Stand-alone or grid-connected system?
Small-scale wind power is particularly suitable for remote off-grid locations where conventional methods of supply are expensive or impractical. Most small wind turbines generate direct current (DC) electricity. Off-grid systems require battery storage and an inverter to convert DC electricity to AC (alternating current - mains electricity).

You also need a controller to divert power to another useful source (e.g. space and/or water heaters) when the battery is fully charged.

It's common to combine this system with a diesel generator for use during periods of low wind speeds. A combined wind and diesel system gives greater efficiency and flexibility than a diesel only system. It allows the generator to be used at optimum load for short periods of time to charge batteries when there is little wind, rather than by constant use at varying loads.

Wind systems can also be installed where there is a grid connection. A special inverter and controller converts DC electricity to AC at a quality and standard acceptable to the grid. No battery storage is required. Any unused or excess electricity can be exported to the grid and sold to the local electricity supply company.

Connecting a residential wind turbine to an electrical grid allows homeowners to produce their own electricity but still have access to electricity even when the wind isn't blowing. This option eliminates the need for batteries by allowing a homeowner to use energy from the grid when not enough energy is provided by the wind turbine. It also allows homeowners to sell excess energy back to the utility. The technical and economic issues of connecting to the grid varies depend on the state and utility's policy. According to the Michigan Wind Energy System Sitting Guidelines Draft #5 the rules for connecting a residential wind turbine to the grid are as follows:

"Utility Notification and Interconnection: No small wind energy system shall be installed until evidence has been given to the local government that the utility company has been informed of the customer's intent to install an interconnected customer-owned generator. An interconnected customer-owned generator shall comply with Michigan Public Service Commission and utility requirements. Off-grid systems shall be exempt from this requirement."

There are 4 components to most grid-tie systems: the wind turbines, the tower, the Whisper Link™ controller, and the power inverter. In addition, optional items such as battery banks and remote controls are also available.