In general, the wind at sea not only blows more consistently but also significantly stronger than on land. The energy yield of a wind turbine grows with the third power of the wind speed (Betz’s law). This strong dependency means that a plant in a good location, where the wind blows twice as strong/fast as in a worse location, can produce up to eight times as much electricity. For this reason, it pays off when planning wind turbines, to pay a lot of attention to the location where it is built.
Many of the concerns that residents, as well as landscape and nature conservationists, often put forward about wind power locations on land no longer apply at sea. As examples, the landscape and agricultural areas are preserved, and noise pollution for residents is eliminated.
Challenges of offshore wind energy
Technically, offshore locations present wind turbine manufacturers with significant challenges. Due to higher wind speeds, the masts and rotors need to withstand significantly higher mechanical loads than systems on land. But also the foundations, the anchoring on the seabed, and masts underwater must be designed to be more stable to withstand waves, tides, ocean currents, ice drifts, and storm surges. The materials used must not be corroded too quickly by seawater and salty sea air. The connection of the generated electricity to the power grid is also more difficult, as in most cases submarine cables are laid to the nearest coast, and those must be particularly resistant to external influences. This effort is then reflected in the electricity price and high energy consumption in the construction phase. Once the system has been in operation for a certain time, it compensates for the large amount of energy that was used in the construction phase. However, it again depends on the location and effectiveness of the systems how long it takes.
Biden administration announces a major offshore wind plan
President Joe Biden’s administration wants to expand offshore wind on America’s shores with the help of billions of dollars in investment. The construction of wind farms should provide more than ten million households with environmentally-friendly electricity by 2030. The aim is to produce 30 gigawatts of wind energy. This will require more than USD 12 billion of investment along the Atlantic and Pacific coasts. It would also create tens of thousands of new jobs.
Offshore wind energy as part of the overall solution
As with solar, wind power is subject to weather fluctuations and thus also fluctuations in electricity production. Therefore, it must always be considered to have buffers and reserve power plants, which are often not renewable. Offshore wind energy is a clean, renewable energy source that can reduce the need for fossil fuels, and help tackle climate change. It is not the best way to produce energy, as construction and maintenance are complex and expensive, but as part of the solution, offshore wind power is indispensable to achieve global climate targets. The necessary effort will likely be reflected in rising electricity costs.