Wind Power Generator
Powering homes is a breeze with wind turbines scaled for personal use.

Small wind turbines, mounted on towers between 80 and 120 feet tall, can generate electricity from the wind for home use. With on-site installations documented in at least 47 states, wind is a recognized renewable energy source for distributed generation of power on residential home sites. A wind-powered generator, or turbine, situated at the top of a high tower, has blades which spin to generate electricity. The electricity can either be used locally or sold to the utility company if an excess is generated.
In a typical residential application, the power from the wind turbine is connected to the main electric service wire to the home. Special interconnection equipment will allow powering the home, or sending the excess power generated by the turbine back to the utility grid. Otherwise, a distributed wind turbine can be designed as an “off-grid” type using batteries for storage of excess electricity. Many utilities credit the homeowner’s account for power produced by wind turbines that is fed back to the grid and require that special safety features be installed to assure the safety of line workers during power outages.
The amount of power generated by a wind turbine depends on the capacity of the turbine (rated in kilowatts, or kW) and the wind speed. Manufacturers will provide a power curve which shows the turbine’s output (in watts) at given wind speeds. For a typical home that uses 9,400 kilowatt hours (kWh) per year, a unit rated at between 5 and 15 kW will meet most of the home’s electricity needs.
Due to their height, wind turbines are best suited for remote or low-density residential lots of one acre or more. Developments that have adopted restrictive covenants may not allow wind turbines to be erected.
Installation
When considering a system, it is important to first check wind resource maps to determine the wind resource in your area. Next, local zoning, building codes, and neighborhood covenants should be reviewed, and any required permits or variances obtained. Supporting technical information can usually be obtained from the manufacturers. The most typical variance needed is for height restrictions—most towers will be between 80 and 100 feet tall.
For a grid-tied system, the local utility needs to be involved with setting up the interconnection. The complexity of this connection depends on the local regulations and the utility’s desire to streamline the process.
Determine where the tower will be placed—it should be at least 160 feet from a house or other structure. A concrete base is poured for the tower and anchoring is provided per manufacturer’s specifications. Light gauge towers require guy wires for stability while others are self-supporting.
To install the system, the tower and turbine are assembled and the turbine is wired and attached to the tower. Next, the tower is raised in place with a crane. After the tower is anchored and grounded, the turbine wiring is run from the tower to the main power service panel. Typically, a trench is dug for the wiring, although lines may be installed overhead. The electrical wiring must be sized to handle the maximum power output of the turbine.
An inverter is required to connect to the utility’s grid.
Benefits/Costs
Installed, a complete grid-interconnected, 10-kW wind turbine costs between $40,000 and $50,000 and will produce between 800 and 2,000 kWh per month (depending on the wind resource).
As a rule of thumb, wind power systems tend to be cost effective in areas in which the average wind speed is 10 mph or greater and utility costs are more than $0.10 per kWh.
There is some noise associated with the operation of the wind turbine; however, the noise level, described as similar to a washing machine, is not usually objectionable.

Solar Water Heaters
Systems that use the sun to heat either water or a heat-transfer fluid in collectors generally mounted on a roof

Harnessing energy from the sun to heat water is nothing new. Solar water heaters have been commercially available since the 1800s. What's new is how solar water heaters look these days. Most modern solar water heaters mount flush with a home's roof and resemble skylights. Solar water heaters are an environmentally sound way to reduce energy bills.
Solar energy can meet part or all of a home's domestic hot water needs. Geographic location, system design, collector orientation, and collector size will determine how much energy can be provided for domestic hot water heating.
Solar water heaters come in a variety of configurations. Each differs in design, cost, performance, and level of complexity. Most systems have back-up water heating such as electricity or gas. A solar water heating system usually consists of a hot water storage tank, a solar collector that absorbs solar energy, a back-up energy source, and (for forced circulation systems) a pump and controls.
There are two main types of systems: passive and forced circulation. Within each type, there are several configurations. A passive water heater consists of a water tank integrated into or located above a solar collector. In integrated collector storage (ICS) system, also called batch water heater, the water is heated and stored inside the collector. These systems are suitable only for warm climates where there is no risk of freezing. In a passive system where the storage is separate from the collector, as water in the collector warms, water flows by natural convection through the collector to the storage tank. A forced circulation system requires a pump to move water from the storage tank to the collector. Most solar water heaters in the United States are the forced circulation type.
There are several types of solar collectors. Most consist of a flat copper plate, painted black that has water tubes attached to the absorber plate. As solar energy falls on the copper plate and is absorbed, the energy is transferred to water flowing in the tubes. The absorber plate is mounted in a casing that has a clear covering and insulation to protect the absorber plate from heat loss. Other collectors include an integrated collector and storage system and the evacuated tube collector. Integral collector and storage systems combine the function of hot water storage and solar energy collection into one unit. Evacuated tube collectors produce higher temperature water and are more complex than flat plate collectors. Evacuated tube collectors consist of a series of tubes that contain a heat pipe to absorb solar energy and transfer it to a liquid medium. The tubes are evacuated (vacuum) so that there is very little heat loss from the tube. Most solar collectors are roof-mounted. Solar water heaters are used for domestic hot water, pool heating and space heating needs.
Installation
An experienced contractor should install solar water heating systems. Usually, a roof penetration is required.
Benefits/Costs
Solar water heaters save energy and use a renewable resource. By replacing electric energy or fossil fuel use for water heating, environmental carbon emissions associated with water heating are reduced or eliminated. A solar water heating system may result in immediate positive cash flow if the monthly cost of financing the system is less than the net savings. Some states have an incentive program to support the cost of installing renewable energy systems.