Eversource in December completed a non-wires alternative project via a battery-powered microgrid that meets the needs of 10,000 residents living in Provincetown, Mass., and three other outer Cape Cod towns.
With the outer Cape as its test case, the utility – which serves Massachusetts, Connecticut and New Hampshire – plans to utilize similar solutions in Connecticut and other parts of Massachusetts as a follow-up to this first project.
Non-wires alternatives — which include microgrids and other distributed energy resources — can help save money by averting the construction of expensive new distribution systems or upgrades. Because non-wires alternatives are generally local, clean energy, they can also be more environmentally friendly than poles and wires. They can either reduce electrical loads or boost energy production at a specific location.
Alex Tang, associate director of TRC, a consulting and engineering firm that was engineer for the Provincetown project, said that TRC is seeing utilities propose more non-wires solutions to address grid challenges; some of the challenges are sparked by new loads created from the electrification movement.
Provincetown, which is located at the tip of Cape Cod within the environmentally fragile and low-lying Cape Cod National Seashore, until recently was served by a single, 13-mile-long circuit from Eversource. Residents experienced numerous outages during storms that hit the town, which is surrounded on three sides by water.
Running wires and poles through the national seashore posed numerous challenges, including addressing environmental issues related to putting up wires and poles along the seashore.
The Provincetown microgrid is one of many non-wires projects Eversource and other utilities are planning or have implemented.
Eversource recently filed with the Public Utilities Regulatory Authority (PURA) in Connecticut for approval of three additional non-wires projects, said Anuj Mathur, manager of Eversource technology projects for grid modernization. The company is participating in PURA’s non-wires case.
Mathur declined to provide details, except to say that the projects are similar to the Provincetown project.
Non-wires alternatives elsewhere
Duke Energy recently deployed a non-wires microgrid under similar circumstances as Provincetown’s. The microgrid serves Hot Springs, North Carolina, a remote mountain town that gets power from the electric grid via a 10-mile, 22.86- kV feeder prone to extended outages.
Pepco is also looking into non-wires options to help meet its needs in the Washington, DC area. Pepco has identified a substation that is expected to exceed 5% of its existing transformers’ firm capacity by 2026.
And Pacific Gas & Electric (PG&E), has a remote grid program in which it employs standalone power systems such as solar and batteries to provide power to customers ln less-populated, high-fire threat areas. With no poles and wires, the remote systems reduce the risk of wildfires sparked by distribution equipment and also boost reliability, according to PG&E.
PG&E’s first remote grid is the Briceburg remote microgrid in Mariposa County.
The microgrid is in a fire-prone region outside of Yosemite National Park at the end of a long distribution line. The off-grid, hybrid Briceburg microgrid is expected to be the first of many installed to replace distribution systems in remote areas in PG&E territory.
Battery energy storage systems are often an important component of non-wires projects, said Tang.
“Battery energy storage systems can add flexibility to renewable energy sources – such as in PG&E’s remote grid program – to allow solar to become a dispatchable power source within a microgrid, but also provide utility scale grid support functions for resiliency and reliability purposes as demonstrated by Eversource,” he said.
How the Provincetown microgrid will work
On Cape Cod, the Eversource project will serve customers in Provincetown, Wellfleet, Truro and Eastham.
Eversource discussed the possibility of installing another circuit, but discovered that it made more sense to pursue a non-wires project.
The Provincetown microgrid system is made up of a front-of-the-meter, utility-owned 25 MW/38 MWh battery located in a 10,000-square-foot building, plus microgrid controls. The microgrid will be used specifically during outages, said Mathur. It can serve customers one to three hours during peak demand periods and up to 10 hours during off-peak hours.
The microgrid controller is made up of automatic switches, basically reclosers at the top of poles that redirect power and allow the system to island from the utility, said Mathur.
To ensure the project would be accepted by the local communities, TRC and Eversource worked with fire chiefs about fire safety concerns and also held a town hall early in the design phase, assuring the fire chiefs the system would meet the latest fire codes.
Eversource and TRC incorporated a new battery energy storage code that was adopted during the design phase of the project. The code, NFPA (National Fire Protection Association) 855, includes new fire safety requirements that aim to avoid battery overheating.
“We engaged early and were clear and concise. That helped push the project along with no hiccups on the public-facing side,” said Tang.
TRC is seeing more and more NWA projects in the Midwest and California, said Tang, and is now working on three NWA projects – two for a midwestern utility and one for PG&E’s remote grid program.
The midwestern utility is evaluating the possibility of deploying a large-scale battery to help provide reliability and to put off traditional, high-cost infrastructure upgrades.
TRC provided energy storage engineering and benefit-cost analyses for the utility, with an eye toward helping the utility decide how to make investment decisions deploying storage and other distributed energy resources.
On Cape Cod, the non-wires project is an innovative move for Eversource, its first ever non-wires alternative.
“It enhances reliability, improves response time and reduces power outage frequency. We’re looking at deploying other projects in a similar capacity to meet system planning needs.”
Track news about microgrids. Subscribe to the free Microgrid Knowledge Newsletter.
