Power companies say local residents don't need to worry about brownouts or blackouts, even as the Philadelphia region enters its fourth day of temperatures in the mid-90s.

Regional electric and natural gas provider PECO and power grid operator PJM both say they have energy to spare for the scorchers ahead.

That's not the case in New York, where the regional grid operator has urged customers to conserve electricity amid forecasts that energy use Wednesday will be within 500 megawatts of the all-time peak recorded by the New York Independent System Operator.

PJM spokeswoman Paula DuPont-Kidd said PJM is predicting today will mark the peak use for the summer so far, even if it's not historically high.

"It doesn't look like we are going to break any records necessarily today in the Philadelphia area today, but it is going to be a demanding day," she said.

PECO expects today's peak usage won't even make the top 20 of their greatest recorded energy demand loads, which reached an all-time high in July 2011.

As hot as it's been for the past few days, the heat wave hasn't lasted long enough to cause major problems, PECO spokesperson Ben Armstrong said.

"You really need an extended period of hot weather and oppressive weather to push electric usage to record levels," he said. "We've seen several days of 90 degree temperatures, but the forecast is that those temperatures will fall off this weekend and into next week, which will then bring usage down."

But Armstrong cautioned against cranking up the AC just yet.

"We would say keep your thermostats at a constant, comfortable level 74 or 76 degrees or even higher when at home," Armstrong said, explaining a general best practice to conserve energy.

Why then is New York State struggling to handle the load?

The PJM grid is more robust, said Allen Freirfel, senior vice president at Viridity Energy, a company that balances energy load for customers in New York City and Philadelphia.

"In New York, we’ve had hours and hours of load curtailment every day this week," he said. "I think the PJM system, because it’s so much larger, has more flexibility, more reserve, inherently built into it."

The PJM grid, among the largest in the country, covers portions of thirteen states from Michigan and Pennsylvania down to Tennessee and North Carolina.