Can larger batteries safely power residential buildings? A project in New York aims to show how

A battery system installed in a Buffalo, New York, apartment building will store excess energy when it’s plentiful and power the building when the grid is strained and electricity is costly. The manufacturer and state officials hope it will show that larger batteries can safely operate where people live and work.

The 3.75 megawatt-hour lithium-ion battery system, which can power the Peace Bridge Place affordable housing complex for several days, is among the largest battery systems in a U.S. residential building, manufacturer Viridi and developer Good Carbon Co. said Tuesday.

“We want our electric power to be resilient, affordable and available. Distributed battery storage accomplishes all three,” Viridi CEO Jon M. Williams said. “The only thing that has been holding up installations at scale is safety; a lot of the products on the market over the last 10 years have burned things down.”

Deploying large batteries that can safely power apartment buildings is an important step toward replacing fossil fuels with renewables, experts say, but they're uncommon because of the cost and concerns about fire risks. Already, larger batteries are paired with solar and wind projects, and homeowners are using smaller batteries to store excess energy from rooftop solar and for backup power.

Batteries help maintain a steady flow of power when sources such as solar and wind are not producing. They charge when the sun is shining or when wind is blowing. That energy can then be used when demand is high.

Batteries can also store excess electricity from hydropower, and New York is one of the top hydropower-producing states. Buffalo is close to Niagara Falls, where most of the state's hydropower is produced.

When electricity demand is high, Peace Bridge will use the battery. It will get paid by the utility for not drawing from the grid and for sending power back if needed. This helps lower the complex’s overall electricity costs, which benefits residents. The building can use the system during outages, too.

The New York State Energy Research and Development Agency helped fund the Peace Bridge Place project, as part of its focus on including disadvantaged communities in the clean energy transition.

“It goes a long way toward demonstrating the safety and viability of these types of projects,” said NYSERDA President and CEO Doreen Harris.

Viridi has manufacturing facilities in Buffalo and Richmond, California, where a state grant assisted with renovations. California Energy Commission Chair David Hochschild said he's impressed with the company.

More than two-thirds of California's electricity comes from clean energy and batteries get a lot of credit for that, Hochschild said. As electricity demand grows, batteries help ensure the grid is reliable, reduce pollution and contain costs, he added.

“I believe the battery industry is the single most important energy industry for the next several decades,” said Hochschild, who co-founded the Electric Innovation Initiative to use electricity instead of fossil fuels more broadly throughout the U.S. economy.

As large battery fires have garnered attention, some communities have opposed further development. However, the failure rate for batteries has decreased as more are installed, according to the Electric Power Research Institute.

Viridi spent six years and $10 million figuring out how to make a fireproof container for batteries. Half the cost was for batteries Viridi destroyed during testing.

Viridi uses plates, pouches and spacing to isolate each battery cell. If one fails, the energy dissipates instead of spreading to the next battery, so that no gas, smoke, heat or fire escapes the container, Williams said.

Jigar Shah, an expert in clean energy financing and deployment, said the Peace Bridge Place system is a milestone in overcoming safety concerns.

To ensure nothing would catch fire when used inside a residence, Viridi's system had to pass a test where the battery was forced to fail while a cheesecloth covered the container. The cheesecloth did not char or ignite, according to the test report record.

Viridi announced in April it met stringent Underwriters Laboratories safety standards so its system could be installed indoors without adding additional fire suppression to a building.

Shah, who led the Department of Energy’s Loan Programs Office during the Biden administration, said Viridi is the only company to consistently pass this “near impossible” test.

Shah thinks far more U.S. homes will use batteries for backup power by 2030. The U.S. can meet much more electricity demand and avoid costly upgrades to the grid if batteries are strategically deployed, he added.

Viridi and Good Carbon Co. chose the Peace Bridge apartments because the all-electric building uses a geothermal system for heating and cooling rather than natural gas and needed additional, resilient power. The electricity demand locally can exceed the available supply, so the utility National Grid supported the endeavor, Williams added.

Peace Bridge is considered affordable housing because renters earn no more than 80% of the area's median income, Good Carbon said. It said energy storage will be an important part of future multifamily housing projects.

Viridi has been manufacturing in Buffalo since 2018. A medical research building in the city is using its battery system, too. Viridi's plant could build enough battery packs in a year to supply energy for about 14,000 average U.S. homes for 24 hours, Williams said.

Harris, at NYSERDA, said the state needs more options like this for maintaining a reliable grid and managing costs. Gov. Kathy Hochul has made that a priority.

“If we don’t need to build generation, we can utilize the grid that we have more effectively, that’s extremely valuable to us,” she said.

In California, 2,000 battery storage systems are being added each week and the largest in the world is under construction in Fresno County, Hochschild said. He thinks the battery industry is poised to take off.

He said, “We’re just getting started.”

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Peace Bridge Place apartments that have Viridi's lithium-ion battery energy storage system sits in Buffalo, N.Y., Thursday, Oct. 15, 2026. (AP Photo/Lauren Petracca)

Viridi's lithium-ion battery energy storage system is installed in Peace Bridge Place apartments building in Buffalo, N.Y., Thursday, Oct. 15, 2026. (AP Photo/Lauren Petracca)

Paige McNair stacks lithium-ion battery modules inside Viridi's manufacturing plant in Buffalo, N.Y., Thursday, Oct. 15, 2026. (AP Photo/Lauren Petracca)

A worker checks over a lithium-ion battery module inside Viridi's battery system manufacturing plant in Buffalo, N.Y., Thursday, Oct. 15, 2026. (AP Photo/Lauren Petracca)

Battery packs move down an automation line at Viridi's manufacturing plant in Buffalo, N.Y., Thursday, Oct. 15, 2026. (AP Photo/Lauren Petracca)

Employees work inside Viridi's battery system manufacturing plant in Buffalo, N.Y., Thursday, Oct. 15, 2026. (AP Photo/Lauren Petracca)

Viridi's lithium-ion battery energy storage system sits in their manufacturing plant in Buffalo, N.Y., Thursday, Oct. 15, 2026. (AP Photo/Lauren Petracca)

Derek Cheatom, left, a production supervisor, checks a unit for loose wires inside Viridi's battery system manufacturing plant in Buffalo, N.Y., Thursday, Oct. 15, 2026. (AP Photo/Lauren Petracca)

A sign is displayed for Peace Bridge Place apartments that have Viridi's lithium-ion battery energy storage system in Buffalo, N.Y., Thursday, Oct. 15, 2026. (AP Photo/Lauren Petracca)

Nearly a decade after Boeing unveiled its largest 737 Max jet, the company has cleared a major hurdle in its effort to bring the plane to airlines. The Federal Aviation Administration approved the Max 10 for passenger service Tuesday, ending years of delays.

The 737 Max 10’s certification represents another milestone in Boeing’s efforts to restore its reputation and financial footing after years of safety, quality and production challenges. With production approved, the aircraft can now be sold to domestic and foreign carriers.

Transportation Secretary Sean Duffy said the certification followed “extensive safety reviews,” including thousands of hours of test flights, and called it a major win for American manufacturing.

“To think that it took us almost 10 years to get here. We all probably had a little less gray hair 10 years ago," Duffy said during a visit to Boeing's manufacturing plant Tuesday in Everett, Washington.

The Max 10 is an important piece of the company's effort to regain ground in the narrow-body market. For airlines, the larger plane offers a way to carry more passengers on a single flight, potentially lowering costs per seat. For travelers, it could eventually mean more seats on popular routes, though the impact on fares will depend on how airlines deploy the planes and how much competition they face.

Stephanie Pope, president and CEO of Boeing Commercial Airplanes, said during Duffy's visit that the certification "clears the path to deliver an airplane that will set a new standard in commercial aviation." The Max 10 will typically seat 185-210 passengers, according to Boeing, compared with 175-195 on the Max 9 and 160-180 on the Max 8.

“Today is a very, very special day. It caps years of hard work and dedication by many," Pope said. "It marks another major milestone in our recovery, and it unlocks a key to our future growth.”

The company expects to begin deliveries in 2027.

The single-aisle jet was introduced at the Paris air show in 2017 to help Boeing compete with rival Airbus. But technical and regulatory hurdles repeatedly delayed certification.

Boeing’s struggles have been particularly acute since two deadly crashes involving the smaller Max 8 killed 346 people in 2018 and 2019 off the coast of Indonesia and in Ethiopia. In 2024, a panel flew off of an Alaska Airlines Max 9 in midair, renewing scrutiny of Boeing’s manufacturing and safety practices.

The delays have held up a key part of Boeing's business. More than 30 customers worldwide have ordered 1,555 Max 10s that Boeing has yet to deliver, accounting for more than 30% of its total 737 Max backlog.

Major customers include United Airlines, Delta Air Lines, American Airlines and Ryanair. Alaska Airlines joined that list in January, ordering 105 Max 10s, with options for 35 more.

The Max 10 is intended to compete with Airbus’s A321neo model family, which entered service in 2017. The largest A321neo can carry more passengers and fly farther without refueling than the Max 10.

Still, Boeing designed the Max 10 to carry more passengers while burning less fuel than older aircraft — a potentially attractive combination for airlines facing soaring jet fuel costs amid the U.S. war with Iran. Those rising costs have put added pressure on airlines to control expenses.

Certification means the FAA has determined that the Max 10’s design meets safety standards, following engineering reviews and flight testing. But Boeing must continue to show it can consistently build the aircraft to the approved design, and each plane must be cleared before it can fly passengers.

The Max 10’s certification completes the lineup of four 737 Max models. The FAA cleared the Max 7 for airline operations in August.

Pope on Tuesday described the certification of both the Max 7 and Max 10 in the same year as a sign of the company’s resilience.

In the wake of the fatal Max 8 crashes, the FAA overhauled how it certifies Boeing aircraft. But over the past 18 months, the agency has gradually eased some of its restrictions on the company, increasing the limit on how many planes Boeing can produce. In July, the FAA also said Boeing could once again issue airworthiness certificates for its 737 Max and 787 planes at the end of production, allowing the company to take back some responsibility for determining whether finished aircraft are ready to fly.

FILE - The Boeing 737 MAX 10 performs a demonstration flight during the Paris Air Show in Le Bourget, north of Paris, France, June 19, 2023. (AP Photo/Lewis Joly, File)