Project Overview

Underground Work (Downtown)

The underground cable work, which will enhance reliability and improve restoration times, began earlier this spring. The crews will be demobilizing for the summer months, but will return to complete the balance of the work this fall (Sept/Oct 2025). The work is expected to be complete by the end of 2025.

Installation of New L8 Feeder Complete

National Grid has completed the installation of the new L8 feeder between Downtown and Milestone Road ahead of the anticipated summer peak load on the Island. In a number locations we were able to slightly shift the placement of the new poles to allow for greater access along the Island’s sidewalks, creating a safer pedestrian pathway. Some work still remains post-construction, including the removal of some of the old poles. Unfortunately, National Grid does not control this schedule as the removal is predicated on other utilities (phone, internet, emergency communications, etc.) transferring their wires to the new poles. However, we are all working together to complete the removal as quickly as possible. We greatly appreciate the cooperation of the local residents and businesses as we worked to complete this critical installation.

In addition to the extensive energy efficiency efforts that have been in place on Nantucket for several years, National Grid’s IslandReady: A Nantucket Electricity Initiative proposes a multi-faceted, holistic approach to upgrading the Island’s electrical infrastructure, ultimately providing residents and businesses with safe and more reliable electric service.

There are three main components that make up National Grid’s IslandReady project:

Candle Street Substation Upgrades:

• Three existing switchgear boxes housed at the substation (used to control and protect substation equipment) , along with a new (fourth) switchgear box, will be relocated within the property and placed on a newly constructed platform to provide increased reliability and safety (anticipated completion: TBD)
• Transformer controls also will be relocated from the sides of the existing transformers to inside the control house (brick building) on the property to provide protection from potential flood waters (this work was completed in Spring 2018)

Distribution System Upgrades:

• Installation of a new feeder (L8) will create increased capacity for the east side of Nantucket (Milestone Road area), improve switching ability on the Island’s distribution network, and reduce the potential for outages on other feeders, which serve critical facilities such as the hospital, airport, and wastewater treatment facility (Completed June 2020)
• The existing underground cable located downtown will be upgraded – including the installation of new underground conduit and larger manholes – to improve reliability and decrease outages, and to meet increased capacity needs (anticipated completion: TBD)

Back-up Generation & Battery Storage:

• A new diesel-powered generator will replace two aging generators at National Grid’s Bunker Road facility (Completed Fall 2019)
• A new Battery Energy Storage System will also be installed at Bunker Road to reduce loading on the cables (Completed Fall 2019)

Download IslandReady Fact Sheet (PDF)