Steve Willey

We started our home power system and our home energy business with small scale wind electric wind generators, simply because solar was not quite available in 1974. We are located on a hilltop with no water power or other electrical source. Our wind is not particularly good here, in fact in late summer there is NO wind for many weeks at a time. Never the less, as our only option, any help from the wind seemed better than running an engine generator. The only wind electric generating systems considered were those designed to charge a 12 volt battery since storage was necessary in our stand alone system, 2 miles from the powerlines, and we already had a generator charged battery system.

Now that photovoltaics technology is available almost anywhere, windmills are seldom used in this mountainous area with so few good windsites. We get almost all our power from photovoltaics. Still the windmills will stay in service atop their 45 foot roof platform. They are a real pleasure to see and they fill a complimentary role WORKING WITH THE SOLAR. If we have a dark stormy day, it's usually windy. A mixed source produces power in more varied conditions, which means more evenly distributed power than is possible from a single source.

Site Selection and Windspeed

When there is a question of possible wind resources on a site, I recommend starting with photovoltaics, but less wattage than is planned for the finished system size. This can be used for immediate power needs while the wind is carefully analysed for the next full year. At the end of that time you will know whether to add a windmill or more solar. It is a costly mistake to install a wind machine only to find your wind is not adequate.

I made a simple device to measure windspeed for 6 months prior to buying a windmill. The device was a giant anemometer made from three plastic toilet tank floats cut in half to form cups. A magnet attached to the wheel activated a magnetic reed switch which was connected to the "=" key of a pocket calculator. Most calculators can be made to count revolutions this way. At any windspeed, 230 revolutions represented a mile of wind passing, so each night it's easy to divide the days mileage count by 24 (right on the same calculator) to get average miles per hour windspeed. Actually such averaged windspeed can be misleading. Most windmills start generating in winds OVER 8 miles per hour. An average 7 mile per hour wind measured can represent no power if it's 7 mph all day, or the same can generate substantial power if it's 14 mph for 12 hours and 0 for the next 12. Windspeed should be read several times a day to show true hours of each windspeed. Write the readings on a calendar. This data allowed me to select the machine that would meet my electrical needs from the available wind. In the early 70's there were lots of windmills available, almost all of which are now gone! The one I selected happened to be a WINCHARGER, a 40 year old design that is still being produced in one model.

Location

Wind turbine location is very important. If you don't have a good view of the direction of incoming wind, AND DOWNWIND TOO, your wind may be turbulent. A weather vane that changes direction more than 90 degrees most of the time is a sign the wind may not be steady enough.

Here in the forest, it is necessary to get the windmill up above the tree height. The rule is at least 15 feet higher than anything else for 500 feet around or most of the wind will miss the generator. But watch out, your forest will grow taller about one foot a year, and your tower won't grow an inch. Plan ahead.

Triangular metal antenna towers by Rohn are a neat solution, but these towers can cost more then the windmill. Another neat solution is to mount the mill on a wood pole tower. Poles require at least 3 heavy guy wires and a welded bracket made to match the generator to the pole top. To take this another step, we used 4 poles to build an enclosed tower 10 feet square and 46 feet high, on top of which are the metal 10 and 20 foot windmill tower stubs. Later we built the house right on as an "addition" to the tower. This provided three extra rooms off the house and a porch. Now the tower platform serves to mount our solar modules as well.

When windmills are mounted on a house, out of balance blade vibration can be transmitted through the whole house. If the blade is balanced well, vibration is not objectionable. If not kept in balance, the occupants of the house have to look at their meter panel to see if the vibrations and rattles are in earthquake tremor or just the windmill spinning! We have had some strange comments from overnight guests who aren't warned.

Wiring

Wire length and size is critical on 12 volt wind units. Generally 200 feet is the maximum practical distance to run cables for a 450 watt (35 ampere) wind electric generator. Connection to the battery is independent of all other charging sources. The charge to the battery is the sum of the wind generator & any other source connected.

Steve and Elizabeth Willey's home in Sandpoint, Idaho.

Windmills must be mounted high in the open, which is also an ideal position for lightning attacks. Ours are hit regularly in spring and summer storms. The chassis of each is wired directly to the metal well casing below the tower and so far this has prevented all but minor damage to equipment in the house. More lightning damage comes in via phone line than from the windmill.

Maintenance

These smaller machines that I have are surprisingly durable. The only maintenance has been refinishing the wooden propellers every few years (or else you will have to replace it at $100. a shot). Occasional rebalancing of the blade is needed. The only parts replaced in 14 years have been one propeller, (and the old one went on to be used elsewhere), plus a couple of $5. items like brushes or a wind-direction turntable bearing.

Availability

Today there are few windmills on the market. In the $1000 or less range there there are two that give good performance. The 450 watt Wincharger is still available, with a metered regulator panel ready to connect to your battery. The famous 200 watt Wincharger has just been disconnected, but a few may be on the market still (and I have a used one on consignment here). A new company in Arizona, SOUTHWEST WINDPOWER has just introduced a 250 watt unit for $795 which will replace the discontinued 200 watt Wincharger. Smaller wattage machines I have seen are best suited for small trickle charging of batteries on boats, rather than supplying the wattage needed for a home power system, and cost is close to those listed above.

Steve and Elizabeth Willey own and operate Backwoods Solar Electric. You can write them at 8530 Rapid Lightening Creek Road, Sandpoint, ID 83864, or telephone 208-263-4290.

Renewable Energy Eco Friendly

Renewable Energy Eco Friendly

Renewable energy is energy that is generated from sunlight, rain, tides, geothermal heat and wind. These sources are naturally and constantly replenished, which is why they are deemed as renewable.

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