Widespread need for air conditioning strains the aging electric grid — and not all parts of the city are equally impacted.
Samantha Maldonado, The City
There’s nothing like luxuriating in the cool respite of an air-conditioned room during a heat wave. But as sweltering temperatures take hold Thursday through Saturday, it’s important to conserve energy.
Con Ed on Thursday reached out to customers with a request to limit energy use between 2 p.m. and 10 p.m. That’s to avoid outages as New Yorkers blast their air conditioners and strain the grid.
Air conditioning is necessary to stay healthy and comfortable during the hottest days. But bumping up the temperature in your apartment a few degrees and holding off on running power-guzzling appliances can help ensure the electric system’s reliability.
“We recommend setting your air conditioner units to 78 degrees or the lowest of the cool settings,” New York City Emergency Management Commissioner Zach Iscol said Thursday.
While the grid’s operator makes sure there’s enough power capacity to meet our needs during the summer’s hottest days, the physical equipment that sends electricity across the city is at greater risk of overheating. If that happens, entire neighborhoods — and maybe the whole city — could experience power outages.
Diana Hernández, an associate professor of sociomedical sciences at Columbia University’s Mailman School of Public Health who studies energy insecurity, pointed out that those who don’t typically worry about the costs of energy could learn something from those who do.
“We all need to be kind of cognizant about our energy use,” Hernández said. “More people need to be as conservative as households that experience economic need.”
How Con Ed’s Networks Work
The heat, along with high demand for electricity, can overtax the equipment in Con Ed’s system, which serves customers in 70 geographical networks.
Patrick McHugh, Con Ed’s senior vice president of electric operations, likened each network to a suspension bridge with 24 suspender cables that’s able to be held with just 22 cables.
But in times of extreme heat, that’s not a lot of leeway. If more than two of those metaphorical cables break during a heat wave, the whole bridge could collapse. That means the whole network — that is, the apartments, hospitals and streetlights contained within it — is at risk of losing power, which could lead to a “mini blackout,” McHugh said.
To avoid a larger breakdown of the network and a more extensive repair process, Con Ed can reduce voltage in certain areas, an ability it has exercised this summer. In the past, Con Ed has shut off full networks. Now, the company can use its smart meters to shut off individual customers — which it has not done yet.
“We have to make a decision whether we’re going to shed customers to save the equipment, or just see what’s going to happen,” McHugh said. “The probability is the equipment’s going to fail, and then customers go off anyway, and it takes longer to get it back.”
Customers might be frustrated if they have their power cut on purpose, while other neighbors and businesses stay online. McHugh said customers will ask, “‘Well, why didn’t you shut off Times Square?’”
The answer is that the glowing billboards and flashing lights of Times Square are on their own network. That means lowering electricity usage there would not affect customers in Harlem, Jackson Heights or anywhere outside of Times Square.
In other words, customers within a network affect other customers in that same network, so when you mind your usage, you’re helping your neighbors and increasing the odds that the power remains on.
Hernández said it makes sense that customers may be resentful towards a utility like Con Ed, especially during the hottest days of the year.
“But we’re in this moment where there’s different things going on. Extreme heat is one component, the longer-standing climate change issues are another,” she said. “At some point, we all have to come together to realize this is a collective issue and we will be part of the solution.”
When and How to Conserve Energy
For the most vulnerable — those reliant on life-saving medical equipment and the elderly, for instance — maintaining steady electricity is essential. Concern about expensive electric bills may deter lower-income households from switching on their air conditioners, which poses a health threat.
“The goal is simply to get people to turn on their ACs first,” said Daniel Chu, an energy planner for the New York City Environmental Justice Alliance. “You really want to prevent heat-related deaths.”
The point during the day where the demand is expected to be highest — and when the grid is at most risk of being strained — is usually late afternoon, around 5 or 6 p.m., according to Con Ed. Lowering electricity use in preparation for and during that window of time can have the biggest impact on keeping the grid stable.
There are several actions individuals can take to alleviate pressure on the grid, said David Klatt, COO of Logical Buildings. His company runs a program called GridRewards, which pays enrolled electric customers to reduce energy use during those certain peak times. Even customers who aren’t enrolled can use the same tips:
- Postpone using your dishwasher, laundry or other electric appliances.
- Before the hours when demand is highest, cool your space by setting your temperature lower than normal, then raise the temperature later.
- Shut off unnecessary lighting.
- Unplug your TV and large appliances — and your electric vehicle, if you have one.
- Raise the temperature on your refrigerator and freezer by a few degrees.
“The idea is that the small actions across tens of thousands of users all operating in unison [result in] a coordinated, precise energy use reduction,” Klatt said. “Every flipping off of a light switch makes a difference.”
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