PSE&G cuts ribbon at wastewater treatment plant solar storage project

CALDWELL, NJ — Officials from PSE&G and Caldwell cut the ribbon Oct. 25 on a solar storage project that will help keep the borough’s wastewater treatment plant running during an extended power outage as a result of severe weather. The Caldwell solar storage system is one of three similar projects that are in service as part of PSE&G’s “Solar 4 All” program and the ribbon cutting comes nearly five years to the day that Superstorm Sandy made landfall in New Jersey, causing extensive damage and outages.

The Caldwell solar storage system combines a 2,682-panel, 896-kilowatt-dc solar system with 1-megawatt-hour batteries. During normal operation, the solar system provides electricity directly to the grid and can power approximately 165 homes annually. In the event of an extended power outage, the combined solar and battery system works in conjunction with the treatment plant’s existing diesel backup generators. During the day, the solar panels recharge the batteries and help power the wastewater treatment plant and at night the batteries help keep the facility running.

“I’d like to thank PSE&G for choosing the Caldwell wastewater treatment plant as the location for this valuable solar project, which will not only provide power to the grid on a daily basis, but will also keep our plant up and running in the event of an emergency, such as a hurricane,” Caldwell Mayor Ann Dassing said in a press release. “I’d like to also thank everyone from Caldwell who was involved for both bringing this opportunity to the borough’s attention and for working alongside PSE&G to make it a reality.”

The combination of the new solar storage system and the existing backup generators will allow the Caldwell plant to operate for as long as 10 days without outside power, which will help keep wastewater from the facility out of local waterways. The solar storage system can also participate in PJM’s frequency regulation market.

“The PSE&G solar storage project at the Caldwell wastewater treatment plant is a great example of how a public/private partnership can work to benefit the people of New Jersey,” State Sen. Richard J. Codey said in the release. “We are already a national leader when it comes to solar power, so it makes sense to take renewable energy a step further and use it in a way that helps make our state more resilient to storms.”

“PSE&G has taken a number of major steps during the past several years to both harden our electric grid in the face of major storms and also make it more resilient,” Courtney McCormick, vice president renewables and energy solutions at PSE&G, said in the release. “The Caldwell wastewater treatment plant and our other solar storage projects around the state are an important part of that work because they all demonstrate how well-suited solar storage is for ensuring the reliability and resiliency of critical pieces of infrastructure.”

The Caldwell wastewater treatment plant solar storage system is part of a 3-megawatt-dc carve-out in the “Solar 4 All” program dedicated to developing projects that integrate solar with other technologies to reduce the impact solar has on the grid or increase reliability and grid resiliency for critical facilities during prolonged power outages. The two other PSE&G solar storage projects in service are located at Hopewell Valley Regional High School in Hopewell and at Cooper University Hospital in Camden. The former allows the high school to serve as a warming or cooling station for the public during an extended power outage and the latter provides backup power for refrigeration needed for vital pediatric medications at the hospital.


Advanced Solar Power of Flemington was the engineering, procurement and construction contractor for the Caldwell project. Eos Energy Storage of Edison supplied the batteries, Siemens AG integrated the batteries and solar system, and A.F. Mensah of Princeton is the storage system operator.