How can offshore wind power a more sustainable energy infrastructure?
June 28, 2021
Adding more offshore wind power to our electrical grid can help us transition to a cleaner future
When we talk about the energy transition, there are many pieces to the puzzle. One of those pieces is wind power¡ªwhich has undergone incredible growth and advancements in the past decade.
Wind power, or energy generated by wind turbines, is a sustainable resource that can produce enough electricity to power major cities around the world. Lately, the focus has shifted to offshore wind power, where large farms of wind turbines are installed in bodies of water¡ªusually the ocean¡ªto take advantage of higher and more consistent wind speeds. This helps to generate substantially more electricity than onshore wind turbine facilities.
European countries have paved the way for other nations that are developing offshore wind production as part of their energy plans. Their offshore wind capacity has reached more than 22,000 megawatts (MW) from over 5,000 grid-connected wind turbines across 12 countries. Europe added almost 3,000 MW of offshore capacity during 2020 alone¡ªthat¡¯s just under 350 new offshore wind turbines now connected to the grid.
By 2030, offshore wind could contribute up to 100,000 MW of wind capacity to Europe¡¯s grid. So, how can the US and other countries, utilities, system operators, and developers work to adopt offshore wind power more effectively?
Block Island Offshore wind farm.
A new era of wind energy in the United States
The US recently approved the nation¡¯s first major offshore wind farm. Located off the coast of Massachusetts, the Vineyard Wind 1 project will generate 800 MW of electrical power. That¡¯s enough to serve 400,000 homes!
Electricity generated by the turbines will travel by cables buried below the ocean floor, make landfall on Cape Cod, and then travel underground to a new substation that will connect with the New England power grid. When finished, it will be the country¡¯s largest offshore wind installation.
The approval of this project signals a new era of wind energy across the US and feeds into the Biden Administration¡¯s larger climate action plan that was released in March 2021. Their goal is to deploy 30,000 MW of offshore wind capacity in coastal waters by 2030, or enough to power 15 million homes.
Even if the US meets half of these ambitious goals, it will be a giant step forward in the energy transition and advancements in the offshore wind market in the United States. Many developers are planning offshore wind projects along the east coast of the US¡ªsuch as Maine and Virginia¡ªas well as California. It is anticipated that offshore wind projects will then expand to the Gulf of Mexico, Puerto Rico, and the Great Lakes.?
Laying power cables at an offshore wind site.
Getting wind power to shore
One of the most frequent questions we¡¯re asked is: How does offshore wind power get to the shore? Electricity produced by offshore wind turbines travels to land through a series of submarine cables buried in the sea floor. Two types of transmission connections exist: High Voltage Alternating Current (HVAC) and High Voltage Direct Current (HVDC). Both connections transmit power from offshore platforms via submarine and underground cables to onshore substations. Once onshore, the electricity is interconnected with the electrical grid and then distributed to power homes, schools, and businesses.
As wind farm sizes get larger and the distances to shore increase, HVDC transmission often becomes the preferred means of transmitting power to the electrical power grid. The technology can transmit significantly more power through fewer cables over greater distances than HVAC transmission.
Nearly a decade ago, the proposed Atlantic Wind Connection project off the east coast of the US was a great example of the potential for an HVDC electrical transmission backbone to integrate offshore wind generation with the terrestrial power grid. The project was proposed to deliver up to 6,000 MW of power using 350 miles of cable that could be used to connect offshore wind farms that were built in the Atlantic Ocean miles off the coast.
Often referred to as a ¡°superhighway for clean energy,¡± the system's energy transmission capacity would have served approximately three million households on the east coast. Ultimately, the project did not move forward. Why? First, regulations governing transmission development projects made progress difficult and slow. Second, because the financing never lined up, the relatively lower cost of natural gas at the time made large-scale offshore wind uncompetitive in the market.?
Offshore wind is a key ingredient to the energy transition, and we must work to spread awareness of the several sustainable benefits it can bring.
Challenges to widespread adoption
An expensive price tag is not the only challenge that offshore wind projects and HVDC cable systems face. Apart from the harsh coastal conditions and equipment that must withstand extreme weather, one of the most pressing challenges is bringing the power back to the coast and, ultimately, connecting to the grid. With an increasing number of offshore wind farms being proposed, available cable landing locations with good connections to the onshore grid will be hard to come by. Foresight, good planning, integrated engineering/environmental evaluation, and efficient design will be critical success factors.
Permitting and environmental hurdles to offshore wind in the US also exist. According to the American Clean Power/American Wind Energy Association, the renewable power industry is more carefully regulated than that of Europe. In fact, many levels of the government won¡¯t fully review or release a permit until after the project has won a power purchase agreement.
The intermittent nature of offshore wind power¡ªnot unlike most renewables such as solar power¡ªis also often brought up as a concern. Critics question the affects that offshore wind has on the grid, as well as the ability to regularly meet our fluctuating electricity demands. In reality, offshore wind and solar power can work together to help with these fluctuations. As experience grows and new technologies (such as energy storage) come into play, we will learn more about balancing the grid and begin to focus on the numerous benefits that offshore wind power can provide.
An offshore HVDC converter platform.
A windy¡ªand sustainable¡ªfuture
Although there are several challenges to these bold projects, investment is still very important. Why? Because offshore wind can help guide us through the energy transition and lead us to a cleaner energy future.?
Discoveries from initial offshore wind farm projects on the east coast, such as Vineyard Wind and concepts like the Atlantic Wind Connection project, can lay the groundwork to start efficiently planning for more projects.
The good news? In addition to the Vineyard Wind Project, several projects in the US are now evaluating the benefits of HVDC systems to deliver power from offshore wind farms to the grid. These include a shared transmission system off the coast of New Jersey as well as a dozen other offshore wind projects along the east coast that are now under federal review in the US. We¡¯ll be watching these projects with high hopes of completion.
Offshore wind is a key component to the energy transition, and we must work to spread awareness of the several sustainable benefits it can bring. If we are truly aiming to reduce the effects of climate change, then wind energy is necessary on a global scale. Our futures benefit from¡ªand depend on¡ªthis renewable source of energy.