Long relegated to the margins of the wind turbine industry, vertical axis wind turbine ( VAWT ) could get a new lease of life on floating platforms.
The patent, also approved recently the U.S. according to SeaTwirl, is for a design that would allow the generator and bearing housing to be replaced just above the water surface by boat, cutting the cost of installation and maintenance and minimizing downtime.
Most of the delicate equipment in standard horizontal-axis offshore wind turbines is high above the water, making repairs more difficult and dangerous.
SeaTwirl’s spate of announcements comes after research by the U.S.-based Sandia National Laboratories last year found there could be significant potential for VAWTs to cut the cost of offshore wind on floating platforms.
The five-year, $4.1 million study found VAWTs could potentially slash the cost of floating offshore wind turbines, installation and maintenance by doing away with the need for gearboxes, high-speed shafts, yaw systems and nacelles, which are all subject to faults.
But the main attraction of VAWTs compared to horizontal-axis wind turbines (HAWTs) in an offshore context is that they could potentially work with cheaper floating platforms.
“For floating offshore wind, the platform is the single largest contributor to the levelized cost of electricity,” research lead Dr. Brandon Ennis.
“If you have a slightly more expensive rotor but a platform cost that is substantially reduced, that could be a system benefit.”
Although still in its infancy, floating offshore wind is expected to take off in the 2020s as its costs come down and many of the best sites for offshore wind farms in shallower waters are used up.