Offshore Wind Farm: Inexhaustible Energy for the World
The sea hides an unexpected wealth with more intense and constant winds than the land. The offshore wind farm is therefore becoming the fastest growing form of renewable energy. In fact, according to Wind Europe’s annual report, there are 110 facilities on European shores alone. These cover 11, 6% of the European Union’s energy demand.
There are also offshore wind farms in the United States and in Asian countries such as China and Japan. Floating or moored to the seabed, they are moving further away from the coastline and are becoming increasingly more powerful. They conquer markets with remarkable advantages over onshore farms. We’ll analyze them here.
How does an offshore wind farm work?
The operating principle of the offshore wind farm is the same as that of the onshore wind farm. It harnesses the power of the wind to move windmill blades. These blades are attached to turbines and wind turbines that convert the kinetic energy of the wind into electricity. After the electricity generation process, it is transformed to be distributed and transported to homes.
Beyond the obvious, there are big differences, however: they are installed in the sea – offshore – and, as we will see later, they are moving further and further offshore all the time.
The world’s first offshore wind farm was built in Denmark in 1987. It was the first wind farm to use marine wind turbines. Its predecessor, installed in Sweden, had these devices in the waters of the island of Lolland.
Offshore wind farm vs onshore wind farm: main differences
Let’s look at the main differences between offshore and onshore wind farms:
Onshore wind farms are located in depopulated rural areas. The engineers take into account weather factors, wind variations and soil conditions, in addition to accessibility and the legal standards in force.
Offshore wind farms, on the other hand, have no space constraints. Their visual and acoustic impact is much less. They are located on the coast or offshore. They can be anchored to the seabed or on floating platforms. Offshore wind farms can be anywhere in the world as long as the places meet the necessary conditions.
Offshore wind farms have mostly been developed in northern Europe. 77% of the facilities are located in the North Sea. There are 13% of the facilities in the Irish Sea. The Baltic Sea is home to 10%, including Wikinger, the largest wind complex implemented in the region by Iberdrola. Only 1% of the farms are located in the Atlantic Ocean.
An offshore wind farm is more powerful thanan onshore wind farm. As explained by the IDAE, Institute for the Diversification and Saving of Energy of the Spanish Government, the average unit power of ground wind turbines is 5MW. Meanwhile, the average rated capacity of installed marine turbines is 7.8 MW. This can reach up to 12 or even 15 MW.
There are several reasons why:
- The greater regularity and strength of sea winds.
- Lower required height of the towers.
- Less limitations for the transportation of components.
Installing an offshore wind farm is more expensive than assembling an onshore wind farm. The costliest aspects involved are logistics, construction and materials. Network connection and maintenance costs are also higher. This is due to difficulties in accessibility and equipment. The cost almost doubles those of the onshore facilities. In addition, they must be installed further and further away from the shore due to the depletion of coastal resources.
Onshore wind power generation is more mature than offshore wind power generation. Despite the progress, there are still a lot of unknowns, for example, environmental impact. Turbine manufacturers are more inclined towards the production of ground wind turbines and the availability of equipment and trained personnel is limited.
Onshore wind power generation technology has reached a point of maturity that does not promote many innovations beyond design and optimization. In contrast, the offshore wind farm is open to innovative strategies and technologies, for example, a combination of solar panels and wind rotors that provide power for developing economies and enable the construction of a smart grid.
Interesting facts about offshore wind farms
- The costs of offshore wind farms are declining thanks to the increased efficiency in the performance of ever-larger turbines.
- The country with the highest installed capacity is the United Kingdom. It has the three largest farms in the world, generating 59% of the total energy. One of them is the East Anglia ONE developed by Iberdrola, it is a huge achievement for the progress of renewable energy.
- China is the country with the largest number of new facilities. It is followed by the United Kingdom and Germany. Meanwhile, other markets such as the United States and those in the Asia Pacific region are growing rapidly.
- Germany leads the countries in new projects, with 38% of them.
- Leadership in the number of facilities remains firmly in the hands of Europe, which holds 75% of the global total.
- The average distance from an offshore wind farm to the coast is 59 km and the depth is 33 m. However, these figures continue to grow. The offshore wind farms are also getting bigger and bigger: their size has almost doubled over the past decade.
- Almost all of the offshore wind farms use the technology known as “fixed foundation”. In other words, these facilities are supported on the seabed. However, floating platforms allow for greater reduction in environmental impact and the opportunity to reach regions with greater wind potential.
Offshore wind farm, the future of blue economy
The energy generated by marine resources has been called “Blue energy”. Actually, it’s a specific form of energy. It has to do with taking advantage of pressure differences between freshwater and saltwater masses to generate electricity.
The concept of “blue economy” was created based on the potential for growth and innovation that seas and oceans have. Marine renewable energy has a leading role in blue economy. In accordance with the objectives set by the European Union, a real boom in this technology is expected.
Offshore wind energy will achieve these objectives:
- Reduce carbon.
- Make Europe carbon-neutral.
- Provide the main source of electricity. In fact, it is estimated that by 2030 offshore wind power generation will be higher than onshore wind power generation. In addition, it will cover 14% of the European Union’s demand. Production costs are expected to be reduced by giant turbines.
- Create jobs and promote the development of coastal areas. Every offshore wind farm built means new factories and innovations. For example, ports are built specifically to be used by the offshore wind energy sector. There’s not a lot of employment data yet. However, the UK plans to generate 30GW by 2030. This will involve tripling jobs and employing at least 33% of women in the sector. For example, the East Anglia ONE offshore wind farm, built by a consortium formed by Spain’s Iberdrola and the British group Macquaire, has generated 3,500 jobs for professionals and 100 for qualified technicians.
The offshore wind farm sectorhas enormous potential and is attracting more public and private investors than onshore wind energy.
Its generation capacity, compared to onshore capacity, forecasts that it can meet all current and future electricity needs from a clean and renewable resource, free of carbon emissions and with minimal environmental impact.
What seemed for a long time like an unattainable dream, and what used to be considered the energy of the future, is now here. Offshore wind farm energy will continue to advance with the unstoppable force of ocean winds: clean energy for a sustainable planet.
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