London-based manufacturer Poduhvat has developed a wind turbine which they claim can produce five times more energy than traditional wind turbines with the same rotor size. The contra-rotating Whetar turbine is almost completely silent and it can generate 43,8 MW/h per year with under 50% load capacity.
The turbine has two double contra-rotating rotors encased with specially constructed housing duct. The rotors cancel each other’s rotational forces, which significantly reduces vibrations and makes the turbine more suitable for urban areas. The ducted part of the turbine creates a ring-like area of high pressure around the turbine, leaving the area of lower pressure behind. This works as a funnel sucking air into the turbine. The low speed air accelerates and is used by two contra-rotating rotors which additionally accelerate each other.
The expected energy production depends on the site’s prevailing winds but the company claims that the turbine can produce 43,8 MW/h annually, under 50% of load capacity. The turbine, with smaller-sized rotors compared to the conventional rotor models of the same category and practically no noise, can be mounted at lighting poles and building roofs.