Small Wind Systems: Frequently Asked Questions

A small wind system converts the energy in the wind into electricity and is scaled to generate just enough power to meet the average on-site power demands of a home, farm or small business. Most small wind systems are net metered, which means that when the system generates more power than needed at that time, the excess is sent to the utility grid and the owner receives a credit from the electric utility. When the system is not producing enough power to meet demand, the electric utility supplies the remaining power.

There is no universally-accepted definition of small wind. Although some definitions make reference to the small size of a project, other definitions refer to “net metering with some excess sold back to the grid,” “noncommercial” or “not large utility-scale.” Energy Trust considers small wind to be systems, with a capacity of 100 kilowatts or less and a total extended height not exceeding 180 feet, that is compliant with all federal, state and local laws, codes and regulations.

Producing your own electricity from a renewable source could help protect you from future increases in electricity costs. In addition, there are many non-economic reasons for installing a wind system. The environmental benefits of renewable energy are immediate and long-term. A small wind system reduces demand for electricity generated from fossil fuels, and contributes to cleaner water, better air quality and to the sustainable use of natural resources.

The electricity produced by a small wind system depends on the wind resource and the size of the system. Depending on the size of the system and the wind resource, a small wind system will supply anywhere from 10 percent to100 percent of an average Oregon home’s yearly electricity usage. (On average, a four-person household uses 12,000 kWh annually.)

You can calculate your energy usage by looking at old electricity bills or by contacting your utility. If you use less energy, a greater percentage of your usage can be met with a wind system. Improving your home’s energy efficiency is the best way to reduce your energy use and get the most out of all your energy sources.

Small wind systems consist of a wind turbine mounted on a tower. There are three common types of towers: a freestanding monopole (like a street light), a lattice tower (like a radio tower) or a guyed monopole (like a street light with support cables from the tower to the ground).

freestanding monopole	lattice tower	guyed monopole

The footprint of the tower will vary from as small as nine square feet for a 60-foot, free-standing monopole to 21,600 square feet, including guy wires, for a 120-foot, guyed tilt-up tower.

In addition, an inverter, about the size of a large briefcase, will be mounted on a wall. The inverter can be mounted indoors near your breaker panel, or outdoors in a shaded location. A meter that measures the electricity generated by your small wind system will be installed near the inverter.

Not all locations are suitable for a small wind system, and many factors can influence the effectiveness of a specific system. Here are some ground rules:

• The annual average wind speed at the site must be at least 10 mph. You can check the estimated wind speed at your property using Energy Trust’s wind map.
• From wind resource maps, you can usually determine whether your property is a good candidate for further exploration. Wind resource at a micro-level can vary and you should consult a professional to evaluate the potential at your site.
• The property must be at least one acre.
• The tower must be at least 60 feet in height. (Tower height is the single most important factor in the economic success of a small wind system because a taller tower enables the turbine to access faster and less turbulent winds to produce more electricity.)
• To be eligible for an Energy Trust cash incentive, there are additional criteria and requirements.
• Wind turbines generate the most energy on high, open land where the winds are unimpeded by trees and buildings.
• Height limits, setbacks and other requirements vary in Oregon counties, so you or your contractor will need to check local zoning and permitting requirements. In general, wind systems are easiest to permit in rural areas.

You and your Energy Trust trade ally contractor will follow these steps. Your Energy Trust contractor will help you through the entire process and do much of the paper work.

Energy Trust does not provide incentives for homeowner-installed systems. However, homeowner installations may be eligible for Oregon energy tax credits. To qualify for Energy Trust incentives you must use an Energy Trust trade ally contractor.

To be eligible for an Energy Trust incentive, a small wind system must meet all siting requirements and use a turbine on our list of eligible turbines.

Many common concerns may actually be misconceptions resulting from confusion over the differences between large, utility-scale wind turbines and small wind turbines. For small wind systems, common concerns may include noise, birds and bats, setbacks, safety and lighting. Read more.

Yes, your wind turbine must receive regular maintenance to ensure that the system operates reliably. To do this, someone must either climb the tower, use a lift or the tower must be lowered.