Floating wind power is precisely that - wind turbines on floating platforms at sea. As supposed to turbines anchored at depths up to only 60 meters, floating wind power turbines can be installed at a depth of 40 up to 1,000 meters. That’s why they can be placed out at sea, where the winds are stronger and more even.

By 2045, Sweden must reach net zero carbon dioxide emissions. At the same time the consumption of energy is estimated to rise by over 50 percent. As if that challenge isn’t enough, Sweden’s electricity production facilities are old and need to be updated or replaced. 100 TWh which is 70 percent of today’s electricity consumption needs to be replaced by 2040!

However, with 1,160 Swedish miles of coastline, (over 700 US miles) Sweden offers unique opportunities for highly effective wind power offshore with minimal environmental impact. Floating wind power off shore is the only renewable source of energy of the relevant magnitude to answer to the energy challenges which Sweden faces.

Based on the latest plans for the Gulf of Bothnia, the Baltic and the West Sea (February 2022), the Swedish government has asked The Swedish Energy Agency and other authorities to pinpoint suitable locations to enable production of another 90 TWh at sea, adding to the existing plans today. This would mean a total of 120 TWh of offshore electricity, which is almost equivalent to Sweden’s entire annual consumption of electricity.

The conditions out at sea are much more favorable than on land, as they offer stronger and more even winds. Also, it is possible to use higher turbines out at sea. One single sea based turbine can generate as much energy as three to four land turbines.

Offshore wind power parks bring minimal disturbance as they are placed far out at sea. It is not possible to hear them and they are usually not visible. Sometimes you can just about perceive them on the horizon.

Freja’s projects have been located to minimize the visual impact and the impact on the environment. The turbines are to be placed between 20 and 50 kilometers from the coast.

Under favorable conditions without mist or fog, the offshore wind power parks can be seen from land. The visibility varies depending on the distance, the weather conditions and the available light.

To be able to give an accurate image and perception of how visible our offshore wind power parks will be, we create visualizations, as part of our consultation documents and our descriptions of the environmental impact.

Read more about conditions and what affects visibility.

The sound from the turbines is often a source of concern. But how noisy is a wind power park really? To get an idea, it is useful to compare the noise with that of domestic gadgets. Below is an illustration of the sound from a turbine, presented by the turbine manufacturer GE. The visualization is based on data from NIDCD, which is part of the American National Institute of Health.

How loud is a wind turbine?

How loud is a wind turbine?

From a distance of 300 meters, a land-based wind turbine has a level of 43 decibels. This can be compared to the 50 decibels of an average air condition indoors or 40 decibels for most fridges.

From a distance of 500 meters, the level goes down to 38 decibels. In quieter areas, for example rural areas, background levels reach 30 decibels on average. On that level, it would not be possible to hear a wind turbine located 1.5 kilometers away.

From an acoustic point of view, water is hard, which means that sound waves are reflected and travel very efficiently across a surface of water. In other words, sound travels further across water than across land. For example, the sound from a 15 megawatts turbine can be heard at 35 decibels, from a distance of 300 meters on land. Across water, the same level would be audible from 2 kilometers.

Read more about measuring wind power noise here.

The offshore wind power parks will have an impact on the coastal areas in various ways:

• A connection to land through an underwater cable and cables connecting to the land based substation.

• An operation and maintenance base to serve the wind power park at sea.

• Increased traffic of goods during the installation phase.

The first two parts of the project are included in the planning process and are carried out to minimize the disturbance on land, at the same time as maximizing the potential to the local supply chain.

Every single activity in the marine environment has the potential of impacting seabirds and other marine wildlife. Offshore wind power on a large scale is still in the bud in Swedish waters, but there is more than 20 years’ experience from other European countries to learn from.

The projects are designed to minimize the impact on the marine environment and they align with international best practice, which has been established after years of observations, surveys and research. The projects undergo a complete environmental impact assessment. If there are any environmental risks, we carry out proven mitigation measures.

Studies show that wind power parks can act as artificial reefs and protected marine areas. This increases the amount of fish and seafood and in turn the access to prey.

No, the development of each project includes a specific archeological risk assessment with the support of geophysical investigation techniques to identify ship wrecks. When a shipwreck database has been established for a specific location, the project will be adapted to avoid any areas of archeological importance.

Currently, an offshore wind power park has a life expectancy of approx. 30 years, depending on the model as well as weather and sea conditions.

The power of the wind makes the rotor blades of the turbine rotate which creates large amounts of electricity. The electricity is then transmitted to land via an underwater cable. It can be used in households, for enterprises and transportation around the country, or even be exported abroad.

There are several types of technology available for floating turbines. The floating units are anchored to the bottom of the sea via mooring arrangements tied to several different anchor points. The mooring and anchoring system is designed to resist the impact of waves in the surrounding environment and keep the floating installation safely in place.

Concept for platform structure with anchoring
Example of a concept for platform structure with anchoring: barge, semi-submersible, mast buoy, TLP (Tension Leg Platform).

Anchoring concept
Example of an anchoring concept, from left: drag anchor, suction anchor, pile anchor, gravitation anchor and torpedo anchor.

Offshore wind power turbines are designed, built and run within the limits of extreme weather conditions. When the winds are very strong, the rotor blades can, for example, be slowed down to prevent a critically high speed of the rotor blades.

Sensors which are mounted at the top of the turbines, control the wind continuously. With very strong winds, the turbine can be turned off to protect it from damages. However, extreme weather conditions are rare in Sweden. Historical wind data along the Swedish coast, shows that theoretically wind power parks generate energy 90 percent of the time, based on satellite data.

We engage with local fishing communities at an early stage during each project, to ensure that the impact on fishing will be minimal. The parks are designed and established in a way to minimize their impact. Our priority is to avoid an interruption in the work of fishermen.

Offshore wind power parks create positive effects as they serve as rejuvenation surfaces for different species of fish. Studies show that several fish species increase in number close to the wind power parks. This is because the foundations of the turbines create a so-called rev-effect where the fish can find both food and protection.

We expect our projects to have great potential in creating local work opportunities within all phases of the project, and that they will also have an overall positive effect on the local community. Studies shows that offshore wind power can create 50,000 to 165,000 full-time jobs in Sweden between 2025 and 2050.

Most of the work opportunities will be created during the construction and operation phases of the projects. Large teams will be needed to serve the turbines on a daily basis. These work opportunities are long-term (up to 30 years); they are permanent and largely local.

Professional expertise needed includes dock workers, crane operators, ship operators (service and tugboats) as well as wind power and service technicians. Indirect work opportunities within areas such as transportation, food and accommodation will also be created.

We support recruiting locally, which includes collaborating with the fishing industry to explore the opportunities for future employment. We encourage local collaborations in our supply chain.

Studies shows that offshore wind power can create 1,500 to 4,000 full-time work opportunities in Sweden in 2030, and up to 10,000 in 2050. In total, offshore wind power is estimated to bring about 165,000 full-time work opportunities during the period 2025–2050, including both direct and indirect jobs within the domestic supply chain.

Access the study here.

We firmly believe in collaborating with local enterprises and will therefore actively encourage and prioritize local supply chains, when possible. Our philosophy is to develop and care for the local supply chains, through a strategy of a step-by-step springboard, where local suppliers and communities can grow alongside the phases of the projects. This springboard strategy will enable us to maximize the value of the projects for the local community.

Please do not hesitate to contact us here if you have further questions.