Some regional energy decision-makers are making sure there are enough “multivalue” transmission lines for a net-zero future, while others are falling behind or even failing—but all regions need improvement, at least according to advocacy group Americans for a Clean Energy Grid in its recent report, “Transmission Planning And Development Regional Report Card.”

“If a new transmission line is built to connect and deliver low-cost generation from the center of the United States to the East Coast, that line will lower electricity costs for consumers and business, increase reliability for the regions connected by the line, and may help some states and businesses achieve public policy goals,” according to the report.

The inaugural report will serve as a baseline from which future progress can be compared, as there is room for improvement. Very little large-scale regional and interregional transmission is getting built, as construction of new high-voltage lines has fallen steadily over the last decade. The last peak was in 2013, with roughly 4,000 miles of high-capacity lines above 345 kilovolts added to the grid.

“California and the Midwest (MISO) score the highest with efforts just over the last two years to proactively plan for the future resource mix,” the report states. “The Southeast region shows the greatest room for growth, while the West (minus California), mid-Atlantic (PJM), New England (ISO-NE), and Texas are also lagging in their planning and development efforts.”

While aggregate spending has grown significantly from under $5 billion annually 20 years ago to around $25 billion per year now, very little of that is for large, long-distance regional or interregional lines. From 2013 to 2017, roughly half of the approved transmission investments were outside regional planning and cost allocation processes—where the long-distance high-capacity lines are reviewed. In non-RTO regions, no regionally planned line has been approved to date.

In western MISO, some current generator upgrade costs have been more than $750 per kilowatt, roughly double the interconnection costs related to MISO’s MVP projects at $400 per kilowatt.

According to the Department of Energy’s February 2023 “National Transmission Needs Study,” moderate load and high clean energy scenarios required a 57% growth in transmission capacity by 2035 over today’s system. High load and high clean energy scenarios necessitated doubling U.S. transmission capacity by 2040.

All regions must proactively plan for their future needs and provide more information for public review and scrutiny.

“This progress does not strictly depend on compliance with potential new rules from FERC, but on the initiative of the regions and their participants in enhancing their planning processes and building much-needed high-capacity regional transmission,” according to the report.