Home Wind Turbine Design What You Need To Know

Science Articles | February 26, 2009

When one thinks of a home wind turbine, what most probably comes to mind is a gigantic tower with jumbo-jet sized spinning blades. But, with everyone becoming more aware of conserving energy, the technology has advanced so much that it is now possible to have your own small-scale wind turbine at home.

When one thinks of a home wind turbine, what most probably comes tomind is a gigantic tower with jumbo-jet sized spinning blades. But,with everyone becoming more aware of conserving energy, the technologyhas advanced so much that it is now possible to have your ownsmall-scale wind turbine at home. Even better is the opportunity for usto make our own, without having to rely on the professionals.

So, how does a home wind turbine make power?

A home wind turbine makes power by spinning a generator. Thegenerator is attached to the rotor, made up of three aerodynamicblades, that is then attached to a tower. To keep the turbine facingthe wind, the rotor has a tail, that acts as a weather vain.

The generator is basically an electric motor. As the coils in themotor spin past the magnets, an electric current is produced. The powerproduced is stored in batteries, which are connected to an inverter tochange the direct current to alternating current, which can then beused to power your home. The advancement of motor efficiency, is thereason wind turbines have become so popular for home use.

Depending on your area's wind conditions, the tower can vary inlength. If you live near the sea where it is windy, the tower can beshorter, but in low-wind areas the tower needs to be taller to catch asmuch wind possible.

Over time the blades have improved drastically as researchersdeveloped lighter, stronger, more efficient blades, with the capabilityof turning even in the lightest breeze. Back in the day, wind turbineshad five blades, and looked similar to windmill water pumps, butrecently they have moved to three blades, taking the form of over-sizedairplane rotors. Like the tower, the blades vary in size, according toyour wind conditions and energy requirements.

While so far we have been explaining the typical horizontal axiswind turbine, there is another design that is starting to gainpopularity for small-scale projects. It is the vertical axis windturbine or VAWT. Very different to the standard horizontal axisturbine, the VAWT spins on a vertical axis, and almost looks like awaterwheel put on its side. Since the VAWT tends to operate low toground, it needs far more wind to make it turn efficiently, so it isnot the ideal option for homeowners or small businesses. The VAWT hasalso been accused by ecologists of interrupting and harming variousmigratory birds, making it less attractive for green enthusiasts.

Before going out and installing a wind turbine, it is best to ask yourself the following questions:

- How big is the property?

Wind turbines generally operate better in large areas that cover anacre. This is because wind flow is not deflected by any nearbybuildings.

- What is the average wind speed?

The recommended wind speed should be at least eleven miles per hour,but if that isn't the case then you may have to use a taller tower andlarger blades to catch higher altitude winds.

- What else can I use the wind turbine for?

If you could use the turbine for other purposes, such as pumping inwater from outside, then it may be useful than you think. This is thereason you see so many windmills scattered over farms - they help pumpwater from reservoirs to the farmhouse.

- Does my house need a constant power supply?

This is why so many people want to get a small wind turbine in thefirst place - to keep the house powered during blackouts, and preventeconomic losses. Although the wind turbine may not power the house allthe time, it's stored power can be used in emergencies, when theutilities are just not enough.

Answering these questions will give you a good idea of how muchpower you need, how big the tower a blades need to be, and how much itwould be worth investing to start making your own power at home.

The great thing about technology is that it is always improving. Somuch so that motors have become smaller, efficient and cheap enough forus to attach a few small turbines right on the roof, and produce thesame power as a larger turbine on a tall tower.

Although professional home wind turbines can run into severalthousands of dollars, it is possible to make your own for a tenth ofthe price, with components found at home and your local hardware store.Furthermore, the U.S. offers both state and federal tax credits thatyou can use to offset the installation cost. So not only will youreduce your electricity bill, but also your tax at the same time.