SheerWind claims its INVELOX wind turbine produces 600% more power

The idea behind the INVELOX system is to capture wind using wide mouthed funnels and channel it via ducts to a turbine sitting at ground level. The wind picks up speed as it is concentrated through a series of nozzle and pipes before it is delivered to a turbine, which produces electricity. SheerWind claims in its announcement that the system is capable of producing electricity with wind speeds as low as 1mph.

As an example, they say that tests have demonstrated that the system operating in natural wind speeds of 10mph is able to increase that speed to 40mph before it enters the turbine. After passing through the turbine, the wind is exhausted back into the environment, in this case, at 15mph.

NOTE: The claims from this company are dubious and no third-party has been allowed to test it, so take this with a grain of salt.

more http://phys.org/news/2013-05-sheerwind-invelox-turbine-power.html#jCp