Keeping a cap on the deployment and maintenance costs of offshore wind energy systems is the goal of T-Omega Wind, Inc. The developer targets a levelized cost of energy of about $50/MWh, which approaches that of fixed-bottom offshore wind energy structures.

Progress in reaching this goal is evident as the company has initiated real-world testing with a 1/16th scale prototype of its relatively lighter, shallow-draft offshore wind turbine following wave tank testing of a 1/60th scale model. These tests confirmed the design was capable of remaining upright even if a full-scale version was impacted by 30 m (98 ft) waves.

The prototype was recently launched off New Bedford, Massachusetts, showcasing the design that replaces the massive single-sided pinwheel generators of traditional offshore wind systems with a double-sided axle supported at both ends. Instead of a conventional single tower structure, four diagonal supports form a floating pyramid base anchored to the seabed with some slack. The arrangement allows the demonstrator to float around in response to changes in wind direction, passively orienting itself toward the wind.

Reduced material requirements and reliance on existing deployment infrastructure result in a lower cost wind turbine that is easier to install and unhook for towing to shore for maintenance. A full-size 10 MW turbine, weighing 1,200 metric tons to 1,800 metric tons, would include a 198 m (650 ft) rotor and variable pitch blades on a 119 m (390 ft) high pyramid with 70 m (230 ft) sides.

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