How I kept cool with NYC's free battery program for window AC units

Bonus: Every Electric’s batteries are beloved by household cats.

My family has spent four summers participating in demand response programs whereby utility companies pay customers to reduce energy use on the hottest summer days. Most summers have involved carefully precooling our New York City apartment before switching off the air conditioners and sweating it out during the designated demand response periods.

But this year, we kept our window air conditioners running throughout a heat dome event that drove daytime temperatures into the triple digits and made the nights oppressively hot. The difference was that we powered the air conditioners through two household batteries tucked away unobtrusively in the corners of our living room and bedroom.

We were among about 1,000 New York City households that took part in a free and growing program offered by the local startup Every Electric. The company’s proposition is simple: Get one or more batteries delivered to your home, plug the batteries into a standard wall electrical outlet, and then plug your window air conditioners into the batteries. Households can keep running air conditioners as usual during peak demand periods while also earning money through the local demand response program with the utility company Con Edison.

“Being able to make air conditioners drop off the grid without actually impacting the comfort of residents was really awesome to see,” said Andrew Wang, co-founder and CEO of Every Electric, in an interview with Ars.

Wang and cofounder Richard May first met while working together as postdoctoral researchers at the Columbia Electrochemical Energy Center at Columbia University in New York City. In 2023, they launched the startup under the name Standard Potential Co., with a focus on developing sodium-ion battery chemistry for commercialization.

But they soon pivoted to a very different business plan—deploying residential batteries across New York City households to create a network of energy storage resources acting as a virtual power plant. The company officially rebranded as Every Electric in 2026.

Getting set up

Many companies have established virtual power plant programs to offer utility companies greater flexibility and resources for managing electricity demand on the grid. Every Electric stands out for piloting a free power bank program that loans batteries to apartment renters and other households in exchange for a temporary deposit, which the company has reduced from $50 to $30 per battery.

The deposit is returned when a household decides to send the batteries back. Customers can also purchase the batteries outright for $650 each.

The battery delivery and setup process is straightforward. When the drop-shipped batteries arrived in their boxes, I plugged them into the appropriate wall sockets and followed a simple process to register the battery serial numbers with Every Electric and connect the batteries to my home Wi-Fi network.

Once connected to a local household’s Wi-Fi, the batteries act as power banks that automatically charge during low-demand periods at night and discharge their energy storage when air conditioners are running during peak demand periods. Every Electric automatically manages the battery cycles remotely.

Customers eventually get paid through Every Electric online accounts linked with Con Edison’s Smart Usage Rewards program. Every Electric gets paid directly by Con Edison as a program partner and, in turn, generally promises residents can earn $150 each year per air conditioner.

“There’s a business model innovation here where you make [household batteries] as easy and as accessible as possible, you get them as far and wide as possible, and then you essentially share in the value that you provide in the grid,” Wang told Ars. “We split the earnings so that households can see tangible benefits, and then we pay off the assets and grow the program as it goes along.”

Using the battery

Every Electric’s battery of choice is the Bluetti Elite 200 V2, a lithium iron phosphate battery that can store 2 kilowatt-hours of energy while being compact enough for smaller New York apartments. It’s compatible with any 120V plug-in air conditioner, but it has four standard AC sockets that can also accommodate other appliances such as plug-in fans or air purifiers.

Additional battery sockets can charge laptops, smartphones, and other electronic devices that have power cables using USB-A or USB-C connectors. A 12V DC outlet in the style of a car’s cigarette lighter is also available.

The batteries can even provide backup power during power outages. For example, households can plug their Wi-Fi routers or refrigerators into the batteries to keep those devices running.

One bonus has been the discovery that feline family members of various New York households especially enjoy hanging around the batteries. “We found out cats are big fans of the powerbanks,” Wang told Ars. “I think it’s because they’re a little warmer.”

Despite such upsides, there have been a few kinks to work out during peak demand periods. When the utility company Con Edison had to reduce voltage for hundreds of thousands of customers across New York City to protect grid equipment during extreme heat periods, the power draw from the batteries tripped my apartment unit’s circuit breaker on two separate occasions.

Every Electric’s team responded by continually updating the battery firmware to reduce the risk of tripping local circuit breakers. That challenge can vary depending on each customer’s building.

“Every household is unique, and sometimes you have pre-war buildings with old wiring,” Wang told Ars. “You have to manage both some of the losses that are on the ConEd side and then some of the losses that might be in the wiring in people’s walls to finetune how we operate the power banks to fit within the parameters of each household.”

From dozens to thousands of batteries

The company initially deployed 100 batteries across 65 households in the first test run in the summer of 2025. This year, it scaled up deployment to 2,000 batteries across about 1,000 households, providing the total equivalent of four megawatt-hours of energy storage during the summer of 2026.

“If you picture one of the big utility-scale, containerized batteries, one of those blocks is usually four megawatt-hours,” Wang explained. “So we’ve sort of taken that up and broken it up into 1,000 pieces spread across the city.”

This approach opens the door for distributing residential batteries to many more households by making inroads into the largest US city with more than 2 million rental homes. And more than 80 percent of New York City housing was built more than 50 years ago, meaning that they typically rely on window air conditioners without central air conditioning.

But not every initial customer has been an apartment dweller—early adopters also include residents of single-family homes in the New York City boroughs of Queens and Brooklyn. Some residents have even paired the batteries with plug-in solar panels to make the most of combining household energy storage with renewable power.

Whatever the home configuration, Every Electric’s program has proven popular in its first two years. The wait list grew to requests for more than 15,000 batteries this past summer—and Every Electric is aiming to scale up to more than 10,000 deployed batteries in 2027.

Every Electric remains focused on New York City as its home court. But as the battery network grows, the startup is also exploring new ways for Con Edison and other utility companies to get value from the distributed energy storage system beyond just participating in the demand response program.

“We have new utility territories that are coming to us—they’re seeing that you can drop-ship literal megawatt hours to customers as a solution,” Wang said. “So we’re certainly looking at how to map this model onto new markets.”