When it comes to harvesting wind energy more efficiently, you don't need to reinvent the wheel — you just need to stick it in the ocean.
Swedish company Ehrnberg Solutions AB has developed the SeaTwirl, a new take on wind turbine technology. The system's unique design allows wind energy to be stored kinetically until it is needed, unlike many traditional turbines which require energy to be immediately fed into the grid. SeaTwirl's flywheel design also allows the system to generate energy even after the wind has died down.
Sticking out of the water like a carousel or merry-go-round is the top of the SeaTwirl's system. It's a vertical wind turbine with curved tines connected to a hollow torus ring.
Running through the center of the top carriage is the system's axel, which plunges below the surface of the water and threads through a cylindrical float assembly before connecting to the generator. The entire system is anchored to the sea floor and held in place with lines attached to the generator. Electricity is delivered ashore via seabed cables.
Yet the most innovative element to the SeaTwirl may be how the system incorporates water. When the wind is strong, the turbine's rapid spinning motion siphons water from the float assembly into the hollow torus ring. The water's added weight to the ring frame adds to the centrifugal force, which extends the turbine's spinning capacity, allowing the SeaTwirl to keep spinning after the wind has calmed.
The SeaTwirl's designers tested a prototype off the coast of Sweden last month and said it performed well. They believe their 1,411-foot, full-scale version could generate 39,000 megawatt-hours per year and store up to 25,000 kilowatt-hours. This would be enough to support 8,000 homes for one hour.
"Sea Twirl is a very exciting technological innovation with great potential. A feature that makes it especially interesting is its expected energy storage capacity which makes it possible to produce electricity even when the wind has slowed down, which has long been a challenge for wind turbines," said Dr. Peter Klason in an Ehrnberg Solutions AP press release. Klason is a physics professor and researcher at the SP Technical Research Institute in Sweden.