Kearsarge's Battery Storage Portfolio Hits 104 MWH Since 2019

Kearsarge Energy will commission four new battery storage projects totalling 70 MWH in 2026, extending a portfolio that has grown to 104 MWH since the company built National Grid's first solar-plus-storage system in Amesbury, Massachusetts in 2019. The company plans a further 200 MWH of construction in 2027. Kearsarge owns and operates its entire storage portfolio directly rather than developing projects for third-party ownership, working across Massachusetts and Vermont with municipal light departments, public power authorities and private landowners.

 

Why Landfills and Underutilised Land Solve Two Problems at Once

 

A recurring pattern across Kearsarge's project history is siting solar-plus-storage facilities on landfills, decommissioned waste sites and other underutilised municipal or private land, including projects at Amesbury's Titcomb Pit Landfill, Haverhill's former Superfund site, Kingston's landfill after decommissioning an abandoned wind turbine, and Concord's Walden Street landfill. That siting strategy addresses two distinct constraints simultaneously: it avoids the land acquisition costs and community opposition that greenfield solar development often faces, while converting sites that typically carry ongoing environmental monitoring or remediation obligations into revenue-generating clean energy infrastructure instead of leaving them as unused liabilities.

The Haverhill project specifically required close coordination with Massachusetts' Department of Environmental Protection and the federal EPA to permit development on a former Superfund site, illustrating that this siting approach, while offering genuine land-use advantages, also carries meaningful regulatory complexity that a developer needs sustained expertise to navigate successfully across multiple similar projects.

 

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Why the Shift Toward Standardised 20 MWH Deployments Signals a Repeatable Model

 

Kearsarge's earlier projects, built between 2019 and 2022, ranged considerably in size, from Amesbury's 3.8 MWH system to William Way's 9.55 MWH facility, each seemingly sized to the specific site and local utility need. By contrast, the company's more recent 2025 and ongoing projects in Sterling, Concord, Middleborough and Chicopee all converge around a standardised 20 MWH capacity, suggesting the company has moved from a bespoke, site-by-site design approach toward a more repeatable, templated project size that can be deployed more efficiently across multiple municipal partners.

That standardisation likely reflects lessons learned from seven years of project delivery: once a developer identifies a battery size and configuration that reliably serves the peak-shaving needs of a typical municipal light department, replicating that same specification across new projects reduces both design time and procurement complexity compared with custom-engineering each new site's storage capacity from scratch.

 

What the Middleborough Savings Figure Reveals About the Underlying Economics

 

The Middleborough project's standalone 20 MWH battery is projected to save Middleboro Gas and Electric an estimated $12 million to $15 million over 20 years by reducing local peak demand during key grid events. That figure gives concrete financial substance to what "peak shaving" actually delivers for a municipal utility: peak demand periods typically require utilities to purchase electricity at significantly higher wholesale prices or pay demand charges tied to their highest usage moments, and a battery capable of discharging stored energy during exactly those peak windows can materially reduce a utility's overall electricity procurement costs over the asset's operating lifetime.

That savings figure also explains the underlying commercial logic driving municipal utilities to partner with Kearsarge repeatedly, including Chicopee Electric Light, where the partnership traces back to 2012, well before Kearsarge's battery storage projects specifically. Municipal light departments operate on typically tighter budgets than larger investor-owned utilities, making a multi-million-dollar cost reduction over two decades a genuinely significant financial benefit rather than a marginal efficiency gain.

 

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How the Orleans, Vermont Project Extends Beyond Massachusetts

 

Kearsarge's Orleans, Vermont project, developed with the Vermont Public Power Supply Authority and local light departments in Orleans and Barton, pairs a 20 MWH standalone battery with a nearby 7.5 MW solar array generating over 8.7 million kWh of renewable energy and credits annually, specifically structured to meet Vermont's state renewable energy requirements. That project represents Kearsarge's expansion beyond its original Massachusetts base into a second state with its own distinct renewable energy policy framework, suggesting the company's storage development model is proving adaptable across different state regulatory environments rather than being narrowly tailored to Massachusetts' specific incentive structure alone.

Managing Partner Andrew Bernstein framed the company's role over the past seven years as helping municipalities and local utilities think through how to adopt battery storage sustainably to meet accelerating community energy demands while driving affordability, a framing that positions Kearsarge's business model around solving a specific problem facing smaller, often resource-constrained municipal utilities navigating storage adoption largely on their own. Whether Kearsarge's planned 200 MWH of 2027 construction continues the standardised deployment pattern seen in its recent projects, and whether the company's expansion into Vermont signals further geographic diversification beyond its original Massachusetts municipal utility base, will indicate how much this development model scales as a template for smaller regional utilities navigating battery storage adoption more broadly.