Nov. 10--On the heels of a nationwide rise in natural gas costs, California energy authorities are considering a 60 percent increase in the cap on wholesale electricity prices, marking the first time the cap might rise since the state's energy crisis of 2000-01.

But the proposed rise in the cap, from $250 to $400 per megawatt hour, would not take effect until at least next year. And energy officials -- as well as some consumer advocates -- say the effect on consumer electricity prices is likely to be limited.

Most of California's electricity is now purchased through long- term contracts. The price caps only affect power that is purchased on the spot market, estimated at 2 percent to 5 percent of purchases.

"At one point in time, the price cap was the only thing that stood between us and Armageddon," said Mike Florio, staff attorney for The Utility Reform Network, or TURN, a consumer group in San Francisco. "But the price cap is a lot less important than it used to be. If the spot price blips to $400 for a few hours when a plant goes down or a power line goes out, nobody's going to notice."

San Diego Gas & Electric Co. officials declined to discuss the proposal, saying they needed more time to review it.

The proposal to raise the price caps was made yesterday by the Market Surveillance Committee of the Independent System Operator, or ISO, which manages much of the state's power system.

The committee, which consists of academics from such institutions as Stanford and Johns Hopkins universities, recommended raising the cap to reflect the rising price of natural gas.

The present cap was established in 1998, when the price of natural gas in California was $2 to $3 per million British thermal units.

But the spot price for natural gas has skyrocketed to between $10 and $12 per million BTUs, which led the committee to propose raising the cap.

Committee member Jim Bushnell, research director of the University of California Berkeley's Energy Institute, said the committee worried that if gas prices continue to rise, the costs of generating electricity could outstrip the $250 cap.

"There were ongoing concerns that the cap might get caught below generating costs," Bushnell said. "We would run the risk that some generators couldn't operate in our market and would choose to sell their power out of the state."

The price caps played a key role in the state's energy crisis five years ago.

The caps were lifted when the state deregulated the energy market in 2000, which allowed power companies such as Enron to push the price of electricity to as high as $1,400 per megawatt hour. After a wave of blackouts and skyrocketing prices, the caps were restored in 2001, helping quell the market.

Florio, who repeatedly voted for price caps during his tenure on the ISO board between 1997 and 2005, said they were especially crucial during the energy crisis because the state was purchasing most of its electricity on the spot market.

Since then, he said, the caps have become less important because the state buys most of its power through long-term contracts.

Bushnell added that there is much more competition on the market these days, which should work to keep prices low.

Before the plan to raise the cap takes effect, it must be approved by the ISO board, which probably will not take place until mid-December, ISO spokesman Gregg Fishman said. After that, the plan must go to the Federal Energy Regulatory Commission in Washington.