience of the Mid-Atlantic system during extreme weather events, such as the recent 2018 bomb cyclone and 2020 Winter Storm Elliott events.
- Alleviate transfer capacity limits between the Mid-Atlantic region and New York. High congestion value of interregional transmission from 2012–2020 exists between the Mid-Atlantic region and New York, with an average marginal value of transmission equal to $18/MWh. A high congestion value indicates that additional transmission between the regions would reduce system congestion and constraints.
- Deliver cost-effective generation to meet demand. High-priced areas persist in eastern Maryland, eastern Virginia, and both Maryland and Delaware portions of the Delmarva Peninsula; additional transmission to bring cost-effective generation to demand would help reduce these prices.
- Meet future generation and demand with additional interregional transfer capacity. It is anticipated that the Mid-Atlantic region will need between 28 and 51.7 GW of additional transfer capacity with the Midwest in 2035 (median of 33.8 GW, a 156% increase relative to the 2020 system) to meet moderate load growth and high clean energy growth future scenarios. Smaller additional transfer capacity between the Mid-Atlantic and the Southeast (median value of 6.9 GW) and New York (median value of 2.4 GW) may also be required.