Potrero plant could shut down this year

State power regulators told Mayor Gavin Newsom in a letter that the Potrero Power Plant will be allowed to shut down after wiring projects have been completed by Pacific Gas & Electric Corp.

The underground wiring projects, which will improve electricity transmission in San Francisco to help protect against blackouts, are expected to be completed by November, according to company spokesman Joe Molica.

The plant will only be allowed to shut down if a new 400 megawatt power cable has been installed between Pittsburg and San Francisco, the California Independent Systems Operator Corporation told Newsom in the letter.

That cable, the Trans Bay Cable, could be switched on within a month, according to project spokesman PJ Johnston.

Under a settlement agreement secured by City Attorney Dennis Herrera, Mirant Corp. must shut down the power plant once it is allowed to do so by the power regulator.