That's the assessment of the Mid-America Interconnected Network, known as MAIN, a consortium of 12 investor- and publicly owned electric-generating companies, including AmerenUE, AmerenCIPS and Dynegy Inc.

The only thing that could change the prediction, said Jackie Olson, a spokeswoman for MAIN, would be for several power plants to be out of operation at the same time or for major transmission lines to stop working.

"In Missouri and Southern Illinois, we may have to cut short-term power contracts because the transmission lines are inadequate," said Olson, adding that such a move will not be obvious to customers.

"We have a reserve margin of 15 percent, which is comfortable," Olson said. "We are forecasting a peak demand of 57,031 megawatts (on the hottest days of summer). That's 2.4 percent higher than last year, which is typical. Growth in demand is 2 to 3 percent a year."

With skillful management, day-to-day demand can be cut to 53,748 megawatts, the network said in its semi-annual assessment to the North American Electric Reliability Council, a private national group.

Utilities in the network buy and sell power to one another as well as outside their areas. The network forecasts net imports of 177 megawatts.

The companies in the network have a combined generating capacity of 62,073 megawatts, Olson said.

Martin Cohen, executive director of the Citizens Utility Board, the consumer watchdog in Illinois, said an early hot spell is no cause for concern.

"We'll be close to 100 (degrees Fahrenheit) in a couple of months," Cohen said. "It'll be OK as long as the utilities aren't caught with their plants down."

Olson said the network's power producers have added 4,913 megawatts of generating capacity since last summer.

Ameren Corp., the parent of AmerenUE and AmerenCIPS, said in its annual report that it expects to buy an additional 500 megawatts of power for the summer. Last year, Ameren added 820 megawatts of combustion turbine generating capacity, plus 692 megawatts in 2000, bringing its total generating capacity to 12,600 megawatts.

The Mid-America Interconnected Network includes Illinois, the northeastern quarter of Missouri, eastern Wisconsin, Michigan's Upper Peninsula, and parts of Iowa and Minnesota.

Power producers in the network keep in close touch to ensure they can meet demand anywhere in the system. They watch the operating condition of the power plants and the transmission lines, which tie the network together.

Under state law, the utilities are expected to have enough generating capacity to meet demand or to be able to buy the electricity they need from other utilities or independent generating companies.

Large commercial and industrial customers may have contracts with utilities or electricity suppliers that can be interrupted when shortages occur.

Interruptable contracts mean that the electricity supplier can cut the power under certain conditions. The customer, a big factory or commercial enterprise, pays a lower rate because it has agreed to accept the risk of interrupted service.

That is what happened in 1998, when a long hot spell in June forced the spot prices of electricity to $4,000 a megawatt hour when such prices usually fell between $30 and $50. Buying outside power during the heat wave cost shareholders of Illinova Corp., the parent of Illinois Power, about $120 million. Much of that cost was incurred because Illinova's nuclear plant at Clinton was off-line.

Even if the wholesale costs of power shoot up, residents and most customers in Missouri will not see their bills rise immediately. In some cases, utilities may try to have those costs factored into future rates.

In Missouri, retail electricity prices remain regulated by the state Public Service Commission. In Illinois, which is undergoing deregulation, residential customers are to begin having the choice of electricity suppliers May 1, when a freeze on residential electric rates is due to expire.

However, state Rep. Phil Novak, D-Bradley, has introduced a bill to extend the freeze on residential rates through Dec. 31, 2006. If passed, it would amend Illinois' Electric Utility Deregulation Act.

Novak contends that Illinois Power consumers would save $174 million if his bill becomes law, while Commonwealth Edison customers in northern Illinois could save nearly $1 billion.

Novak said there is not yet enough competition among suppliers to residential users to hold prices down. He also said he was worried that Illinois could experience a deregulatory "debacle," as happened in California.