With sweltering heat and stifling humidity enveloping the region, the organization that manages New England’s electric grid is expecting “exceptionally tight” operating conditions Thursday evening.
ISO New England anticipates homes and businesses in the region to use a lot of power between 4 and 8 p.m. — the period when solar production falls off and people tend to come home from work and crank the air conditioner. The organization expects demand to peak at 25,850 megawatts of power. Last Thursday, by contrast, topped out at about 17,000 megawatts.
ISO New England officials said they expect to have sufficient power supplies to meet this demand, and they are not requesting people in the region to reduce electricity use, but they are encouraging them to do their part and help reduce the stress on the grid.
“Taking a couple of small steps to reduce energy demand can make a really big difference,” said ISO spokeswoman Mary Cate Colapietro.
Here are some things you can do to help now
- Avoid using energy intensive appliances like dishwashers, washers and dryers, electric vehicle chargers and electric stoves or ovens during peak hours
- Decrease the use of your cooling system just a bit (i.e. turn your thermostat up by a degree or two, or use one setting lower on your AC)
- “Pre-cool” your home before 3 p.m. so you can turn down the AC during peak hours
- Close blinds and curtains to block warm sunlight and trap cool air inside
- Make sure all windows and doors are properly closed if the AC is on
- Turn off lights, especially in rooms you’re not using
- Unplug unnecessary appliances like televisions, computers, printers, video game consoles, and microwaves since many draw small amounts of power even when off
I am but one person. Does any of this make a difference?
Actually, yes.
Past efforts to reduce electricity use on really hot days have made a small, but meaningful difference, Colapietro said. She pointed to data from June 20, 2024 as evidence.
On that afternoon, households and businesses across Massachusetts collectively helped lower demand by 375 megawatts, which is about the output of a medium-sized natural gas power plant.
They did this through a utility program that mobilizes wifi-enabled thermostats and home battery systems across the state when demand starts to rise. Those who opt into the program agree to allow their utility to raise the temperature in their house by a few degrees or discharge their battery.
“We do see an impact when those programs are called upon to reduce energy demand,” Colapietro said.
Shaving the peak has other benefits
Beyond relieving some strain on the grid, reducing energy use during high demand periods — known as “peak shaving” — is also good for your wallet and the planet.
During peak hours, some of the oldest and most polluting power plants in region get fired up. These plants also cost a lot to operate, a reality that is ultimately reflected in your monthly power bills.
“Electricity supply costs on peak days can skyrocket to more than 10 times the price of electricity on normal days,” said Jeremy Koo, assistant director of the clean energy program at the Metropolitan Area Planning Council, Greater Boston’s regional planning agency.
What’s more, utilities need to build the grid to accommodate peak periods, even if a lot of those power lines and substations aren’t always needed during the rest of the year.
Shaving the peak keeps wholesale electricity costs down and avoids a lot of expensive infrastructure, Koo said.
In other words, he added, “the cheapest megawatt is the one we don’t need to use.”
This article was originally published on WBUR.org.
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