Innovation That Matters

SeaTwirl is developing offshore vertical axis turbines | Photo source SeaTwirl

Floating vertical axis wind turbines

Agriculture & Energy

A new wind turbine design could make offshore wind more efficient and even cheaper

Spotted: For countries with a large coastline, offshore wind has the potential to deliver a huge amount of sustainable energy. In the UK alone, electricity generation from wind power increased by 715 per cent from 2009 to 2020. Yet, many offshore turbines are designed to replicate onshore turbines, which are not cost-effective and do not take full advantage of the unique environment the ocean provides.  

Now, Swedish company SeaTwirl is changing all that with floating vertical axis wind turbines (VAWTs) that have been proven to withstand hurricane-force wind and wave conditions. Unlike the conventional horizontal axis wind turbines (HAWTs), which look like a windmill, VAWTs are more like a spinning cylinder. SeaTwirl’s design uses three blades mounted on a pole. This structure sits inside a static generator ring, which is anchored to the sea floor. The entire pole spins, and the generator harvests energy to send back to shore by cable.

SeaTwirl claims this design is not only cheaper, but also more efficient, as it can use wind coming from any direction. Additionally, the VAWTs can run their generators at or below the waterline, eliminating the need for strong towers and huge counterweights below the surface – significantly reducing materials and costs. The VAWTs can also be placed much closer together than HAWTs, increasing yield per area.

While the company has been running a small, 30-kilowatt test version of its VAWT, called the S1, off the coast Sweden since 2015, it is now preparing to build a 1-megawatt version, the S2. The company has recently partnered with energy and maritime supplier Westcon to build and deploy the first S2 off the Norwegan coast.

Wind and ocean power is increasingly being seen as a game changer in the renewables space. Springwise has seen the pace of both investments and innovations pick up, with developments such as a deep-sea turbine that generates power from ocean currents and a two-bladed floating turbine.

Written By: Lisa Magloff



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