By Hudson Sangree

The Sacramento Municipal Utility District (SMUD) said Friday it is canceling a 500-kV transmission line project it was developing in conjunction with the Western Area Power Administration because the project had proven too expensive and was no longer needed.

The Colusa-Sutter Transmission Line Project (CoSu) was intended to increase SMUD’s ability to import hydroelectric power from the Pacific Northwest and export from the Sacramento area. (See WAPA, SMUD Extend Scoping Period for Colusa-Sutter Project.) It would have created a new link between the California-Oregon Transmission Project (COTP) and SMUD and WAPA facilities on the east side of the Sacramento Valley.

“A recent California Energy Commission study makes the case for projects like this that enhance transmission capability to import valuable out-of-state renewable resources for California to meet its 50% renewable energy goals by 2030,” WAPA and SMUD said in a statement in 2017. That study pointed out that a shortage of available transfer capacity on the California-Oregon Intertie would inhibit California’s ability to import additional carbon-free energy from the Northwest.

In a news release Friday, however, SMUD said “it was determined that the project is too costly.”

As planning for the project commenced, federal power marketing agency WAPA said its existing transmission facilities did not have enough capacity to meet SMUD’s increasing need for energy.

SMUD said that the project’s initial phase, meant to evaluate environmental impacts and conduct preliminary engineering, had shown the estimated $245 million price tag had increased by more than $100 million and could end up costing much more.

The utility said its decision to join CAISO’s Western Energy Imbalance Market starting in April “will provide lower-cost access to a broader regional market,” reducing the need for transfers to and from the Pacific Northwest.

SMUD and WAPA have been working on the CoSu project since the utility’s board of directors approved a development agreement in December 2014. The new line would have connected the COTP system in Colusa County with the Central Valley Project system in Sutter County, improving access to renewable energy generated in the Northwest.

Since the project’s inception, the need for it has diminished, SMUD said.

“Since SMUD started planning the project, the development of SMUD’s long-term integrated resource plan has greatly reduced the value and need of the proposed line,” it said. “The IRP analysis indicates SMUD would better focus its resources on the suite of local, regional and in-state renewable and reliability projects, as well as incremental transmission infrastructure.

“Canceling CoSu also reduces pressure on SMUD rates during the early critical phase of IRP implementation,” SMUD added.