Dive Brief:
- The Southwest Power Pool board of directors on Wednesday approved an $8.6 billion slate of 50 transmission projects across its 14-state footprint. The projects are intended to help the grid operator meet peak demand, which it expects will double, to reach 109 GW, in the next 10 years.
- Key to the 2025 Integrated Transmission Plan is development of a 765-kV regional transmission “backbone” that can carry four times the power SPP’s existing 345-kV lines do, and do so more efficiently. The grid operator’s transmission system “is at capacity and forecasted load growth will only exacerbate the existing strain,” it said. “Simply adding new generation will not resolve the challenges.”
- 765-kV transmission lines are the highest operating voltages in the U.S. but are new in both SPP and in the neighboring Electric Reliability Council of Texas market. Texas regulators approved the higher voltage lines for the first time in April.
Dive Insight:
Transmission developers in SPP and ERCOT are turning to 765-kV projects to mitigate line losses and move greater volumes of power into demand centers at a time when electricity demand is expected to rise significantly.
“With the new load being integrated into the system, SPP could see an increase in the footprint’s annual energy consumption by as much as 136%,” the grid operator said in its ITP. “Investments in transmission are the key to keep costs low, maintain reliability, and power economic growth.”
Even under conservative assumptions, SPP forecasts a 35% increase in demand, “making timely transmission investment essential,” the grid operator said.
SPP selected Xcel Energy in February to construct the first 765-kV lines in its footprint. Those lines were identified in its 2024 plan. AEP Texas will build one of the first 765-kV lines in the Lone Star state.
The transmission plan approved by SPP’s board includes 949 miles of new 765-kV lines and 62 miles of new 345-kV lines. The 50 projects were selected out of a larger $18 billion portfolio of projects.
“This portfolio ensures we have the infrastructure in place to support new generation, meet accelerating demand, and enable economic growth while maintaining the reliability our region depends on,” Casey Cathey, SPP vice president of engineering, said in a statement.
The portfolio “supports the interconnection of new generation resources which are critical to maintaining reliability as demand grows,” SPP said. “This includes many dispatchable resources such as natural gas units queued in SPP’s generator interconnection study process.”
Without utilizing 765-kV projects, meeting demand could require “up to six times more infrastructure and up to nearly five times the land,” the grid operator said in a fact sheet about its transmission plan.
High-voltage transmission “delivers significant consumer savings” and “offers a cost-effective way to ease ratepayer burdens at a time of rising electricity rates,” Americans for a Clean Energy Grid said in a July report. 765-kV lines “can deliver power at up to 75% lower cost per MW than lower-voltage alternatives like 230 kV.”
