Plans by the city of Los Angeles to develop an 845 MW natural gas-fired power plant to replace a coal generation unit in Utah are facing increasing public opposition.

The $865 million project has the support of Los Angeles Mayor Eric Garcetti, who also is championing a move by the city to 100% dependence on renewable energy.

Part of the proposal to close Intermountain Power Plant (IPP) in Delta UT, calls for developing a compressed-air energy storage facility on an adjacent site over a naturally occurring salt dome to store output from alternative fuels. In addition, a 488-mile transmission line from Utah to California would be used to carry solar and wind power supplies.

A Garcetti spokesperson has called the transmission line one of the city's "most indispensable" assets for maximizing future access to low-carbon energy sources. The Los Angeles Department of Water and Power (LADWP), the nation's largest municipal utility, also has a similar high-voltage line stretching from the Pacific Northwest that brings in hydroelectric supplies.

With the planned closure in 2025 of the Intermountain coal-fired plant, LADWP would have no coal-fired generation in its portfolio and would have fewer gas-fired plants because of planned closures of several Los Angeles Basin facilities that use sea water cooling.

Environmental groups and community activist organizations have been pressuring investor-owned utilities and elected officials to support California's far-reaching fossil fuel mitigation goals, and have urged the LADWP oversight board to reconsider the IPP gas conversion plans.

LADWP general manager Marty Adams has countered the groups' opposition by noting that replacing the IPP would ultimately lead to more renewable energy supplies. The utility's plans to transition to gas from coal in Utah were outlined in 2014. Last year the oversight board scaled back those plans in the face of growing criticism from environmental groups.