Stanford power system is explained 2/7/2001

After two electricity blackouts in the past three weeks, many Stanford students are probably wondering how Stanford's power system works, especially with California's energy crisis looming in the background. For almost a month now, California has experienced a Stage Three alert — signaling that the state's electricity reserves are at 1.5 percent of total demand or less.

Recently, the Stanford administration has asked Stanford community members to conserve power, so that the on-campus Cardinal Cogeneration Plant, which provides power to Stanford, will be able to sell more power to the rest of the state.

Robert Reid, manager of Stanford's Energy Management Group, declined to comment on how the school's power system works, citing lack of permission from his superior, Assistant Vice Provost for Facilities Chris Christofferson. In fact, Christofferson declined to allow The Daily to interview any of Stanford's power-related employees, saying, "We're about to go into third party negotiations and I'm not interested in any more publicity for Cardinal Cogen. I'm not going to discuss it further."

Cardinal Cogeneration Plant Operations

Cardinal Cogen is a wholly owned subsidiary of GE Power Systems, whose parent company is General Electric. Commissioned in 1987, Cardinal Cogen has a 15-year energy contract to provide power to Stanford that ends in 2002. The contract provides for energy pricing based on how much Northern California's primary electricity service provider, Pacific Gas and Electric, charges to its customers and is linked to state-mandated energy prices. According to Jim Soutton, operations manager at Cardinal Cogen, about 60 percent of the power produced by the plant is sold to Stanford, and the other 40 percent goes to PG&E.

About nine years ago, Stanford sued Cardinal Cogen over how the plant calculated its energy rates for Stanford. The lawsuit was settled in arbitration, according to Stanford General Counsel Debra Zumwalt, who was working in Stanford's legal office at the time. Annually, Cardinal Cogen generates $25 million in sales; overall, GE Power Systems earned $14.5 billion in 2000.

Asked if the current energy crisis will affect upcoming negotiations for the renewal of Stanford's power contract with Cardinal Cogen, Soutton, said that it might, but that it would largely depend on how the state government will be regulating energy prices in the near future.

Soutton added that even after deregulation of California's power system, Stanford's energy rates have only increased nine percent over the last four years. That's because the state government has placed price controls on the prices PG&E can impose on consumers for electricity.

PG&E was forced to sell most of its own power plants three years ago because of deregulation, so it relies on independent energy providers to get its power.

As a result of skyrocketing prices within the last year on electricity that out-of-state providers sells to PG&E and increased electricity demand in California, PG&E has been driven to the brink of bankruptcy.

Amid accusations that independent energy providers are gouging PG&E by increasing maintenance on plants so they will output less power and, hence, command higher prices, Soutton said that Cardinal Cogen is in fact doing the opposite. "With the current situation in the state, we're making every effort to keep the plant running; we're pushing off maintenance, " he said.

Soutton added, "From our perspective, we have the same contract pricing set by regulated prices as the rest of the state, so we could neither conspire nor benefit from [increased maintenance]."

Soutton said that, even though Cardinal Cogen sells only about 40 percent of its output power daily to PG&E, the loss o Cogen saps even more power from PG&E’s reserves, because the university uses PG&E supplies when Cardinal Cogen is down.

How Cardinal Cogen Works

So what does cogeneration actually mean? In addition to generating electricity, Cardinal Cogen also generates steam used by the University. Soutton said that the steam is used for a wide range of purposes, ranging from food preparation at campus cafeterias to the heating of campus pools to the sterilization of medical waste at the Stanford Medical Center.

The core of the plant is a natural-gas-powered turbine driving a 39.2 megawatt generator. Likened to a huge aircraft engine, this turbine provides the bulk of the power generated at the plant.

The excess heat created by the operation of the turbine is sent to boilers to generate steam. Some of the steam is directly sent to campus while the rest is recycled into a steam-powered turbine, which generates an additional 10.7 megawatts.

The plant does pollute the air with nitric oxides and carbon monoxide, but Soutton explained that Cardinal Cogen is actually quite state-of-the-art in this regard. “We have essentially in 1997 reduced our emissions fourfold, and we are now operating at fifty percent below the limit [set by law],” he said.

Overall, the plant occupies 70,000 square feet and employs 27 people. Workers at Cardinal Cogen are unionized and are represented by the Local 715 of the Service Employees International Union, AFL-CIO.

Stanford’s other power facilities

Stanford boiler plant is Stanford's emergency backup power system should power fail. Built in 1957, the plant's core is made up of four 125 psig (pounds per square inch, gauge), 80,000 pounds-per-hour boilers. They can be fired up using natural gas or, in emergencies, fuel oil.

Stanford also has a chilled power plant, constructed in stages starting in 1972 and ending in 1991. The plant chills steam generated by Cardinal Cogen and the Stanford Boiler Plant. The water generated is distributed to the campus for various uses.

The ice plant supplements the chilled power plant. The plant generates ice using three 2,500-ton electric rotary screw chillers. The ice is produced during late at night, then stored during the day. The ice is then "burned" during the day and provides the same service as the chilled power plant, but at lower cost, because it takes advantage of low energy rates in the middle of the night.

Details of Feb. 5 blackout

On Feb. 5, Stanford experienced a power blackout at around 3 p.m. In an e-mail forwarded to Florence Moore residents, Reid explained the technical details behind the power outage. Essentially, PG&E suffered the outage, but, because Cardinal Cogen's system is connected to the PG&E grid, the Cardinal Cogen plant suffered an excess power load.

As a result, Cardinal Cogen was forced to shut down to eliminate that load. When the Cardinal Cogen plant shut down, steam distribution was also impacted. In addition, the chilled power plant and ice plant were rendered inoperational because both Cardinal Cogen and the normal source of backup power, PG&E, had power shut down.

In the months ahead, California Governor Gray Davis will continue to try and resolve this state's energy problems. As Stanford renegotiates its power contract with Cardinal Cogen, Davis' actions will have a great impact on how much Stanford pays for power after the new contract goes into effect in 2003.