An Introduction to Wind Power Turbines

Overview


Lakota Wind Turbine installation with solar panelsWind turbine systems for homes are one of the more cost effective forms of generating electricity from a renewable energy source if you have the right site. In general terms, a site that has at least a half acre of open land and average of 10 mph (16km/h) or higher winds is a good candidate for a wind turbine installation.

It is possible to have a system which only gets it power from wind, however, many people combine getting power from a wind turbine with getting power from a solar electric system. The two technologies are often complimentary: when there's little sun (e.g. during the winter or when it's overcast), there's often more wind and vice versa.
 


How It Works


Whisper wind turbine on a farmJust like solar electric systems, wind powered systems can be used in two ways: off-grid or on-grid. Off-grid is when your home or business is entirely disconnected from electric utility company and you generate absolutely all of the electricity you need. Usually these systems costs about 30% more than a on-grid (or 'grid-tie' system). A grid tie wind power system sends all of its electricity back into the public electrical network (grid) which the electric company gives you credits for. At the month, the electric company sums up your credits with how much your home or business has consumed, and if you're lucky the electric company will owe you money! Unfortunately, most electric companies only pay you a small fraction of what they charge you for those extra kilowatt-hours you've created. So it's usually ideal to design a system that very closely offsets how much electricy you consume or just little less, than attempting to make money from the electric company.
 

 

Off-grid Wind Power System

A basic wind power system will consist of:

  • Wind turbine on top of a tower (1) that is wired down to a control box (2) that regulates the charging of a large deep cycle battery bank (3).
  • An inverter (4) which draws electricty from the battery bank and converts to normal household electricity (AC) and feeds the appliances in the home with power as needed.
  • Various safety devices like fuses, breakers and lightning arrestors (not shown in diagram).

 
Off-Grid Wind Turbine System: 1) wind turbine on a tower 2) wind turbine charge controlling system 3) battery bank to store a reserve of energy to be used by the home 4) inverter to convert battery electric to household power.

 

On-Grid (Grid-Tie) Wind Power

A grid-tie wind power system can have almost exactly the same components as the off-grid system except that inverter is a special inverter which connects directly into the public utility grid. Increasingly, there are also systems which don't use a battery bank at all - the electricity flows directly from the wind turbine into the special 'grid-tie' inverter and then into the grid. These batteryless grid-tie systems have the added advantages that they tend to be less expensive (no batteries to pay for) and more efficient (because the electricity doesn't have to pass through the battery bank first). On the downside, if there's a blackout then your wind turbine system will also shutdown and not be able to provide power to your home or business.

Simplified Diagram of a Grid-tie Wind Turbine System with Battery Backup for Home: 1) wind turbine on tower 2) wind turbine controller 3) battery bank 4) grid-tie inverter 5) utility meter to track how much energy is fed into the electric grid (6.).
 
Simplified Diagram of a Grid-tie Wind Turbine System (no battery backup): 1) wind turbine on tower 2) wind turbine controller 3) grid-tie inverter 4) utility meter to track how much energy is fed into the electric grid (5.).

 

 
How it works Wind generating sets