Booklet series explains consumer benefits of small wind turbines

GOLDEN, Colorado, US, April 11, 2007.

A U.S. agency is developing consumer guides for small wind electric systems, to cover each state in the country.

“Wind energy systems are one of the most cost-effective home-based renewable energy systems,” explains the National Renewable Energy Laboratory in a series of booklets, ‘Small Wind Electric Systems: A U.S. Consumer’s Guide.’

“Small wind electric systems can make a significant contribution to our nation’s energy needs.”

Wind turbines which can generate a “significant portion” of the electricity needed by the average home generally require at least one acre of property, and 21 million homes in the U.S. are built on such sites. One-quarter of the U.S. population lives in rural areas, and the documents explain that “small wind energy system can lower your electricity bill by 50% to 90%, help you avoid the high costs of extending utility power lines to remote locations, prevent power interruptions, and it is non-polluting.”

A small wind electric system will work if there is sufficient wind and if tall towers are allowed in the area.

“Before choosing a wind system for your home, you should consider reducing your energy consumption by making your home or business more energy efficient. Reducing your energy consumption will significantly lower your utility bills and will reduce the size of the home-based renewable energy system you need.”

“The largest portion of a utility bill for a typical house is for heating and cooling,” and insulating and upgrading heating and cooling systems will have the largest impact on residential energy costs, it explains.

“A small wind energy system can provide you with a practical and economical source of electricity if

• your property has a good wind resource;
• your home or business is located on at least one acre of land in a rural area;
• your local zoning codes or covenants allow wind turbines;
• your average electricity bills are $150 per month or more;
• your property is in a remote location without easy access to utility lines;
• and you are comfortable with long-term investments.

” Before investing in a wind turbine, the document warns of potential obstacles.

“In addition to zoning issues, your neighbours might object to a wind machine that blocks their view, or they might be concerned about noise. Most zoning and aesthetic concerns can be addressed by supplying objective data.”

The ambient noise level of most modern residential wind turbines is 52 to 55 decibels, which means that “while the sound of the wind turbine can be picked out of surrounding noise if a conscious effort is made to hear it, a residential-sized wind turbine is no noisier than your average refrigerator.”

A typical home uses 10,000 kWh of electricity per year so, depending on average wind speed, a turbine rated in the range of 5 to 15 kW would be required to make a significant contribution to this demand.

“Mounting turbines on rooftops is not recommended; all wind turbines vibrate and transmit the vibration to the structure on which they are mounted,” it warns. “This can lead to noise and structural problems with the building, and the rooftop can cause excessive turbulence that can shorten the life of the turbine.”

“Grid-connected systems can be practical if the following conditions exist:

• you live in an area with average annual wind speed of at least 10 mph (4.5 m/s);
• utility-supplied electricity is expensive in your area (about 10 to 15 cents per kWh);
• the utility’s requirements for connecting your system to its grid are not prohibitively expensive;
• and there are good incentives for the sale of excess electricity or for the purchase of wind turbines,

“If your wind turbine is connected to the local utility grid so that any of the power produced by your wind turbine is delivered to the grid, then your utility also has legitimate concerns about safety and power quality that need to be addressed.” Some utilities require small turbine owners to maintain liability insurance in amounts of US$1 million or more but, “in the 21 years since utilities have been required to allow small wind systems to interconnect with the grid, there has never been a liability claim, let alone a monetary award, relating to electrical safety,” it notes.

In seven states, laws or regulatory authorities prohibit utilities from imposing any insurance requirements on small wind systems that qualify for ‘net metering.’