You know you have enough wind available on your property to rid yourself of your dependence on the electric company. You’re ready to shop. Here’s the industry jargon you’ll need to know when you are talking to suppliers and contractors.
Swept Area: This is the area the generator blades will sweep. Ths swept area coupled with your average wind speed will determine your total energy output. The swept area can be calculated from the rotor diameter.
Tower Top Weight:The weight of the wind generator which will be mounted on top of the tower. This weight will determine your choice of tower. Heavier generators which are usually better builds and more durable will require a beefier tower.
RPM (Revolutions Per Minute): This is the speed at which you can expect the turbine to turn at a given wind speed. Paradoxically you don’t necessarily want a high number here because slower RPM generators will typically last longer and run quieter. Since the alternator is matched to the RPM to ensure best energy output for the given speed a high RPM does not ensure high output.
Annual Energy Output: These are general numbers of what you can reasonably expect from a turbine at a given wind speed. Though they are helpful there are too many variables from site to site for them to be accurate for your specific site. Use them as a guide in comparing one turbine to another. It’s best to err on the side of caution and buy the unit that will give you somewhat more output than you are anticipating you’ll need.
There are other terms you’ll learn but these will get you started on your quest for the perfect wind generator to suit your needs. One term you shouldn’t pay attention to, according to Ian Woofenden, is rated or peak power which he says is a meaningless marketing ploy.
The total cost of your system will include the wind generator itself, the batteries, the tower, the inverter, and any costs you incur in installation and permits needed. Keep in mind that the cost of the other items can easily exceed the cost of the wind generator itself.
The controls for your wind power system are also important. Some wind generators include them as part of a package while some don’t because there are different needs for grid tied systems as opposed to off the grid systems. Make sure when comparing system prices that you’ve taken into account all the components you’ll need for any particular system.
The most important consideration is installation. Working with electrical systems can be a tricky and potentially deadly business. This is the one cost you don’t want to skimp. If you don’t have a good grounding in working with electrical systems it’s best to hire a contractor to help with this part of the installation. The height and weight of a wind system increases this challenge.