The Daughters of Mary of the Immaculate Conception have long sought to make their facilities in Connecticut energy efficient and work with sustainability in mind. As early as 2015, the Daughters of Mary installed a substantial solar energy system at the New Britain site, and from there looked to expand the renewable resources on the campus.
That’s where Schneider Electric and Citizens Energy Corporation stepped in, at the direction of Ecosolar Installations and Associated Real Estate Services, to develop what they call a unique microgrid system that serves four different facilities at the site, in which all the buildings can generate or draw energy in unison, individually, or through a combination of each unit.
Through that setup, the microgrid can operate while being connected to the larger electric system, or in what the companies call island mode. That process allows the facilities to operate separately from the electric grid at or near normal capacity at times when energy resilience is needed, such as during a power outage.
It is one of Connecticut’s first microgrids capable of operating on 100% renewable energy, 24 hours, seven days a week, in island mode. This advanced project from Schneider Electric and Citizens Energy has been named a Top Project in the Environment+Energy Leader Awards 2023.
Richard Hepp, director of Schneider Electric’s Advanced Microgrids, says the DOM project was the company’s first to employ multiple microgrids within a single system.
“The first of its kind for us is the multiple microgrids within a single microgrid, four individual facilities that can couple and decouple as necessary for different buildings,” says Hepp. “You’ve got any combination. One microgrid might be running two of them, three, one in three, coupled, one in four, and two couples. All of them couple together if necessary. So that’s truly the first of the kind on that end.”
Citizens Energy Director of Resiliency Steve Bern says the project is even more unique.
Bern noted that the $7 million microgrid system is battery based but can run off renewable energy as well for an extended period of time, up to 19 days. It’s tied to the grid through multiple utility connections with each being individually metered. Then, all four buildings are interconnected across the campus.
“It’s cutting-edge technology,” says Bern.
The microgrid system is part of the late Mother Mary Jennifer Carroll’s vision to bring energy efficiency and resilience to the 137-acre campus. She was at the forefront of developing the first solar energy project at the site, which is also connected to the microgrid system.
The project was made possible especially to benefit critical facilities, necessary to stay operational and powered during outages or emergencies. Those facilities include senior care and other healthcare offerings.
That goal to keep those important facilities energy resilient and continuously operational helped the Daughters of Mary campus receive a $3.9 million grant from the Connecticut Department of Energy and Environmental Protection (CT DEEP), the largest completed for the microgrid development program. As part of the grant agreement, New Britain residents would be able to access the facilities in case of emergencies.
The microgrid system also uses technology developed through the Connecticut Green Bank’s Commercial Property Assessed Clean Energy Program (CPACE), which helps building owners secure low-interest financing to fund energy improvements.
The system combines 1.4 megawatt hours of battery storage capacity with 1.2 megawatts of solar generation. It also includes a 250-kilowatt natural gas generator for emergency use. Aside from resiliency, the microgrid can also provide the Daughters of Mary with utility cost savings.
Schneider Electric and Citizens Energy, working together for the first time, completed the financing, executed agreements, and coordinated other logistics by the end of 2020 with shovels in the ground by the middle of 2021. The microgrid system was fully operational by September 2022.
That doesn’t mean the work has stopped on the clean energy project.
Once in service, a microgrid goes through an ongoing optimization process, The systems and facilities are unique and never just work out of the box, the companies say. As such, they need tweaking to make sure the systems and algorithms are functioning properly and provide the services that are intended.
Tests and analysis have to be done to make sure the system keeps operating during multiple scenarios, including those that aren’t common, such as an accident that might take down power on a local level. There has to be enough energy reserved from charging through solar so that the battery is operational if an event does take place.
There are obvious events, such as a hurricane or other natural disasters, that would require the need for a microgrid and battery backup. It’s the 25 events that might not be so common or that a user doesn’t think about that is important to address, Bern says.
“So how do you manage that,” Bern asks. “We never bring the battery down to zero state of charge. We have limits in place and that’s how we’ve defined the algorithm. These aren’t defined in the book of microgrids of how to do it. Each system and facility are unique.”
That continuous work has kept the microgrid running, successful, and evolving. It takes adjusting during the moment to make sure the system is operating properly and safely, as well as staying on top of the engineering and optimization.
However, that has led to what Schneider Electric and Citizens Energy believe is the foundation to bring similar projects to communities and campuses where energy resilience may be tougher to implement through multiple buildings, sites, and grid connections. Colleges, hospitals, and inner cities could all benefit from similar energy platforms, which could connect multiple buildings in a localized area.
In the end, the Daughters of Mary microgrid project came together fairly quickly for Schneider Electric and Citizens Energy, but it was an ever-changing process with a lot of moving parts.
That has Hepp and Bern thrilled that the system, which originally looked like a simple solar-plus-battery platform and became much more, came together so successfully. The project’s success has the companies evaluating what this type of system could mean for similar energy transitions and technology enhancements in the future.
“This is a living, breathing microgrid,” Bern says. “You have to come out with the next generation of things. It’s evolving quick, but some of the designs that we are doing now are based off of what we did So, it’s pretty cool.”