Los Angeles natural gas plant has been leaking methane for years

LOS ANGELES, Aug 26 (Reuters) - A Los Angeles-area natural gas plant has been leaking large amounts of planet-warming gas methane for years, and the city has been aware of the urgency since at least March but has not scheduled repairs until later this year, according to a recording made public on Wednesday.

Faulty natural gas compressors at the 690-megawatt Valley Generating Station have been leaking more than 10,000 cubic feet of methane per hour “for the last couple years,” Norm Cahill, the Los Angeles Department of Water and Power’s director of power supply operations, told the utility’s board of commissioners on Tuesday.

Video of the meeting was posted online on Wednesday.

A leak of that magnitude, over the course of a year, is roughly equivalent to the emissions of 30,000 cars, according to environmental group Sierra Club.

The leak adds to mounting evidence that accidental releases of natural gas from energy infrastructure is a significant contributor to global climate change.

The incident is the latest setback to California’s efforts to slash methane emissions as part of its aggressive push to tackle climate change. In 2015, there was a massive four-month-long leak at an underground natural gas storage facility just a few miles from the Valley Generating Station.

Officials from LADWP were not immediately available for comment. The South Coast Air Quality Management District, which monitors air quality, also did not immediately respond.

Scientists say identifying methane sources is crucial to making the drastic emissions cuts needed to avoid the worst impacts of global warming. Methane, while colorless and odorless, is 80 times more potent than carbon dioxide during its first 20 years in the atmosphere.

The leak was reported to the utility on Friday by NASA’s Jet Propulsion Laboratory, which uses airborne sensors to observe methane sources.

But the utility had been made aware of the extent of leak months earlier, in March, following a study by power industry research group the Electric Power Research Institute, Cahill said.

The utility has struggled to make repairs due to the challenges of taking a large plant offline, he said. New equipment is scheduled to be installed in November. (Reporting by Nichola Groom; Editing by David Gregorio)