Sweltering heat continued Friday, moving from the Ohio Valley to the East Coast and straining regional power grids.
As temperatures head into near record-breaking territory, demand for power is also getting close to capacity, but authorities in New England say they don't expect to top the record usage set in the summer of 2006. And they're confident they can continue to meet demand.
It's as sure as spring turning to summer. Every time temperatures soar past 90 degrees, fans and conditioners fly off store shelves.
And if you add up all of the cooling power being used this week by countless residents in the region, it could amount to trouble.
"The utility operators are sweating bullets right now. Not because it's hot — they're sweating but because they're concerned about possibilities of failures," says MIT professor James Kirtley.
He says old infrastructure — especially around the Northeast — is prone to breakdowns and overloads. And he says distributing power in this kind of heat can pose extra challenges.
"Because materials expand when it gets warm, that means the transmission line is going to sag, and when a transmission line contacts a tree, you have to shut it down," he says.
ISO New England, the region's electric system operator, is watching for trouble spots and making sure the energy grid keeps humming.
Officials say they have enough backup sources to ensure supply. But just in case, utilities are also working on new ways to try to ratchet down demand.
"When the utilities have called on all of their resources, and there's nothing else left, they are going to press the panic button. And that's where EnerNOC comes in, and we'll make the electricity usage disappear," says Tim Healy, who works for EnerNOC, a company that's been offering utility operators a relatively new kind of insurance policy.
When demand starts to peak, EnerNOC signals thousands of large-scale businesses to dial down their usage.
The company has cut deals with hotels, libraries, and manufacturers — like Okay Industries in New Britain, Conn., where Ed Tremblay is the maintenance supervisor.
"We can shut down a couple of blowers, a couple of electric ovens and we will then, in certain areas, let the air conditioning go up to 80, 82 degrees," he says. "And unfortunately for employees here, that's where it becomes a little more difficult."
On the upside, companies get paid for their reductions, and they get credit for making the sacrifice so individual consumers don't have to.
"Asking consumers to voluntarily conserve is one of the last steps we take," says Marcia Blomberg, a spokeswoman for ISO New England.
Which is no surprise. Heat waves have a way of making people cranky at the very suggestion.
"No, thank you," says Rich Grant, who was sweating outside of a Home Depot. "If you like the heat, go outside."
Arthur Patvee agrees. "This is America. We live in comfortable country," he says while piling a new air conditioning unit into his car. "So this is what it is."
Utility companies say the peak demand will be manageable during this heat wave, as long as it stays just a little shy of peak capacity.