HOME TRENDS

If there is one thing that Barack Obama and Al Gore have brought to the forefront of mainstream media in recent months, it is that the so-called "green movement" is about to start moving again. With the announcement of the Cap-and-Trade Bill (H.R. 2454), homeowners are waking up to the possibility of an increase in energy prices. Whether this happens or not, homeowners have begun to take a new interest in wind-power to generate their own energy and hopefully save a few bucks. Though this may sound like a good idea on the surface, our investigation has provided some pertinent facts that homeowners should know before jumping head-first into deploying a wind-powered alternative energy solution.

Wind-Turbine Costs

While homeowners are thinking about how much they will save by using wind energy, they should not forget about how much they will have to initially spend. Wind turbine kits range in cost from $400 to over $5,000 depending on how much electricity they can produce. As you would expect, the cheaper turbine kits produce less electricity (about enough to power a small room) while larger turbines can fulfill half of an average household's electicity needs. Regardless of how much energy a wind turbine generates, recoupment of your initial investment will take three to five years based on current energy costs.

Aesthetics and Footprint

Imagine a tranquil neighborhood of higher-end homes, a babbling brook nearby, richly-painted porches, and one of those homes sporting a wind turbine tower extending upward from beside the garage that rivals most HAM Radio operator antennas. Now, imagine the support cables radiating from tower and connecting to every solid object within a sixty-foot diameter from the tower's center-mass. Though not every wind turbine tower evokes such industrial imagery, the aforementioned is certainly an accurate depiction of your average high-output turbine tower's footprint. Not only are larger, high-wattage towers a nightmare for Homeowner Associations, they are generally unsightly to most residents in a neighborhood setting and may, in fact, violate certain residential codes if installed without a permit.

Fortunately, there are much smaller and more-attractive alternatives that neighborhood-bound homeowners can install. Though these smaller turbine units cannot generate the same electrical output as their larger cousins, they also won't attract any negative attention. In fact, there is a certain "cool factor" to the design of many of the smaller turbines ~ so-much-so that having one may just start a neighborhood trend.

Power Generation (from AWEA.org)

How much electricity can one wind turbine generate?

The ability to generate electricity is measured in watts. Watts are very small units, so the terms kilowatt (kW, 1,000 watts), megawatt (MW, 1 million watts), and gigawatt (pronounced "jig-a-watt," GW, 1 billion watts) are most commonly used to describe the capacity of generating units like wind turbines or other power plants.

Electricity production and consumption are most commonly measured in kilowatt-hours (kWh). A kilowatt-hour means one kilowatt (1,000 watts) of electricity produced or consumed for one hour. One 50-watt light bulb left on for 20 hours consumes one kilowatt-hour of electricity (50 watts x 20 hours = 1,000 watt-hours = 1 kilowatt-hour).

The output of a wind turbine depends on the turbine's size and the wind's speed through the rotor. Wind turbines being manufactured now have power ratings ranging from 250 watts to 5 megawatts (MW).

Example: A 10-kW wind turbine can generate about 10,000 kWh annually at a site with wind speeds averaging 12 miles per hour, or about enough to power a typical household. A 5-MW turbine can produce more than 15 million kWh in a year--enough to power more than 1,400 households. The average U.S. household consumes about 10,000 kWh of electricity each year.

Example: A 250-kW turbine installed at the elementary school in Spirit Lake, Iowa, provides an average of 350,000 kWh of electricity per year, more than is necessary for the 53,000-square-foot school. Excess electricity fed into the local utility system earned the school $25,000 in its first five years of operation. The school uses electricity from the utility at times when the wind does not blow. This project has been so successful that the Spirit Lake school district has since installed a second turbine with a capacity of 750 kW. (For further information on this project, see at the Web site of the International Council for Local Environmental Initiatives.)

Wind speed is a crucial element in projecting turbine performance, and a site's wind speed is measured through wind resource assessment prior to a wind system's construction. Generally, an annual average wind speed greater than four meters per second (m/s) (9 mph) is required for small wind electric turbines (less wind is required for water-pumping operations). Utility-scale wind power plants require minimum average wind speeds of 6 m/s (13 mph).

The power available in the wind is proportional to the cube of its speed, which means that doubling the wind speed increases the available power by a factor of eight. Thus, a turbine operating at a site with an average wind speed of 12 mph could in theory generate about 33% more electricity than one at an 11-mph site, because the cube of 12 (1,768) is 33% larger than the cube of 11 (1,331). (In the real world, the turbine will not produce quite that much more electricity, but it will still generate much more than the 9% difference in wind speed.) The important thing to understand is that what seems like a small difference in wind speed can mean a large difference in available energy and in electricity produced, and therefore, a large difference in the cost of the electricity generated. Also, there is little energy to be harvested at very low wind speeds (6-mph winds contain less than one-eighth the energy of 12-mph winds).

In Conclusion

There is no doubt that generating your own power is a smart idea since none of us can control what power companies, municipalities, and federal agencies will do to future energy prices. Even if you can afford your own wind turbine, the best practice to keep you energy costs low is simply to consumer less electricity to begin with. Turn off lights that aren't being used, open some windows for natural sunlight and fresh air, and even consider installing a security skylight to help light and heat your home naturally. By doing this, wind-power begins to make even more sense.

Let's just keep our fingers crossed that homeowners will not get taxed (or surcharged) any time soon for not using enough electricity.