NORTH TROY – Operators Friday marked the opening of a new utility-scale battery designed to help the region’s renewable energy projects run more reliably while reducing strain on the power grid during peak usage times.
Sixteen white blocks, about the size of shipping containers, hummed quietly Friday as members of the Vermont Electric Cooperative, the U.S. Department of Energy and other partners announced the completion of the project. It is expected to come online in the next few weeks, after a years-long process that began in 2021.
The 3-megawatt battery can store enough energy to power 600 homes for an entire day, according to Kristin Carlson, a spokeswoman for Green Mountain Power, which will own and operate the project with Vermont Electric Cooperative.
The battery is located in “a really unique place on the grid,” the so-called Sheffield-Highgate export interface, where sometimes “more renewable energy is produced than we can use locally or export via transmission lines,” says Rebecca Towne, executive director of the Vermont Electric Cooperative.
What then happens, she says, is that local renewable energy projects like Kingdom Community Wind — a controversial project in the Lowell Mountains that was completed in 2012 — have to reduce their output or reduce the amount of energy they generate. Essentially, a lack of capacity can lead to renewables being taken off the grid.
The new battery changes the equation and keeps the energy stored until it is needed.
“It’s indicative of a problem we expect to see in the power grid, not just in other places in Vermont, but across the country,” Towne said. “So finding solutions that address this problem is critical as we transition to our energy future.”
When utilities don’t use the battery to keep local renewables running or use the energy stored there to handle peak demand, Green Mountain Power plans to make the stored electricity available to regional grid operator ISO New England, which will use it to “balance the grid on a regular basis,” Towne said.
Operators expect the battery to be fully operational in the next few weeks, with a test run already completed during the July heatwave, when energy demand was at its highest level yet this year, Towne said.
“We were able to test it in real-world conditions and learn a lot from it, which was great,” she said. “And we also found that, as is often the case with complex projects, there are still some things that need to be optimized and improved, and the team has been working on that ever since.”
The Department of Energy provided two million dollars for the approximately five million dollar project; Vermont Electric Cooperative and Green Mountain Power will share the remaining costs.
The battery was manufactured by EVLO Energy Storage, a Montreal-based company and subsidiary of Hydro-Quebec. The batteries contain several redundant safety features, including smoke detectors and hydrogen sensors.
“In an emergency, if there’s gas or fire or whatever, traps open, and even if there’s no power, the system cools just by air and natural convection,” said Vincent David, vice president of deployment and operations at EVLO. “We don’t need to circulate fluid to cool the system. It vents naturally, so the system can be cooled without power.”
Large-scale batteries are becoming more common in Vermont. Green Mountain Power has already installed six large-scale batteries in Georgia, Springfield, Bethel, Middlebury, Bristol and Barre. Together with the batteries installed in customers’ homes, the utility has a total of 68.5 megawatts of battery storage across the state.
As the United States races to combat climate change, federal, state, and local governments are working to increase the use of renewable energy sources and reduce dependence on fossil fuels.
When people burn, produce and transport fossil fuels, pollutants like carbon dioxide and methane enter the atmosphere and trap heat from the sun, warming the ocean and atmosphere and creating more extreme weather like floods and heat waves in Vermont.
In Vermont, lawmakers recently passed an update to the state’s renewable energy standard that increases the amount of renewable energy local utilities must purchase over time.
But in a state where it’s cloudy and snowy year-round, deploying more renewable energy can be difficult. Utilities and renewable energy advocates see battery storage as a key way to increase Vermont’s reliance on renewable energy.
“When it comes to expanding renewable energy in Vermont, storage is critical because we need to be able to provide reliable power to customers 24/7,” Carlson said.
Vermont Electric Cooperative owns another 1-megawatt battery in Hinesburg and, according to Towne, plans to implement another major project in South Hero, the details of which have not yet been fully decided.
Imre Gyuk, chief scientist for energy storage research at the Department of Energy, said he worked with Green Mountain Power several years ago to develop a groundbreaking battery storage system in Vermont.
“Vermont is now becoming famous for this,” he said. Because the project is designed to keep local renewable energy running consistently, “this is another project that is essentially the first of its kind.”
