Submission Suggestions

LOCATION OF SITE

My wife Beverly and I live on the western edge of the Colville Indian Reservation in North Central Washington. Our 80 acres lies on the top of a plateau (elev. 2600 feet) with little, but barbed wire to stop the wind. In addition to the wind, we have good solar potential with an average of 4.1 sun hours per day. We have no hydro power potential.

I started thinking seriously about alternative energy around 1965, and moved slowly in that direction until, finally, our home is 100% powered by alternative energy. I looked, briefly into bringing power lines in, but with costs in the neighborhood of $20,000, we figured that we could build a system for less. Paying for access to a power line would give us the privilege of paying a monthly power bill for the rest of our lives. This high cost was our excuse to do what we wanted to do in the first place and that was to produce all of our own power.

Windpower System

Our primary source of power is a Bergey BWC-1000 windplant which feeds 20 each 6 volt, 250 ampere-hour lead acid, deep cycle golf cart batteries, wired in series to deliver 120 volts DC. This power is used almost exclusively for home lighting, and is an improvement over the kerosene lamps of two years ago. We have a Kohler 110 volt generator for backup but rarely use it, due to the frequent winds. Integrating the 110 volt generator into our 120 volt system required only a slight increase in engine RPM to boost the voltage to within operating limits. One thing to watch for when buying one of the numerous old Kohlers which can be found lying around, is to be sure the generator produces the type of power you need. Kohler built both AC and DC generators and the difference is not readily apparent. The quickest way to tell if it's AC or DC, is to examine the generator section of the unit. If it is DC, it will have 4 field coils, if it is AC, it will have 6 field coils.

The old Kohlers are very durable, since they are built of cast iron and turn only 1,000 to 1,200 RPM. I found ours in the back of an old garage and the owner was glad to take the $250 that I offered to get it out of the way.

The heart of our system, the Bergey BWC-1000, is an up wind, horizontal axis windplant which uses propeller blades that are rigidly attached to the alternator can, but are free to twist about their longitudinal axis. A pitch weight projects forward from the leading edge of each blade. As the RPM increases, the weight tends to twist the fiber glass blade toward a lower pitch angle, thereby improving aerodynamic performance. Bergey employs, what they call an Autofurlâ„¢ tail assembly which automatically turns the machine out of the wind, when speed exceeds 32 MPH. In one 23 1/2 hour period, we had average wind speeds of 76 1/2 MPH, with violent gusting, but the BWC-1000 handled it.

The brain of the system is the EMS-4 controller. This unit

The Bergey in its element protects the battery storage system from overcharging or excessive discharge. If the batteries are fully charged, the EMS-4 will automatically divert the power to an alternate load. 5 colored lights on the front of the EMS-4 tell, at a glance, what mode the system is in. Rocker switches allow override of normal switching functions.

The batteries were built especially for our use by Charger Battery Co. of Okanogan, Washington. Though not as heavy or powerful as the Trojan L16W, we did not have to pay the high shipping costs normally associated with batteries, and the entire set of 20 cost only $1270.00. They should last at least 10 years under the conditions that we use them. They are stored in a room inside the house that is dedicated to electrical gizmos. The temperature is maintained at 70° and daily checks are made on the system. A 5 gallon jug supplies distilled water to maintain the water level in the batteries. A problem of major concern was how to dispose of Hydrogen gas, formed during battery charging. The solution was to put a 3 inch PVC pipe through the outside wall, and each cell is vented to this pipe via plastic tubing, which is placed in a hole drilled in each cell cap. This system works very well.

We never use the batteries below 50% capacity, which after derating by 20%, gives 100 ampere-hours use before recharging is needed. Based on our daily use of 1108 watts, we can go for 10.8 days before 50% discharge is reached. Normally, with the winds that we get, the batteries are recharged, at least partially, each day. We occasionally shut off the generator for a week or so to allow the batteries to when our electrical load would be the greatest, so it was where the emphasis was placed. Since the BWC-1000 will produce power at 9 MPH, it looked like we had a good location for wind power. Over the last 2 years, we've had to start the Kohler on the average of twice a year, so the system is working efficiently.

Tower Construction

I will, very briefly, discuss the Rohn Tower that supports the wind machine. The tower is an important part of a properly functioning wind system. Bergey Windpower Co. includes an excellent installation manual with their wind machine. It contains plans on laying out guy cable anchors and tower foundation construction that are easy to follow. The tower goes up in 10 foot sections with a gin pole purchased just for that propose. The tower is normally guyed at every 27 feet,

cycle, which helps keep them active throughout their full range. Wind Study

One should never install a system without a study of the winds. We lived at this location for several years before starting the system, and had an opportunity to observe the wind patterns. The wind appeared to blow often enough to charge batteries, provided it was strong enough. We purchased a Model SWE 6010, wind anemometer from Sencenbaugh Wind Electric, and it worked very well. At the end of 1 year, we had the data that was needed to make a decision. The average wind speed from December thru April was 14.0 MPH. This time period was but when you have two people climbing on it, the structure sways to the point where it is uncomfortable. We used temporary guy ropes between the permanent cables to stabilize the tower. The 3 ground personnel pulled each section up with a rope and we bolted it in place, then moved the gin pole to the top of that section and started the process again. 60 feet does not sound very high when looking from the ground, but when you are hanging out of a small safety belt, your outlook changes. We put up the tower, including the wind machine, in one day and still had time to consume a few beers.

It is important to place the wind machine in undisturbed air if it is to work efficiently. It is recommended that it be placed at least 30 feet above any obstruction within 300 feet of the tower. There are a number of reports available, which have been written on wind power siting, one of which is found on page 16 of Home Power Magazine #1 written by Larry Elliott.

Photovoltaic System

The second part of our electrical system consists of a set of 6 each, 2 volt industrial cells of 1780 ampere-hours, which were purchased when a telephone company moved its location and replaced them with new cells. These type of batteries are worth looking for and can usually be purchased reasonably. New, they can cost up to $600.00 each, but we got our set of 6 for $645.00. As an example of their longevity, there is a set at Chief Joseph Dam in Bridgeport, Washington, that have been in place for 33 years, and are still in good condition.

Power Conversion

We are utilizing a Heart Interface inverter, Model HF 12-2000XW, which will handle surge loads up to 5000 watts. This surge capacity is necessary for the heavy starting loads such as automatic washing machines, submersible well pumps, and heavy power tools. Our experience with the Heart inverter is limited since we have just purchased it, but they came with high recommendations & we expect it to function flawlessly.

12 Volt DC Power

12 volt power is being used directly from the batteries for our entertainment center and will soon be used on a Sunfrost F-10 freezer. Presently, we are using 597 watts of 12 volt DC power on electronic equipment which includes a 10 inch Emerson color TV, a Radio Shack Citizen band radio and a Realistic AM-FM radio and cassette player. The only other load at this time is the inverter idle current.

The primary method of charging the 12 volt system is 4 ARCO M-75, 47 watt photovoltaic panels. Future plans call for the addition of 8 panels, installed on a Zomeworks Track Rack.

120 Volt ac Power

The third part of our electrical system is 120 volts AC. The primary power source is a Honda ES-6500, a 6500 watt generator. It presently powers a submersible well pump, automatic washing machine, air compressor, various power tools and small appliances. The ES-6500 automatically slows to an idle when the load is removed, and is very miserly on fuel. It uses 15 gallons of gas per month at a cost of $14.70. Oil and filter changes are accomplished about every 3 months, with costs running about $2.50 per month. This brings the total monthly costs to $17.20 for 20 hours of use, or $0.86 per hour. After the inverter system is fully functional, the ES-6500 will be used only for backup power and heavy loads such as table saws, air compressor, skill saw and heavy power tools. The system is set up so we can quickly switch the ES-6500 in or out of the electrical system. The Heart inverter is similarly isolated by a fused switch.

Explanation Of The System

The rationale behind using 3 voltages was to achieve the best of each system. The reason that we used 120 volt DC, was the ability to use standard code electrical wiring, the capability to use universal appliances and standard 120 volt AC light bulbs. The bulbs do not care whether it is AC or DC power. The system doesn't have the disadvantages of inverter losses

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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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