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It's always most efficient to use energy w/o conversion. First, identify your, major uses: area heat/cooling(HVAC), water heating, lighting, appliances, electronics, etc. My largest expense is electricity used primarily for computers & lighting. The first priority in most areas is insulation and drafts sealing--this is the fastest payback. If building new, or you have a very tight structure, look into heat recovery ventilation system (mandatory in Canada) these help ensured indoor air quality & help remove excess moisture. This should include making certain that windows don't allow large amounts of heat flow. Hot water heating via solar is cost-effective nearly everywhere--and as a pre-heat system it's even more widely useful. Payback on such systems can be under 3 years. At one time, 90%+ of hat water in LA was solar--until the gas companies gave away 'free' hot water heaters. System costs are competitive with efficient gas/electric equipment but lose the variable fuel costs. Solar area heating in new buildings can be a large percentage just through proper siting and window/roof overhang design. Ordinary windows on the ESW sides of buildings in most of NA will provide net heat gain--made even greater by proper use of heat-reflective glass and night insulation. Under-floor radiant hot water heat with zone control is optimal for new construction (ventilation must be handled separately,) underfloor systems can cool as well as heat. Efficient appliances are often hard to find or expensive (esp in the US) because few Americans are taught to look at life-cycle costs of purchases. The most efficient freezers and refrigerators are chest type. Either can be found commercially as drawer units, but are expensive. Deicing units cost nearly twice as much to run as manual defrosts. A small mid-range chest freezer can be easily converted to a refrigerator--often simply by adjusting the thermostat. Because freezers have more insulation, such conversions are very efficient (I fill the bottom with water jugs for emergency drinking water, to lift the refrigerated area to a more accessible height and to act as a thermal buffer (keeping a fridge full makes it more efficient, a thermal buffer helps deal with any power outages.) In any refrigerated or heated area, adding thermal storage mass will help make things more efficient by evening out temperature variations--always fill empty spaces in refrigerated areas with water jugs. Thermal mass of any sort inside the insulated shell of the building will help even out your heating & cooling costs--avoiding major temperature changes. Stone/concrete/brick/tile flooring and internal walls can add thermal mass and appearance. Thicker sheetrock also adds mostly invisible mass. Design or arrange to use as much natural light as possible. Reflecting light across the ceiling is a good way to get the light further in to the building, and helps keep the illumination levels even. Using as much solar in the form it arrives (heat & light) is most efficient--PV systems are 15-21% efficient and getting better--but heat or light use is 100% efficient. ventilation can be driven via a solar stack vent attached to the outflow of a heat exchanger--this pulls air through the building at no cost, and is controlled by adjusting airflow. Wind power is mechanical energy--as such it's most efficiently used to do things like pump water or move air. Conversion to electricity is less efficient, and the cost-effectiveness varies widely by location--adjacent lots may have very different pay-backs. Solar is similarly variable. But I've sen substantial heat recovery from very simple South wall air heat collectors at 41 degrees N Lat. You might want to give thought to your geography before investing. Coastal areas are already at increased risk of flood and storm surge, and the risk that low-lying coastal areas will be inundated by seawater within the next 15 years is substantial (the widely published 'estimates' of sea level change are extremely optimistic--note that every year new data comes out and the headlines read "Scientists were surprised by how much faster than expected _____ is happening." Areas at high risk include Florida, the Gulf Coast, the California Central Valley and coastal areas under 30' in elevation. 500/100 year flood zones should be avoided too. I recommend concrete & urethane foam structures for most areas, as they are very tight, very low-maintenance and very efficient. check out wwww.monolithic.com for more information. These structures are fire-proof, tornado-proof, and can be constructed partially or fully underground for more weather-resistant. They are FEMA-rated as 'hurricane-resistant,' FEMA's highest rating. And they can be constructed to be earthquake-proof. They may be built in any shape you can conceive, though avoiding external flat walls is a large factor in wind-resistance. I have no ties to Monolithic, I merely like extremely elegant and efficient design.

What is the actual output of this unit!? Thier site states they're feeding two 12VDC batteries....what with 6 watts at 12 Vdc in a 2mph wind. Then going though an inverter to increase it to 110 VAC.....what are the losses there. I would like to see a chart of the voltage output with and without a load, along with amperage. I've seen it running in low wind(no Load)but what happens when a load is placed on it? You can do a lot of "slight of hand" when stating performance without all the facts. Something tells me they are misleading us a bit with the "calculated" watts vs wind speed measurements.

Zee, I feel the same way until I can see some actual data from real world operating conditions.

@Rick, WRT no. 1, Read the full spec on the turbine. It includes a direction finding base. As several other people have pointed out, you need to factor in stimulus incentives and tax breaks. Whether or not it is "an expensive lawn ornament" depends entirely on where you are. If you're in an area that has little wind resources then yes, it's a lawn ornament. If, OTOH, you're in an area that has lots of wind resources available then it should work, and work well, if installed correctly. You are entirely correct in saying it should NOT be mounted on a roof! @Chris, I don't know how you'd calculate shaft losses or gear losses on this thing, since it doesn't have any.