At its Jan. 9 meeting, the Connecticut Siting Council took a straw poll of its members regarding Petition 1637, a proposal to develop a 4.99-megawatt Battery Energy Storage System (BESS) at 100 Salmon Brook Street in Granby. During the meeting, two members of the council stated that they were inclined to vote to deny the petition, citing serious environmental and public safety concerns. Other council members likewise expressed concerns, but nonetheless voted to instruct council staff to draft a proposed approval of the petition. Thus, based on the results of the poll, it appears the council, despite concerns raised by a number of its members, is poised to approve the project at its next meeting.
It is difficult to imagine a more inappropriate site for a BESS facility. The Salmon Brook site is surrounded by a high-density residential area, is adjacent to a busy retail center and is located on a groundwater aquifer that supplies potable water to a significant portion of Granby.
We are dismayed by the direction the council appears to be taking and hope the council members will deliberate more carefully before making a decision.
We use the word “dismayed” thoughtfully and purposely. The project involves clear, significant public health and safety risks that can be completely and easily avoided with no discernable impact on the state’s goals related to renewable energy and power grid resiliency. The council need only follow a safety guideline it utilized just two months ago to deny similar, but smaller, BESS projects in New London and Waterford.
Thermal Runaways
The public safety concerns revolve primarily around the risk of a “thermal runaway” event. If you are not familiar with that term, conduct a quick internet search. In very short order, you will recognize the magnitude of what can happen if there is a failure at a BESS facility. In short, failures can result in the battery storage containers igniting and exploding, and then burning at temperatures that make it impossible to extinguish or control.
While we recognize that thermal runaway events may be statistically rare, they do happen. The risk of an event occurring cannot be eliminated. It is, frankly, the council’s job to acknowledge this risk and to protect against it.
The International Association of Fire Chiefs (IAFC) has issued guidance regarding responding to a thermal runaway event. In that guidance, the IAFC recommends that first responders establish a “clear zone” of at least 300 feet around the perimeter of the facility. The intent of the clear zone is, obviously, to protect life and property.
In November 2024, the council utilized this IAFC guidance to deny smaller BESS facilities in New London and Waterford because there were property lines within 300 feet of the facilities proposed in those communities. The same circumstance exists at the Salmon Brook site. Not only are there multiple property lines within 300 feet, but there are also at least four buildings containing offices, health care providers, restaurants and retail businesses within that perimeter.
There is simply no reasonable justification for not affording the citizens of Granby the same protections that the council provided in New London and Waterford.
Water Supply Contamination
A thermal runaway event at the Salmon Brook site would also have significant impacts on Granby’s water supply. In addition to establishing a minimum clear zone, current emergency response guidelines call for the application of water to the battery containers for the duration of a thermal runaway event.
KCE CT, LLC (KCE), the proposed developer of the Salmon Brook site, agrees with these guidelines. In its application to the council, KCE stated, “During defensive firefighting efforts, application of high volumes of water from an appropriate distance may be applied to the outside of the container to help cool the unit and prevent further reactions or a fire from developing.” And, according to KCE, a thermal runaway event can last up to 24 hours per container. There are eight containers proposed for the Salmon Brook site.
So, if a thermal runaway event occurs, it is likely that thousands of gallons of water will be applied to battery containers that house substantial amounts of hazardous materials. This water, and the hazardous materials mixed with it, must, under the current design, enter either the groundwater aquifer that supplies most of Granby’s drinking water, or the Salmon Brook/Farmington River tributary system, or both.
We appreciate the challenges the council faces in implementing Connecticut’s energy policies. Carrying out these policies, while at the same time protecting local communities, can be a difficult task.
But, the decision with respect to the Salmon Brook site should be an easy one. The BESS’s purported benefits to the grid system can be provided at any number of other sites located in proximity to the transmission line. KCE specifically acknowledged this during a presentation it made to the Granby Board of Selectmen in August 2024.
Under the state’s regulatory system, the Town of Granby has no authority or ability to protect its citizens. We must rely on the Connecticut Siting Council to do so. With respect to the Salmon Brook site under consideration, we aren’t asking much. We are merely asking the council to: 1) enforce the same safety standards it applied in New London and Waterford; and 2) err on the side of caution to protect public health and safety, especially since the proposed BESS’s benefits can be provided at other, less sensitive, sites.
If, under the current regulatory scheme, this is, in fact, too much to ask, and the council either lacks the authority to reject sites that pose these risks (as the presiding officer seemed to indicate), and/or, the council isn’t obligated to apply consistent safety standards across the state, the system is broken. Seriously broken.