Humans have harnessed the power of wind for thousands of years whether through sails or windmills. The offshore wind industry traces its modern roots to 10 wind turbines just off the Denmark Coast in 1991. In the 30 years since, countries around the world have built tens of thousands of turbines in over 160 offshore wind projects, generating 32,000 MW of power.
While land-based wind turbines are now a common sight across the United States, they have important differences from offshore wind turbines that require a different industry to support development. Modern offshore wind turbines and blades can reach heights over 800 feet and require large components that can only be transported by water. This requires the constant transport of supplies and materials by sea. The actual installation of an offshore wind project is far more complex than a land wind project. Offshore wind projects require specialized equipment, vessels, training and extensive stakeholder engagement and environmental review. Projects can take years, even up to a decade to complete because of the complexity of building an offshore wind project.
Although construction can be challenging, offshore wind projects can produce much more power than their land-based predecessors. Offshore wind turbines capture oceanic wind, which blows more powerfully and consistently than on land, increasing a turbine’s power output and reliability. This effect is further enhanced by a turbine’s blade length, which sweeps over a much larger area and captures more wind. Offshore wind can be an attractive power resource to states and countries that lack available land to develop solar or land-based wind power but have good access to areas offshore from their coasts.
- U.S. Wind Farm Locations
Nearly two dozen projects are moving forward in the United States. Most activity is localized on the East Coast, an ideal location for offshore wind development due to strong winds, shallow waters, and proximity to major population centers. U.S. offshore wind turbines currently use foundations fixed directly to the ocean floor in the shallow waters of the Atlantic Outer Continental Shelf to allow for easier installation. While development has primarily occurred in the Atlantic Ocean, the federal government recently initiated siting processes to expand offshore wind to the Pacific Ocean and the Gulf of Mexico, making offshore wind a national industry.
(Source: BOEM: National Renewable Energy Program)
- How Electricity is Generated
Offshore wind harnesses the power of wind to generate clean, renewable electricity. Wind power is generated by converting kinetic wind energy into mechanical energy, and then electric energy. Blowing wind turns turbine blades connected to a rotor, and the rotor then rotates drivetrains or gearboxes to generate electricity. From there, the generated electricity travels by cables to offshore and onshore substations, which connect to the electricity grid where it is delivered to homes and businesses.
Parts of an Offshore Wind Power Generation System
- 1.Wind Tower Generator Foundations & Substructions: These are the structures that support the offshore wind turbines. The support structure can either be fixed to the ocean floor or utilize floating turbine technology that moors the floating foundation in place. The structures are manufactured from steel or concrete.
- 2.Inter-Array Cables: These cables deliver power from each turbine to a centralized offshore substation or multiple substations.
- 3.Wind Turbine Generator: The wind turbine generator consists of a rotor (blades & hub), a nacelle (which houses the components generating electricity), a tower, and a transition piece that connects the tower to the foundation. Towers and transition pieces are made from steel and concrete, and blades are constructed out of composite materials.
- 4.Offshore Substation Platform or Structure: The offshore substation collects the power from the wind project and prepares it to be sent to an onshore substation.
- 5.Export Cable: Power from the wind project is exported from the offshore substation to an onshore substation via one, or more, export cables.
- 6.Onshore Substation: Export cables deliver power to an onshore substation that connects and synchronizes it to the grid.
Want to learn more? Visit the federal government’s Office Energy Efficiency & Renewable Energy.
- The Role of Ports & Vessels
Ports and vessels are critical to the construction and operation of an offshore wind project, and Maryland’s rich maritime history means the state is well positioned to support this new industry. Normally, a range of port types are required in service of offshore wind development, including ports for manufacturing, marshalling of materials (or the staging of project components), assembly, and storage (also known as “laydown”).
Maryland’s offshore wind project developers for Momentum Wind and Skipjack have both selected Tradepoint Atlantic, located at Sparrows Point in Baltimore County, MD, to be the center of this maritime activity. That means project components, like towers, foundations, and blades, will either be manufactured in Baltimore or shipped from other locations for final assembly, and then sent out to be installed in the offshore wind projects. Many different types of ships will be moving in and out of Baltimore harbor to complete these tasks and will require services and general maintenance.
While the Baltimore area will be utilized to help construct and install Maryland’s offshore wind projects, the harbor’s distance from the wind projects makes it difficult to conduct routine maintenance required to keep the turbines operational over the next 20 – 30 years. Instead, Operations & Maintenance (O&M) ports will be located much closer to the project areas in Ocean City, MD, which is about 100 miles southeast from Baltimore on Maryland’s Eastern Shore. Small craft called Crew Transfer Vessels (CTVs) will transport technicians out to the turbines to perform maintenance and repairs when needed.
Before construction can begin, U.S. ports need to be identified as suitable for use and upgraded to ensure they can support the weight and size of offshore wind components. Ideal ports will have large areas for marshalling or laydown activities, strong enough land and docks to bear the weight of offshore wind components, the capacity to host cranes large enough to lift towers and monopiles, and waterways deep enough to allow larger vessels to access. Upgrade work has already begun at Tradepoint Atlantic where local companies and workers have been busy rebuilding the port facilities and docks. Construction will also soon begin on an O&M port in Ocean City, where Skipjack’s project developer announced in late 2021 that it secured property in West Ocean City for a $20 million emissions free facility. US Wind, project developer for MarWin and Momentum Wind, is also expected to secure its own O&M facility near Ocean City.
- Federal and State Roles
The federal government has jurisdiction over activities on the Atlantic Outer Continental Shelf between 3 – 200 miles out to sea and handles the permitting of nearly all offshore wind lease areas through the Bureau of Ocean Energy Management (BOEM). To ensure that a project is constructed in an environmentally responsible manner and does not significantly disrupt other ocean-users, the federal government extensively studies a project area and construction plan before issuing permits, a process that can take 10 years or more.
BOEM began the process for identifying suitable sites for offshore wind development in 2010 by bringing together various stakeholders, including local governments and tribes, in what is called an Intergovernmental Task Force. This siting process worked to identify potential lease areas that did not adversely impact environmentally sensitive areas or significantly interfere with other ocean user activities like military operations and shipping. Normally, a wide area, sometimes called a Call Area, is significantly narrowed down over years of stakeholder engagement into Wind Energy Areas (WEAs) and finally lease areas. After identifying suitable areas off the Delmarva Peninsula, BOEM solicited commercial interest from project developers. In 2014, US Wind won a competitive auction for the wind area off the Maryland coast for $8.7 million. The Delaware wind area did not receive sufficient commercial interest to warrant an auction, and in 2012 was granted to Bluewater Wind Delaware; the area was later sold to current leaseholder Ørsted. A more detailed history of each lease can be found on BOEM’s website.
- BOEM’s Webpage on Maryland State Leasing Information
- BOEM’s Webpage on Delaware State Leasing Information
With leases secure, each project must go through years of evaluation and analysis by BOEM to ensure the projects are in the public’s interest and built in an environmentally responsible manner. This will include reports on potential impacts to marine and avian species, navigational safety, fisheries, and economic development. This review process will conclude with a Construction and Operations Plan (COP) in which project developers explain in detail where turbines and cables will be located and how they plan to construct, operate, and decommission the wind projects.
In all stages of siting, collaboration, and analysis, public engagement is essential and encouraged.
Learn more about BOEM’s rigorous permitting process here.
STATE POWER PROCUREMENT REQUIREMENTS
State governments play a crucial role in offshore wind development by passing laws or enacting policies that require offshore wind power to be part of a state’s sources of energy. Maryland is one of at least ten states that currently require or have set goals to develop offshore wind power. States can either enter contracts with a wind developer to purchase power directly or require state utilities to source a percentage of their energy from offshore wind projects. As part of this process, states create standards to ensure projects are cost-effective, provide best value to electricity ratepayers, incentivize local economic development, utilize local ports, and hire local labor.
Maryland’s laws and policies require any project receiving an Offshore Wind Renewable Energy Credit (OREC), the state’s procurement mechanism, provide a positive net benefit to Maryland’s economy, public health and environment. Maryland’s OREC process also ensures offshore wind projects conform to labor standards, and include minority, women, and veteran-owned businesses participation in the local supply chain. More details about how Maryland procures offshore wind power in the history section.