Photos from the Vault

Below the Morro Bay Power Plant

On Nov. 4, 2013, California Valley Solar Ranch announced its Carrizo Plain solar electric power plant was finished and operational.

The 250-megawatt facility in California Valley feeds the grid via a transmission line that continues to Morro Bay.

Topaz Solar Farms nearby is expected to be complete next year with a 550-megawatt contribution.

At the other end of the transmission cable is a gas-fired power plant nearing the end of the line.

Four days after the solar announcement, Dynegy announced plans to retire the 1,002-megawatt Morro Bay Power Plant.

Pacific Gas & Electric built it during California’s booming growth of the early 1950s. Now the plant’s antiquated 60-year-old technology is not economically competitive, and it's difficult to obtain environmental permits to operate.

If the Morro Bay Power Plant is demolished, the job could be tougher than it looks. The 450-foot-tall smokestacks are attached to 68 feet of concrete buried below ground.

The Telegram-Tribune reported on construction of the plant in a front-page story (here with typos corrected) published May 15, 1954:

Morro Bay Power Stack Starts Deep in Ground

MORRO BAY, May 15.—Limited operation of Morro Bay’s huge Pacific Gas and Electric company steam power plant is scheduled to begin next March, according to R.B. Owens, project superintendent for Bechtel corporation.

The first of two turbine generators is planned to be ready and in place by that time. A second and similar-sized turbine will be erected by Bechtel and in use one year later (March 1956), Owens said.

Pile Driving

A total of 289 piles are currently being driven 68 feet into the ground, opposite the main structure’s western end, in preparation for the construction of a 450-foot smokestack.

Nearly approaching the height of Morro Rock, the stack will be constructed of concrete with acid-proof brick lining. Work on building the stack is scheduled to begin June 21 and be completed by Dec. 1.

Raymond Concrete Pile Co. of Los Angeles is driving and average of 10 piles a day. It is the same firm concerned with a recent gallery-attracting operation in San Francisco’s financial district. Pile-driving noise had filled the bay city’s Montgomery Street section for many months while anchoring piles were driven for a large insurance company’s new office building. A spontaneous celebration was staged when the operation was recently completed.

The hollow corrugated pile tubing is capped at the base; sections are welded together to form one single 68-foot shell driven into the sandy soil and filled with concrete.

Intake Pipe

Four intake concrete pipes, 54 inches in diameter, are being installed this week in the main structure’s basement. Seawater will be drawn from Morro Bay, adjacent to the San Luis Obispo County dock, for cooling purposes once the plant is in operation.

Owens said no ill effect to the water will be caused and practically all will be returned to the ocean on the northern side of Morro Rock through a 3,100-foot discharge tunnel now under construction.

The power house and boiler section, which comprised the main power plant structure, is constructed on a “floating mat foundation,” according to the project superintendent. The base floor mat is five-foot-thick concrete at its thinnest point, and heavy concrete foundation walls protect the plant from eight feet of surrounding seawater.

High in the mountain of structural steel, the much-publicized 121-ton boiler drum was hoisted and put in place recently. Bigge Drayage company of Oakland took three days to move the 242,000-pound drum from a railroad siding at Camp San Luis Obispo to the Morro Bay site. It now rests 130 feet above the ground.

A series of sand dikes have been created between the huge plant and ocean on the north where four 168,000-barrel fuel tanks will be erected. Work is scheduled to begin next month on the steel containers, each of which will be surrounded by sand dikes. Ice plants have been planted on the dikes to prevent erosion.

An offshore tanker anchorage will be about 4,400 feet offshore with subterranean feeder lines connecting it with the PG&E plant.

Bechtel corporation plans to install a permanent 60-ton overhead crane in the power building. The big hoist will have a 120-foot span. It will be used to install heavy power house equipment and later maintenance operations.

With a weekly payroll approaching $45,000 (this includes sub-contractors’ personnel), Bechtel corporation is adding much to Morro Bay’s income. A total of 438 men and women are currently working on the power plant and according to superintendent Owens the figure may soon rise to about 700.

The plant spokesman was correct that the water would not be harmed by passing through the plant; however, microscopic fish and crab larvae in the water were cooked, causing California to recently issue new rules limiting the amount of ocean water used for operation.

Though the plant built large oil storage tanks, natural gas proved to be the most economical fossil fuel.