Capturing the Multi-Faceted Value of Energy Storage - S&C Electric Company

Name of Project:
Capturing the Multi-Faceted Value of Energy Storage - S&C Electric Company
Minster, Ohio
Energy Storage System
S&C Electric Company
S&C Electric Company


The village of Minster, located in western Ohio, owns its own electrical distribution system. It serves approximately 2,800 residents and a number of high- profile industrial customers, including the  largest  U.S.  yogurt  factory.  In  late  2014, Minster  executed a power purchase agreement with Half Moon Ventures for the supply of power from a new 4.2-MW photovoltaic solar facility. The project goal was to expand the city’s electrical department’s footprint in renewable energy and provide cost-effective power. During design of the photovoltaic plant, Half Moon Ventures recommended expanding the project scope to include energy storage. For the inclusion of energy storage to make financial sense, the system had to capture multiple revenue  streams.


Requiring an experienced energy storage integrator, Half Moon Ventures turned to S&C Electric Company, which supplied complete engineering, procurement,  Half Moon Ventures chose S&C because, instead of using a piecemeal approach that involved packaging batteries, inverters, and the balance of plant  equipment together, S&C could deliver one cohesive solution. Half Moon Ventures preferred this approach because it would help eliminate scope   gaps, reduce project expenses, and ensure the Minster Electrical Department received the best long-term value. As an EPC provider, a power-conversion system manufacturer, and a medium-voltage switching and protection expert, S&C was well positioned to tackle the  sophisticated system.
S&C, with input from project stakeholders, selected a 7-MW/3-MWh energy storage system for the project. The system included S&C’s PureWave®SMS Storage Management System and an LG Chem lithium-ion (nickel manganese cobalt chemistry) battery system. S&C  engineers  designed  an  interconnect  system that includes medium-voltage transformers and  S&C switchgear to complement the energy storage  system.
During the initial design phase, S&C engineers collaborated with project partners to integrate three customized services into the system design. As the primary service, S&C designed the system to provide frequency regulation in the PJM Frequency RegD Market. To accomplish this, the battery system was sized for frequent charging and discharging   cycles.

S&C configured the PureWave SMS Control Platform   to interface with PJM market interfacing software to enable the system to follow a signal from PJM, which   is a regional transmission operator that coordinates  the movement of wholesale electricity in 13 states   and the District of Columbia. Based on grid conditions and market pricing, the system will generate revenue from either absorbing or dispatching energy.

As a secondary but congruent service to   frequency regulation, S&C designed the system to   provide var support to combat an occasional low power  factor on the system. Initially, the Minster Electrical Department contemplated installing capacitor banks to rectify the issue. However, S&C’s PureWave SMS was instead used to provide power-factor correction concurrent with frequency regulation services. Simultaneously with a full charge or discharge,   the system will provide 5.25 Mvar of power factor, both capacitive and inductive. This  eliminated the need to install approximately $350,000 of var-compensation equipment.

The third service S&C built into the design was demand response for peak-load contribution charge reduction. At the end of each year, PJM looks at    the five highest two-hour peak load periods across its entire territory. PJM then assesses a peak-load contribution charge to connected utility entities for

the load drawn during this time. To reduce this charge, the energy storage system software was designed to predict when these peaks would occur. During this period, approximately 10 times per year, the system  will switch from providing frequency-regulation services to demand response services to consequently help reduce the charge.

After S&C fully designed and manufactured the   system, S&C performed comprehensive Factory Acceptance Testing at its facility in Franklin, Wisconsin. S&C engineers performed tests and simulated real- world scenarios to ensure critical system-control components integrated together correctly. This proactive testing helped to reduce  commissioning time in the field and, more importantly, ensured the seamless integration of complex system    components.

The modular, containerized system design allowed for an easy installation. The power conversion   system and battery system arrived preassembled with the necessary  control  and  support  systems  installed. S&C used medium-voltage transformers, three 12.47- kV S&C PMH Pad-Mounted Switchgear units, and an S&C IntelliRupter® PulseCloser® Fault Interrupter to connect the energy storage system to the grid. This cohesive solution drastically simplified the  project for partners Half Moon Ventures and the Minster Electrical Department.

Valued Outcome

S&C was able to deliver an energy storage system capable of stacking revenues to ensure a strong   return on investment. S&C accomplished this by designing and fully integrating a system capable of three revenue streams: frequency-regulation services, transmission and distribution deferral, and demand- response  services.  Although  inherently  complex, S&C’s  strategic positioning and skills as an  experienced energy storage integrator helped to deliver a cohesive  solution.

At the time of commissioning, the system was one of the largest energy storage installations in Ohio. The Minster Electrical Department and Half Moon Ventures have aspirations to eventually perform islanding with the system to provide greater reliability to nearby industrial  customers.