By Adam Swift
The owners of a proposed Flatiron Energy Energizer Storage battery facility proposed for 284 Eastern Ave. held an informational meeting with the planning Board on proposed changes to its original plan last week.
Flatiron will be back before the planning board on Tuesday, Feb. 24 for the public hearing on the change request for the special permit, which was originally approved in the fall of 2024.
Flatiron Energy is an energy developer, owner, and operator that owns and operates the energy storage systems it develops. The original plan was to construct a two-story building on the property for the energy storage unit.
Now, Flatiron is looking to replace the single, two-story building with about 124 individual modular units on the property.
The company has agreed to a Payment in Lieu of Taxes (PILOT) and community-host agreements for the project with the city.
The property itself is about 3.7 acres and includes Willoughby Street, which will be the main access point to the project.
The property is also adjacent to the Eversource Chelsea electrical substation and Flatiron will be able to tie into the electrical grid.
At last week’s planning board meeting, several board members asked questions about the safety of the new approach, both from a security and fire view.
In addition, Flatiron plans to build a screen along the property with a potential mural.
“Since (October of 2024), Flatiron has contracted with a contractor to build the project, Consigli Construction,” said Flatiron project manager Hunter Prange. “Additionaly, since then, this project was awarded by the Massachusetts Department of Energy procurement for the energy stored, discharged, and charged by this project.”
As part of the original design of the building-based design, there were a series of special permit exemptions that were granted, said Flatiron project developer Erin Baker. That design also had a building height of 40 feet, which was within the height allowed by right in the zoning district.
Baker also noted that the previous use of the lot was for a limousine company, which is no longer in operation.
“So right now, there is just the existing building that is there that will be demoed in any project scenario,” said Baker. “There was a use, there were robust cars and a lot of parking … that has now ceased and he has moved his operation and that is now just a vacant lot and that building.”
The proposed more modular, container-based design is common for battery storage projects across the country, Prange said.
“In terms of resiliency, compared to when it was in a building, all equipment on site will be raised so it is in accordance with the 14-foot base flood elevation,” he said. “This matches up with our 25-year lifetime of the project until 2050, accounting for floods, storm surge, sea level rise, etc.”
The new configuration is also setback from the sewer lines that run through the site, Prange said. Additionally, he said Chelsea Fire Chief John Quatieri is supportive of the design.
“Finally, one of the other main changes from the previous design is the substation which allows us to connect directly to the Eversource substation,” Prange said. “This should limit impact within the MBTA zone of influence, which is up on (the) side of the project.”
The proposed changes will allow the project to come online much earlier and condense the construction timeline, Prange said.
“It will also allow us to adhere to the conditions of the host-community agreement faster and payments will start flowing into the city faster,” he said.
Planning board member Eric Czernizer asked if the modular units were accessed from the inside or the outside.
“To access for maintenance purposes for any reason, there will be a panel on the side to open and access the components,” Prange said. “These are not designed to be walked in at all.”
Board members also raised questions about how the site will be monitored for security purposes.
“The site will be monitored 24/7 from a security standpoint with access to central station monitoring,” said Prange.
In the areas where there is not a screen wall around the property, he said there will be a high fence and there will also be cameras located on site.
Board member Nick Valentine asked about the operation and the end purpose of the stored energy.
“Massachusetts has what they call a clean peak standard, so the ultimate goal for this project and projects like this is to store energy when supply is very high and demand is a little lower,” Prange said.
That energy can then be sent back to the powergrid when there is a higher demand, he said.