ESCONDIDO, Calif. -- The baker of several brands of widely-available bread has filed a formal complaint charging the San Diego Gas and Electric Company with operating an electric-generating station that showers an industrial park with excess humidity and airborne mold that ruined its product, it was reported Saturday.

Bimbo Bakeries USA filed a complaint with the California Energy Commission, saying it had to install expensive air filters and throw out thousands of loaves of bread in order to control the problem, a local newspaper said.

The commercial bakery bakes 4.2 million rolls and loaves every month for distribution across California, Arizona and Nevada from its bakery on Aldergrove Avenue in Escondido.

Bimbo's brands include Orowheat, Thomas' and Entenmann's, as well as its namesake Bimbo, a popular white sandwich-style bread brand from Mexico.

Bimbo's complaint said the mold problems began when San Diego Gas and Electric opened a new natural gas-fired power plant next to its bakery last year.

The plant has a cooling tower that discharges 2 million gallons of water as steam into the atmosphere every day next door to the bakery.

Bimbo said that grocers began returning moldy bread in increased numbers shortly after the power plant started up a year ago.

"We think there's a link,'' company spokesman David Marguiles told the newspaper.

He said the bakery fixed the problem at its own expense by adding mold retardant chemicals to the bread, and filtering the air intakes at the bakery.

The complaint also said the hot, moist air from the power plant caused a large patch of mold to sprout on the bakery's roof, the newspaper reported.

A bakery manager said he took pictures of the cooling towers coated with mold, which was pressure-washed off by utility employees.

A SDG&E spokesman told the newspaper that Bimbo had never contacted the utility about the issue.

The hot, humid air that is released into the atmosphere is a byproduct of the use of natural gas boilers to generate electricity.

The complaint, a state official said, caused regulators to delay approval for SDG&E to install a new $10 million air intake chiller that the utility wanted to install this summer, to improve efficiency.

The Energy Commission said it plans to send investigators to Escondido next month.

Bimbo's complaint stressed that the moldy bread issue was solved last summer.