http://www.provenenergy.co.uk/proven_energy_news0030.php

LIVIN’ LARGER WITH SMALL WIND
Like all other wind energy projects, the key to success with small wind turbines is location.
Generally, the more interference there is to wind flow, the less electricity a small turbine generates. That’s why authorities discourage installing small turbines (100-to-500 watt capacities to 2.5-to-50 kilowatt capacities) in urban environments. But there are exceptions.

Alex Murley, Small Systems Manager, British Wind Energy Association (BWEA): "We need to be wary of generalizations…If you put a turbine on a high-rise building above all the wind turbulence it will perform very well."

Small turbine energy return is primarily proportional to size: A 1-kW turbine will generate 10-to-20% of annual energy use. At average wind speed (6.5 meters/second), an average UK house using 3300 kW-hrs/year (a utility bill of £500), a 1-kW turbine earns £50-to-£100/year and at a cost of £1500 pays itself off in 15-to-30 years.

A larger, £22,000 Proven Energy 6-kW turbine generates 12,500 kW-hrs/year and earns better returns so has a shorter pay off.

Returns from selling unused electricity to the grid via a feed-in tariff or from selling Renewable Energy Credits (RECs) for cutting emissions earns more money and can shorten the pay off period to 10 years.

A still-larger Gaia-Wind 11-kW turbine costs £35,000 ($65,000), produces 40,000 kW-hrs/year and, with the feed-in and RECs, can pay off in 5 years.
BWEA: "At the right locations…small wind systems can produce electricity cheaper than the grid and payback their embedded carbon within months."

Remember: Wind speeds vary, thereby varying pay offs. And it is not only the speed of the wind that matters.

Lynda Garman, technical sales executive, small turbine supplier Proven Energy: "The swept area [the area through which the blades turn] is very important to the function of a wind turbine. If you put a small turbine in a turbulent area it will not work efficiently."

These variations make picking the right location challenging. There has been some adverse publicity for small wind turbines recently, based on the hard numbers from the smaller, urban projects. It is true the numbers are not readily favorable at present, but that will not likely be true for much longer.

Alex Murley, BWEA:"As the cost of energy goes up and up and technology costs come down, even the smaller micro turbines will be very interesting opportunities to save money and carbon…"

One of the first important changes in the cost-benefit analysis for small wind in the UK is the pending feed-in tariff. Anticipating that the government will follow other European governments and institute a guaranteed rate of return over a long period of time, small wind installation jumped 80% from 2006 to 2007 and will likely double from 2007 to 2008.

Original article and credit goes to:

newenergynews.blogspot.com

For media and press enquiries only, please