Here we will discuss the Proven 7 (formerly Proven WT2500) as it is the wind turbine generator best suited to typical domestic use as it is just about able to power the electrical appliances in a standard 3-bed house without being too loud, large, or expensive. It is pictured below. Pictured above is the Proven 11 6kW model which can power a large house, but is not so suited asthetically for domestic use.
With a 3.5 metre diameter rotor, the Proven 7 wind turbine is available in 24 or 48 VDC, and 300 or 240 VAC versions and can generate 4,700 kWh of electricity per year with average wind speeds of 5 m/s on an ideal site. Proven wind turbines are downwind turbines.
Although the Proven wind turbines are more expensive than the vast majority of generators on the market, you are paying for reliability and durability. All turbines are marine quality built from galvanised steel, stainless steel, and plastics. The three blades are made from polypropylene, and the generator is a brushless, direct drive, permanent magnet generator. The absense of a gearbox reduces the noise output and servicing costs, increases reliability, and improves overall efficiency.
The 24V or 48V DC models can be used for battery charging, and the higher voltage AC models can be grid connected with a windy boy inverter to the grid, or to direct heating. The mast is self supporting therefore no guy ropes to trip over or wasted land, and the mast is of the tilt-up variety.
The Proven 7 has a cut in speed of 3.5 m/s (approx 8 mph). The generator and blades weigh in at almost 200kg and the tower is 241kg (6.5m) or 445kg (11m). Noise generation is not bad at 60 decibels in winds of 20 m/s, and this Proven wind turbine has no cut-out wind speed and a difficult to match survival wind speed of over 60 m/s (134 mph!).
The standard tower is 6.5 metres, however an additional £1400 will get you an upgraded 11 metre tower getting your wind turbine up into cleaner air and generating more power more often. A grid connected system will cost around £11,000 compared to a battery charging system at almost £16,000. If the turbine is to be used for heating only then the costs drop to just under £10,000. All prices exclude VAT. As always grants are available to reduce the total cost by up to £5,000.