With its proximity to offshore wind energy areas, maritime workforce, and port infrastructure, the SouthCoast region is well suited to grow an offshore wind industry cluster with well-paying jobs, and supply chain and economic development opportunities.
Our offshore wind lease area, which is located 30 miles south of Martha’s Vineyard and 20 miles south of Nantucket has the potential to generate more than 2,400 MW of clean renewable energy which is enough to power more than one million homes.
Mayflower Wind will deliver the first 1,200 MW of energy via the Mayflower Wind SouthCoast Project, connecting to the New England regional electric grid at Brayton Point, in Somerset, MA. We expect to deliver clean energy from the project by the end of the 2020s.
Getting from there to here
The Mayflower Wind SouthCoast Project will be located over 60 miles south of Rhode Island.
Submarine cable routing from the lease area to Brayton Point is still being determined and will based upon ongoing surveys, studies, and the permitting process.
The proposed routing would extend northwest from the lease area, through federal and Rhode Island state waters, the Sakonnet River, with a buried intermediate underground crossing in Portsmouth, Rhode Island and then continuing through Mount Hope Bay, and ending at the Brayton Point grid connection in Somerset, Massachusetts.
Offshore to onshore connection
Wind Turbines (WTGs) – Wind turbines convert kinetic energy from the wind into electric power
Foundations – A substructure extends upwards from the seabed and connects the base of the tower, while a foundation transfers the loads acting on the structure into the seabed.
Inter-array Cables – Electrical cables connect wind turbines to each other and transport power to the offshore substation at 69 kilovolts (kV) alternating current.
Offshore HVDC Converter Substation – The offshore substation enables the wind farm to operate more efficiently by converting the voltage from 69 kV to +/- 320 kV direct current.
Offshore Export Cables – Electric power is transmitted from the offshore substation by electrical cables which will come ashore in Portsmouth.
Intermediate Landfall – The export cables connect onshore via an underground conduit tunneled deep beneath the beach.
Onshore Underground Export Cables – From the beach area, electric cables will be buried beneath roadways or shoulders, before making an exit into Mount Hope Bay.
Terminal Landfall – The export cables connect onshore via an underground landfall at Brayton Point.
Onshore HVDC Converter Substation – The onshore station transforms the power to grid voltage 345 kV alternating current.
Underground Interconnection Cables – A 345 kV underground cable transports the power to an existing substation station.
POI – The point of interconnection, or the point where Mayflower Wind’s facilities interconnect with the Transmission Owner’s facilities.
Transmission System – An interconnected network of 345 and 115 kV transmission lines that deliver electricity to end customers.
Mayflower Wind has identified potential locations for the subsea export cables to make intermediate landfall and cross underneath Portsmouth, Rhode Island with minimal impact to the local community and natural resources.
Routing analysis for the onshore transmission infrastructure takes into consideration multiple factors, such as feasibility for construction, environmental resources, social impact, cultural resources, and other local concerns. The objective is to minimize impacts while aligning with safety and engineering considerations.
The cables will be installed via Horizontal Directional Drilling under the beach and coastal ecosystem before making landfall at Boyd’s Lane/Park Avenue. Once ashore, the cables will continue underneath public roadways, along three potential routes: northwest towards the Mount Hope Bridge, or northeast towards Anthony Road.
The routing is intended to avoid a narrow and highly constrained area of the Sakonnet River at the Old Stone Bridge and Sakonnet River Bridge.
After exiting beneath Portsmouth and traveling up Mount Hope Bay, there are two potential locations for the subsea export cables to make landfall at Brayton Point.
Again, using HDD, the cables will be installed underneath the Brayton Point property and connect to a new onshore high voltage direct current converter station on the site. The proposed converter station site would consist of approximately 8 acres.
A buried alternating current cable will exit and link to the nearby National Grid substation. Construction will be entirely within the previously disturbed, industrial site.
Studies are being conducted to gather data and assess the suitability of these sites for a complete and reasoned analysis of preferred and alternate routes.
A final decision on routing will be made after a full analysis has been completed. That decision will then be reviewed and require approval by state and local regulatory agencies.
Dig deeper. How horizontal directional drilling works
HDD is the preferred method for installing cable and pipe infrastructure in a manner that minimizes risks to natural resources, flooding, and erosion. Offshore, the proposed target burial depth is 6 ft below level seabed. The proposed range of acceptable burial depths is 3- 13 ft. When the cables transition to HDD burial at the approach to shore, cable burial depth will increase to approximately 40 feet below the seabed and below the ground. Permanent surface impacts will be minimal.
The intermediate Portsmouth crossing will use HDD at two locations, entering and exiting Aquidneck Island. The process begins with the creating of a bore hole to support the cable. It will be located well below the surface and will come up well distant of the shoreline.
After the bore hole is created, the cable will be pulled through and buried underneath the surface. The cables will be installed in up to two cable bundles, each consisting of two power cables and one dedicated communications cable.
How HVDC conversion works
The project will use state-of-the-art HVDC technology that minimizes marine cabling, reduces energy losses, and strengthens the New England grid.
The onshore converter station at Brayton Point will be a specialized electrical substation designed to convert the HVDC power from the export cables to HVAC power to enable interconnection to the existing transmission infrastructure.
The converter station will contain equipment necessary to provide power quality conditioning to ensure that the proposed Project’s connection meets the technical requirements administered by the regional grid operator, ISO-NE.
Substation/converter station buildings are anticipated to be pre-engineered metal panel buildings or precast concrete buildings depending on thermal design requirements. A new underground 345-kV transmission line will be constructed entirely within the previously disturbed, industrial site. The underground transmission line will connect the converter station to the existing point of interconnection, the National Grid substation, at Brayton Point in Somerset, Massachusetts.
A strong commitment to safety
While we will examine the safety of all aspects of the project, one topic of community interest is electro-magnetic fields (EMF). We hired expert consultants to study the potential EMF effects of the cable. They found that there are no safety risks and Mayflower’s electric cables will operate well below established health guidelines. For more information and to view the reports, please see our Health and Safety page.
Your input is valued during the regulatory review process
Mayflower Wind requires local, state, and federal permits and approvals for its nearshore and onshore facilities and activities in Portsmouth, Rhode Island and Somerset, Massachusetts.
The regulatory review process provides numerous public meetings and comment periods, under the direction of lead federal and state agencies, when you can provide input into the various aspects of the project.
Permitting applications and other regulatory documents are available on the documents page.
MA & RI state permitting
Status: MEPA ENF & EFSB Petitions filed. See documents.
MEPA Remote Consultation Session
Thursday, September 15 at 6:00 pm
Join via Phone: 646-568-7788
Meeting ID: 952-237-06206
For more information:
See the MA EFSB and DPU Siting Process
See the RI EFSB Siting Process
Benefits to the SouthCoast
Mayflower opened an office in downtown Fall River in September 2021. We will have regular office hours for interested individuals and groups to stop by, meet with staff and learn more about the project and opportunities with the company. See our events page or contact our community liaison for more details.
Investing in the ports and coastal infrastructure of Southeastern Massachusetts will build a firm foundation for the offshore wind industry. Mayflower Wind is committed to locating port facility operations in areas that offer cost-effective returns for the project while supporting the SouthCoast’s long-term growth and development goals.
Mayflower Wind’s operations & maintenance base will be a new landmark on the Fall River waterfront, providing an anchor for offshore wind related development. We intend to redevelop six acres of land to accommodate and support continuous 24/7 operations. Facilities will be equipped with a shoreside cargo crane for the lifting of large wind turbine components.
There will be several hundred permanent, high quality, long term jobs operating and maintaining the offshore wind farm – all based at the Fall River facility, a few with desks, some working in the warehouse, and the majority traveling out to the offshore wind lease area regularly, either on the Fall River based service operations vessel (SOVs), on which workers live on-board for weeks at a time, or the New Bedford based crew transfer vessels (CTVs) that will shuttle back and forth on a daily basis.
Mayflower Wind has signed a lease agreement to utilize the New Bedford Marine Commerce Terminal as the primary staging and deployment base during the project’s construction.
Through our multi-party agreement with Gladding-Hearn Shipbuilding/Duclos Corporation, an industry-leading, Jones Act compliant, hybrid battery diesel electric CTV will be designed and manufactured in Somerset, MA.
Mayflower Wind is also an active supporter of science, technology, engineering, and mathematics programs (STEM), and renewable energy education programs for local students. We support local workforce training, in collaboration with existing vocational schools, community colleges and other area providers.
Mayflower Wind is active on the SouthCoast. We are members of the One SouthCoast Chamber and support several educational institutions, training and fisheries programs.
Mayflower Wind is committed to provide energy-saving, affordable, and quality housing to the SouthCoast community. Working with Buzzards Bay Habitat for Humanity, we aim to invest in 40 homes over the next decade that will deliver substantial energy savings and assist the area’s low-income residents.
We have pledged to have a diverse and inclusive workforce that includes developing programs to recruit, train, and retain as well as procurement/contracting opportunities for women, people of color, indigenous people, veterans, LGBT, and people living with disabilities.
We are actively seeking opportunities to partner with local businesses on the SouthCoast. We encourage interested and suppliers to register with us.
Through partnerships with Bristol Community College/National Offshore Wind Institute and the Massachusetts Maritime Academy, we will offer training to Massachusetts residents at every level of the offshore wind industry – from turbine installation, operation and maintenance, to project management – in order to equip tomorrow’s offshore wind workers, especially for the benefit of local communities. Our investments in entrepreneurial initiatives will spur new technologies, services, and businesses as part of a regional blue economy cluster.
Ways to get involved
We are reaching out to the SouthCoast and Rhode Island communities and are committed to ensure all Portsmouth and Somerset residents can learn about our project, ask questions, and provide valuable input.
Contact our community liaison
Dugan Becker is the project’s SouthCoast Community Liaison Officer. In this role, Dugan serves as the link between the community and Mayflower Wind. He listens to residents and shares project updates and information to strengthen communication and collaboration.
This page will be updated frequently so we encourage you to visit often and/or sign up for our email updates.
Frequently asked questions
How will the project benefit the SouthCoast?
The SouthCoast region will benefit from hosting a major clean energy infrastructure project through additional revenue, local jobs, and business activity. The Mayflower Wind project is anticipated to support over 14,000 jobs. Mayflower Wind is committed to invest $42 million over 20 years through partnerships that are focused on bringing jobs and investment to the SouthCoast and its historically disadvantaged communities, plans to repower Brayton Point, regenerate Fall River, and reinforce the thriving and growing port community of New Bedford. Mayflower Wind’s economic development and community support efforts will lay a foundation for a new vital business and employment cluster for the Commonwealth and the SouthCoast.
Mayflower Wind looks forward to being a long-term and reliable partner in the SouthCoast community.
What ports will the project use?
Mayflower Wind has signed a lease option with the Commonwealth of Massachusetts to utilize the New Bedford Marine Commerce Terminal as the primary staging and deployment base. The project is reviewing other cost-effective locations for staging, assembling, and deployment. Key criteria include size, air draft, horizontal clearance, and depth at berth.
Why don’t the offshore wind developers use a shared transmission cable system?
Each leaseholder bears the sole risks and responsibilities for delivering power to a point of interconnection on the regional grid.
The regional Independent System Operator enforces a “single-source contingency” rule that limits the capacity of a single project at a single point of grid interconnection to no more than 1,200 megawatts. In addition to this rule, existing conditions further limit how much energy can be injected at a specific location without major upgrades to the system.
The Massachusetts Department of Energy Resources evaluated the merits of a coordinated offshore transmission network in 2020, and found that the costs outweigh the benefits. A major investment in new onshore grid infrastructure would create greater value for all customers, by enabling full maximization of the offshore wind resources.
In order to generate the full potential of the lease areas, multiple export delivery cables will be constructed from each lease area to shore, at different grid connection points.
How does Mayflower Wind support diversity, equity, and inclusion?
Mayflower Wind has crafted its diversity, equity and inclusion (DEI) plans with the goal of increasing the diversity of its internal staff, as well as its external partners. We believe that increasing diversity at every level of the organization can bring a wider range of experience and perspectives, resulting in better decision outcomes, which in turn will mean a better delivered project, and ultimately more benefits to the Commonwealth as it continues to fight climate change and racial and social inequities.
What commitments has the project made to support investments in ports and infrastructure, workforce development, scientific research and innovation in Massachusetts?
Mayflower Wind is committed to invest over $115 million in initiatives that will help make the Commonwealth and SouthCoast region a hub for offshore wind. This total investment is based on commitments made under the Massachusetts offshore wind procurement awards:
- $42.4 million, offered under the Section 83C III solicitation, with a focus on education, training, and workforce development; diversity, equity and inclusion; and low-income ratepayer support; and,
- $77.5 million, offered under the Section 83C II solicitation, that set a framework towards ports and infrastructure improvements; workforce training and development; applied research and innovation; marine science; and low-income ratepayer support.
Economic Benefits from MA 83CII & 83CIII
Offshore Wind Energy Procurements