Block Island

Block Island Wind Farm Profile

Overview

The Block Island Wind Farm is the first commercial offshore wind farm in the United States, located approximately 3.8 miles southeast of Block Island, Rhode Island, in the Atlantic Ocean. Developed by Deepwater Wind (now owned by Ørsted), the project became fully operational in December 2016.

Location and Size

• The wind farm is situated 3.8 miles off the coast of Block Island, Rhode Island.
• It covers an area of about 2 square kilometers.
• The project has a 30-mile visual impact assessment radius.

Project Details

• The wind farm consists of five GE Haliade 150-6MW offshore wind turbines, each with a 150-meter diameter rotor and a 6MW nameplate capacity. These turbines were the first commercial deployment of the Haliade 150-6MW model offshore.
• Each turbine stands 593 feet tall and is spaced approximately 0.5 miles apart, arranged in a single radial array roughly parallel to the southeastern shoreline of Block Island.

Foundation and Infrastructure

• The turbines are supported by fixed-bottom jacket foundations, which are steel structures with a lattice framework and multiple anchoring points to the sea bed. These foundations were fabricated by Gulf Island Fabrication and installed by a joint venture of Weeks Marine and Manson Construction.
• The use of fixed-bottom jackets reduced the use of steel and costs, and is safer and less disruptive to the ocean floor compared to other foundation types.

Electrical Connection

• The wind farm is connected to the national power grid via a 34.5kV submarine cable interconnecting the wind farm’s inter-array cable and a 34.5kV transmission cable. This cable, known as the Block Island Transmission System (BITS), is 21.8 miles long and conveys power to an interconnection point on Block Island and then to the mainland in Narragansett, Rhode Island.
• A new substation was constructed on Block Island, integrating with the existing power generation facility owned by the Block Island Power Company (BIPCO).

Environmental and Performance Benefits

• Energy Generation: The wind farm generates approximately 120,229 MWh of electricity annually, enough to power around 17,000 households. This replaces the previous reliance on diesel generators on Block Island, eliminating the need for up to 456,900 gallons of diesel fuel per year.
• Carbon Emissions Reduction: The project offsets about 121,000 tons of carbon dioxide emissions annually, equivalent to taking around 150,000 cars off the road.
• Marine Habitat: The turbines provide aquatic habitat for marine life, including cod, black sea bass, and mussels. Fishers have reported additional fish species and the establishment of mussels on the turbine bases.
• Noise Reduction: The wind farm reduces noise pollution by replacing the noisy diesel generators previously used on Block Island.

Economic Benefits

• Job Creation: The project created approximately 300 temporary local jobs during the construction phase.
• Tourism and Local Economy: The wind farm has contributed to a 19% increase in occupancy and a $3,490 increase in total monthly revenue for online home sharing marketplace properties on Block Island during peak tourism months.
• Cost Savings: The project reduces electric costs by 40% on Block Island.

Project Timeline and Licensing

• Permitting and Approvals: Key permits were obtained in 2014 from the Rhode Island Department of Environmental Management, the Bureau of Ocean Energy Management (BOEM), and the U.S. Army Corps of Engineers. A Special Use Permit was granted by the Town of New Shoreham Zoning Board of Review in 2012.
• Construction Phases: Construction began in 2015, with the installation of the first turbine foundation in July 2015. The project was fully operational by December 2016.

Contractors and Ownership

• Developer: Deepwater Wind, now owned by Ørsted.
• Turbine Supplier: GE Renewable Energy.
• Operations and Maintenance: GE Renewable Energy is responsible for operations and maintenance support for 15 years. Alstom (now part of GE) is also involved in the O&M contract.
• Other Contractors: Gulf Island Fabrication (steel jacket foundations), Specialty Diving Services (foundation substructures), Weeks Marine and Manson Construction (offshore foundation installation), and others.

Power Purchase Agreement

• The power generated is sold to National Grid under a 20-year power purchase agreement starting from 2016.

The Block Island Wind Farm serves as a pioneering project in the U.S. offshore wind industry, setting the stage for further developments along the East Coast and demonstrating the feasibility and benefits of offshore wind energy.