On October 29th, 2012, Superstorm Sandy made landfall in New Jersey. Sandy brought wind gusts of up to 90 miles an hour into the Garden State, nearly a foot of rain in some locations and widespread flooding and devastation.
"These solar storage projects use sophisticated control systems to manage the integration between the solar systems, batteries and the PSE&G grid"
For Public Service Electric and Gas Company (PSE&G), New Jersey’s oldest and largest regulated electric and gas utility, Superstorm Sandy was the most powerful and destructive storm in its more than 100 year history. More than two million of PSE&G’s 2.2 million electric customers lost power during the storm, and it took the company nearly 10 days to fully restore all customers to service.
In the more than five years since the storm, PSE&G, which serves nearly three-quarters of New Jersey’s population, has made significant improvements to its infrastructure, communications and logistics that will keep more customers in service during a storm, and restore service faster in the aftermath.
One way that PSE&G is helping to make the electric grid more resilient and reliable is by building a number of solar storage projects in its New Jersey electric service territory as part of its Solar 4 All® program. Solar 4 All is a 158 megawatt-dc (MW-dc) program that utilizes rooftops, parking lots, utility poles and landfills/brownfields for large-scale, grid connected solar projects. As part of a 2013 extension to the program, the New Jersey Board of Public Utilities approved a 3 MW-dc carve out of the 158MW-dc total for PSE&G to build projects that integrate solar with other technologies to reduce the impact solar has on the grid and/or demonstrates reliability and grid resiliency for critical facilities during prolonged power outages.
There are four solar storage projects in service as part of this pilot program. One is at Hopewell Valley Central High School in Hopewell, NJ, the second is at Cooper University Health Care in Camden, NJ, the third is at the Caldwell, NJ Wastewater Treatment Plant and the fourth is at the Pennington, NJ Department of Public Works (DPW) building.
Although all four of these projects serve different types of PSE&G customers they all have the common goal of coupling solar power with battery storage technology to create a micro-grid for critical infrastructure in New Jersey. All four also provide solar power directly to PSE&G electric customers when the grid is operating normally.
• The Hopewell Valley Central High School solar storage project combines an 876 kilowatt-dc solar system with large lithium ion batteries. During a power outage, the solar storage system provides emergency power to the school that allows it to function as a community warming- station.
• The Cooper University Hospital project combines a 218 kilowatt-dc rooftop solar system with a battery storage system. During a power outage the solar storage system provides back-up power to refrigeration units that store vital pediatric medicines.
• The solar storage system at the Caldwell Wastewater Treatment Plant, located in West Caldwell, New Jersey, combines an 896 kilowatt-dc solar system with 1 megawatt-hour Eos Energy batteries. In the event of an extended power outage, the system works in conjunction with the treatment plant’s existing diesel back-up generators to allow the plant to operate for as long as 10 days without power.
• The Borough of Pennington, NJ DPW solar storage system combines a 404 kilowatt-dc solar system with 570 megawatt-hour Tesla Energy lithium-ion batteries. During an extended power outage, the solar storage system works to keep the DPW facility powered and operational. The Pennington DPW building is the epicenter to organize and provide vital services to the community during an outage.
These solar storage projects use sophisticated control systems to manage the connection between the solar, batteries and the PSE&G grid. Each battery system can participate in the PJM wholesale market for frequency regulation, which helps ensure the reliability and stability of the overall grid. If there’s an outage each solar storage system activates an automatic transfer switch (ATS) which disconnects the solar storage system from the grid and provides a micro-grid.
Beyond providing back-up power to critical facilities, the PSE&G solar storage projects provide other benefits as well. The solar panels at the four sites provide enough electricity to power about 400 homes a year, which avoids putting more than three million pounds of CO2 into the air. That is equivalent to removing more than 600,000 cars from the road for one year. The construction of the four projects provided jobs for the local construction industry and also continued PSE&G’s support of New Jersey’s solar development sector. And, finally, the solar storage systems demonstrate that solar can be successfully combined with batteries to increase grid resiliency and harden pieces of critical infrastructure from extended power outages which will hopefully spur the construction of similar projects in New Jersey and beyond.