1-413-589-0141 mmwec@mmwec.org Ludlow, MA

Energy Storage

Energy Storage

In an effort to help the Commonwealth of Massachusetts reach its carbon emissions reduction goals and adapt to an evolving hybrid grid, MMWEC’s Emerging Technologies Team is assisting its Member municipal utilities to integrate innovative resources such as energy storage into their portfolios.

MMWEC and its Members are serving as leaders in innovative technology through the use of Distributed Energy Resources (DERs), including lithium ion batteries and flywheels. Three MMWEC Members participated in the state’s Advancing Commonwealth Energy Storage (ACES) grant program through its Energy Storage Initiative, and were awarded grant funding in 2017. The Energy Storage Initiative aims to make Massachusetts a national leader in the emerging energy storage market.

MMWEC is assisting several of its Members, through its peak load forecasting and remote dispatch programs, to optimize the flexibility and benefits of their energy storage systems. 

Read on to learn more about the many energy storage projects MMWEC Members have installed so far.

West Boylston Municipal Light Plant Flywheel

West Boylston Municipal Light Plant (WBMLP) has installed a flywheel energy storage system (FESS), the first long-duration flywheel in the Northeast. The flywheel began operating on January 1, 2019.

The 128 kilowatt (kW) behind-the-meter FESS is interconnected through the plant’s existing 370 kW solar project. WBMLP’s flywheel system stores solar energy generated midday and discharges that energy during periods of peak usage in the afternoon and evening. WBMLP’s system contains 16 flywheels with a capacity of 8 kW each. 

The FESS uses electricity generated from the adjacent solar field as well as from the WBMLP distribution system to drive a motor that spins the steel flywheel, storing kinetic energy. It can rotate thousands of revolutions per minute, and once up to operating speed, that speed can be easily maintained using little more energy than is required to power a light bulb. When the flywheels are called upon to discharge energy, the motor then functions as a generator powered by the momentum of the flywheel, converting kinetic energy back to electricity.

Sterling Municipal Light Department Energy Storage Systems

Sterling Municipal Light Department (SMLD) made history when the department installed its 2 megawatt (MW), 3.9 megawatt hour (MWh) utility-scale battery project in 2016, the first of its kind in Massachusetts. SMLD was also the first light department to develop a community solar-plus-storage project in the state. Online since 2018, the 1 MW, 2 MWh battery is exclusively powered by its 1 MW community solar project.

 The SMLD projects have been visited and studied by utility professionals around the world and are frequently referenced as examples in energy storage webinars, meetings, and conferences.

Holyoke Gas & Electric Battery

Holyoke Gas & Electric’s Mt. Tom Energy Storage System pairs a lithium ion, utility-scale battery with the department’s Mt. Tom Solar Farm for a total capacity of 3 MW/6 MWh-AC.

Installed in 2018 and operated by Engie Storage, the system boasts both the largest utility-scale energy storage system and the largest community solar project in Massachusetts.

Ashburnham Municipal Light Plant Battery

Ashburnham Municipal Light Plant’s 3 MW, 5 MWh lithium ion battery went online in January 2019.

The project was made possible through an ACES grant, which covered 25 percent of the cost of the battery. The ACES program, a partnership between the Massachusetts Clean Energy Center (MassCEC) and the state Department of Energy Resources (DOER), is a competitive grant initiative aimed at piloting innovative, broadly-replicable energy storage projects to advance energy storage technologies in Massachusetts. The remaining cost of the project was funded through the pooled loan program operated by MMWEC.

Wakefield Municipal Gas & Light Department Battery

Wakefield Municipal Gas & Light Department’s (WMGLD’s) 3 MW, 5 MWh lithium ion battery became fully operational in March 2019. The system is directly connected to WMGLD’s Beebe Substation.

This project was also funded through an ACES grant, which covered approximately 30 percent of the cost of the battery. The remaining project costs were financed via the pooled loan program operated by MMWEC.

Templeton Municipal Light and Water Plant Battery

Templeton Municipal Light & Water Plant’s (TMLWP’s) 1.6 MW, 3.2 MWh utility-scale battery went online in May 2019.

The battery was designed with potential future needs in mind. It is tied into TMLWP’s circuit supporting senior housing, elder care, and an inpatient treatment center. The project’s design allows for future switching upgrades to the system that will allow the light department to island the circuit and supply the facilities solely with battery power, if needed.

TMLWP was the first member of MMWEC to install a standalone battery system without grant funding. Half of the project costs were funded through TMLWP and half were funded through MMWEC’s pooled loan program. As the demand for such batteries has grown and technology has improved, their costs have decreased, resulting in increased access and affordability.