Latest update from offshore wind turbines

Man has always been fascinated by open seas and high winds. Huge sail ships made early sailors explore the world. Today, they help us make clean electricity. Without buildings and trees, wind in the sea can blow steadily for a long time, gliding over the smooth surface of water. This makes open seas the perfect place for wind turbines. On land, wind turbines are built in open, rural areas without trees or buldings. Yet this is no match for wind turbines in midsea as they make three times more electricity than wind turbines on land.

At first, wind turbines were built close to the sea shore, on huge concrete foundations rising up from the ocean floor. Cables and overhead lines transferred electricity to power stations. But they were difficult and expensive to build. So, focus has shifted to floating wind turbines built far from the shore, called floating offshore wind turbines

How are floating wind farms built

They are built on concrete blocks much heavier then the turbine itself. Most of the weight is located at the bottom, making the structure stable. Anchor chains attach these concrete blocks to the ocean floor. They are taller than normal wind turbines. Their blades are big, about the size of a football field. Big, tall blades extract maximum energy from the high winds.

Advantages of floating wind turbines

Wind turbines on land generate more electricity at night because wind speed increases over land at night. This energy cannot be used right away as it is the time of day when we turn off lights and go to bed.
Wind speed in the sea increases during later afternoons and evening. So, offshore wind turbines make high electricity during afternoons and evenings. This gives us electricity when we need it most. It is the same time when people turn on lights and heaters. If you look at a map that shows human population, you will see most populated cities and towns around coastlines. So, it is cost effective to build wind turbines in the sea, closer to densely populated human settlements.

Challenges of floating wind turbines

Many types of fishes use SONAR (sound vibrations) to navigate their way and communicate. Vibrations caused by wind turbines disrupt the SONAR waves. Studies show us marine life avoid wind farms and move to other areas.
Wear and tear of aging wind turbines pose the risk of micro plastics mixing with sea water. Maintenance and service of floating wind turbines require ships moving between the shore and the turbines, causing an increase in sea traffic and the resulting pollution.

Latest technology

Europe has the most offshore wind turbines. European countries are working on technologies that make them safe, cost-effective and eco-friendly. Air bubble curtains are circular tubes laid around the wind turbine. They give out air bubbles, making a bubble curtain around the wind turbines. It protects marine animals from sound vibrations made by the turbine.
Research work focussing on eco-friendly, anti-rust coatings are going on. We hope this research will lead to new products that make future wind turbines withstand salty conditions in the sea. It will increase life time of wind turbines and reduce micro plastics from old wind turbines mixing with the sea water.
Maintence work is done using drones. Real time monitoring with sensors notifies support staff on land about problems.

First and largest wind farms

The first floating wind farm Hywind Scotland was built by the UK in 2017. This wind farm has 5 wind turbines. It cam generate upto 30MW of electricity in one hour.
After Hywind Scotland, floating wind turbines have become bigger and taller. Today, the largest floating wind farm, Hywind Tampen is in Norway. It is built 140 km from shore, in the North Sea. With 11 wind turbines, it can make 88MW of electricity per hour. Electricity generated by this wind farm is not used to power homes. It is used to run deep sea oil and gas mines located in midsea, close to the wind farm. After it started working, this wind farm has saved 35% of fossil fuels used by the oil mines.

Haiyou Guanlan floating wind project is China's first floating wind farm. It can make upto 7.25 MW of electricity every hour.

Future plans of wind farms

The US is focusing on Offshore wind turbines. With its major cities located close to the sea and a long coastline, offshore wind turbines are the natural solution for green energy. The first full sized floating wind turbine is planned in the Gulf of Maine. It can make upto 15 MW of energy in 1 hour. This energy can power thousands of homes in NY city. It will be the first step in building a floating wind farm in the Gulf of Maine, with 10 such wind turbines that can together make 144 MW of clean energy.