Illustration of SeaTwirl's floating wind turbine placed at a fish farm. The turbine will be able to be combined with batteries and existing energy systems.

Could this blow away fish farm diesel costs?

A single wind turbine could in theory cut a Norwegian salmon producer's fuel bills by several million kroner a year. Now SeaTwirl is hunting for farmers.

Ole Andreas Drønen editor, kyst.no
Published

Swedish company SeaTwirl is looking to bring its floating, vertical-axis wind turbine into aquaculture. Initial talks with aquaculture companies in Norway are under way, and the company is working to establish a Norwegian supply chain.

SeaTwirl’s turbine has a nominal power of 200 kW and is designed for marine areas where grid connection is limited, expensive, or unavailable. It can be combined with batteries and existing diesel generators, among other things.

Kent Thoresen, Norway business developer at SeaTwirl.

Kent Thoresen at SeaTwirl tells Fish Farming Expert’s Norwegian sister site, Kyst.no, that the company is already in initial dialogue with a couple of Norwegian fish farming companies.

“They are very positive, and we are also working to establish a Norwegian supply chain. From the time a customer makes the decision to proceed, we expect it to take about a year for the turbine to be operational on site,” he says.

The company has also started a dialogue with Norwegian authorities about what permits are required to get started.

Can save 180,000 litres of diesel

According to Thoresen, the amount of electricity the turbine can produce will depend on wind conditions. SeaTwirl says it can produce up to 700 MWh per year at an average wind speed of 7.5 metres per second.

The company estimates that using diesel generators to produce the same amount of energy would require around 180,000 litres of diesel per year. With a diesel price of between NOK 20 and 25 (£1.58-£1.97) per litre, this corresponds to NOK 3.6 to 4.5 million in fuel costs, according to the company.

Unlike mains electricity, which is often just a third of the price that it is in the UK, the price of diesel in Norway is higher, especially as both land farmers and fish farmers in Scotland benefit from being able to use discounted red diesel, currently around £0.98 per litre if bought in bulk.

Thoresen emphasises that one turbine will not necessarily replace all diesel generated electricity.

SeaTwirl is proposing the use of floating wind power to reduce diesel consumption at Norwegian fish farming sites.

“It will vary with the energy demand at the location and the local wind conditions. It is also possible to install multiple turbines, and it is natural to combine them with battery storage. In this way, the solution can cover a significant part of the energy demand, and in some cases most of the need.

“We usually optimise towards the most cost-effective energy production, not necessarily replacing all diesel production.”

Estimated investment of 10–15 million

SeaTwirl estimates that a complete investment for most of the current projects will be around NOK 10 to NOK 15 million (£789,000-£1.18m).

“With good wind conditions, the payback period can be around five years. Early in the project, we conduct an assessment of the site so that we can calculate the expected energy production, diesel savings and economics more accurately,” says Thoresen.

Pros and cons of a vertical-axis turbine

A vertical-axis wind turbine has a main rotor shaft arranged vertically to the ground. Unlike standard horizontal turbines, its heavy parts like the generator sit at the base, and it captures wind from any direction without needing a turning mechanism.

It runs with very low noise, and takes up less space than a horizontal turbine but yields less total energy and faces heavy wear and tear on blades.

However, the calculations are indicative. Actual energy production and savings will depend on factors such as wind conditions, energy demand, battery configuration, and how the reserve power is used.

Tested in Sweden

Thoresen says that SeaTwirl has had a test turbine deployed in Sweden for around ten years. This was recently decommissioned after the test period ended.

One advantage the company highlights for aquaculture is that the turbine is floating and thus does not require permanent foundations on the seabed.

“This means that permanent foundations on the seabed are not needed, and the installation can be moved or removed if necessary,” says Thoresen.

SeaTwirl AB is a Swedish listed company that is now moving from development to commercialisation. In addition to Norway, the company is working on projects targeting the aquaculture industry in Chile and Canada, where the company has an agreement with Canadian start-up Aks Wind Energy Corporation to explore floating offshore wind opportunities in British Columbia.

“Norwegian aquaculture is a natural market for the technology. Norwegian fish farms have a significant energy need, while many locations are still dependent on diesel production. This makes local wind power combined with batteries particularly interesting,” says Thoresen.

 

 

renewable energy news floating wind turbines diesel reduction norwegian aquaculture seatwirl