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Wind power is one of the most basic sources of energy found on Earth. Like most forms of renewable energy, it is created by the Sun, in this case, a thermo-dynamic effect of solar radiation striking the atmosphere, land and bodies of water. Like solar thermal energy, wind power is easily put to use, as when harnessed for its mechanical force to push a sail or turn a windmill. The main focus today is of course, turning wind power into electricity, and most of what we read about has to do with large, utility-scale wind farms with multiple megawatt turbines sending power over high-tension transmission lines to distant urban centers. Though this scale of “big” wind power has received the most attention, there is increasing interest in medium and small turbines sized to agricultural, commercial and residential applications.
Residential size turbines are what we call “small wind,” and are intended to partially or completely offset a typical household’s annual electricity usage. Like PV (photovoltaic, solar-electric) systems, the power output for a given system is directly related to the available energy to capture and convert into electricity. Wind resources vary dramatically by region, and also in the immediate area depending on topography, foliage, nearby man-made structures, etc. Generally speaking, the best wind resource in New Mexico is found up and down the eastern side of the state where the plains allow wind forces to build and develop a mostly lateral, non-turbulent flow. But there are many areas in central and north-central NM where wind is funneled and concentrated by mountain passes and broad valleys into a very usable resource, often averaging 10 mph or more on an annual basis.
With a 10 mph average wind resource, a small 1.8kw turbine mounted on a 33’ tower can generate around 230 kwh (kilowatt hours) per month, which is a little over 1/3rd of an average New Mexican household’s usage. Systems that size install for roughly $14,000 and have an output comparable to a 1.8kw PV system, which would install for perhaps $20,000.
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However, since wind power systems do not currently qualify for the 30% State and Federal renewable energy system tax credits, a PV system with the same annual output actually costs about the same to install after those credits are figured in. Where wind power really takes off in terms of output and payback, is with larger turbines or stronger wind resources.
For example, the same turbine with a 15 mph resource will produce over 500 kwh/month, the same as a 3.9kw PV  system installing for about $28,000 after Federal and State tax credits are applied. At that point, the wind power system produces the same output for about half the installed cost of PV. But even with a wind resource of 10 mph, a small wind turbine can be quite useful in an off-grid installation where the combination of wind and PV work together to provide more consistent power day and night, rain or shine. Another aspect of renewable energy systems where small turbines attract some buyers is their visible appeal as icons of the western experience, but with the added benefit of advanced engineering, they can be very quiet and have a service life of 25 years or more.
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