Fed up with the noise, fumes, and cost of their gas-powered generator, a California family in California's Tehachapi mountains achieved energy self-sufficiency with a wind and solar power system.
After two years of powering our remote home on a small generator, my husband John and I were desperate. We had to eliminate the noise, gasoline, oil changes, and fumes or finally admit that what was originally envisioned as a conscientious attempt at energy self-sufficiency was turning into a terrific nuisance. One morning after we stepped outside to get a soul full of fresh air and instead caught yet another mouthful of exhaust, we contacted a couple of wind turbine manufacturers for specifications and wind data. Their charts and graphs, spread out over the kitchen table, provided information about equipment operation and wind velocity. Financial resources dictated that we move slowly, but we were determined to get moving.
One year later, John and I enjoy a rural lifestyle in the Tehachapi mountains with modern conveniences ...and no fumes. We convert both wind and solar power to 110-V household current. We also have a backup generator — just in case Mother Nature takes a rest. Our primary electrical supply is generated by a 1.5-kW Bergey wind turbine, mounted on a 50-foot, old-fashioned, stock tank windmill. The turbine is a 24-hour renewable source and the solar panels complement the power system on sunny days. During winter, solar benefts are limited by shorter days, but the wind is present across our mountains.
Our refrigerator, heaters, and water heater run on propane gas. On household current (stored in batteries and transformed from 24-V DC power to 110-V AC for the house outlets through an inverter), we operate a color TV, VCR, computer, printer, washer, dryer, 1,500-W hair dryer, water well and water pressure pump, garage door opener, water filtration system, and outdoor lighting.
But how did we get there?
Our first consideration was the tower. Typically, turbine manufacturers design their mounting plates to conform to the tower top. For example, Bergey uses the Rohn guyed-lattice tower, whereas World Power uses a guyed-pole tower. What this means is that you are something of a captive audience, having to buy a turbine specifically made for certain towers. And they don't come cheap.
The giant steel frame must be a minimum of 50 feet tall to reach stable air and preferably taller to ensure unobstructed airflow. It's hoisted to an upright position and stabilized with numerous guy wires; the turbine is then lifted on top by a crane (only experienced folk dare use a gin pole). The rotor and tail are installed in place and final electrical connections are made. Now, all that's required is a 7.5-mph start-up wind.
Maintenance schedules vary according to turbine design. Some towers are designed to be lowered to the ground for turbine maintenance rather than making you climb to the top. Contrary to some manufacturers' contentions though, lowering a 50–100-foot tower for any reason is no small job. The guy wires must be released and there must be adequate ground clearance and equipment with which to lower it. Maintenance is best left to the qualified and brave who are equipped with safety gear.
Now, that's how it should be done. Then there's the way we did it. We bought a 75-year-old, 4-legged, angle-iron windmill tower with lots of western character and no guy wires. We constructed two pivoting legs to tilt the tower—each in 1,500 pounds of concrete. The other two legs locked into place.
We ordered a World Power Whisper 1-kW turbine and modified the tower top with a 2-inch pipe according to specifications. We assembled, wired, and mounted the Whisper before we raised the tower. Neighbors came to lend a hand and we pushed it up with our tractor. We flipped it on with ceremonious gesture — and at last it was up and working! Well, Murphy (and his Law) apparently had taken residence at our place. The blades were out of balance and the generator was shimmying...a lot.
We ordered a new set of blades and installed them without lowering the tower. Now it spun smoothly and we had more electricity than we could use — until 3 months later, when we spotted the tail lying on the ground and noticed that the nose cone was cracked. We learned that World Power previously had problems with the tail and nose cone design. They offered to replace the turbine, but we felt the Whisper just wasn't up to the challenge. We lowered the tower, removed the turbine, and shipped it back. World Power refunded our money. Based upon this experience, we always recommend that anyone who is considering a wind turbine ask the manufacturer for references for people who have had that model turbine in service for a couple of years in a location with similar wind conditions.
Taking our own advice, we located Ed Wulf, a nearby resident who had a Bergey. He said it would "withstand our brand of wind." After much conversation, we ordered Bergey's BWC 1500, a 1.5-kW wind-power generator. It has three blades for better balance and turns out of the wind at 120 mph. This time around, we had the tower top configured by a technician who maintains 600-kW commercial turbines atop 160-foot towers. He also assembled and installed the turbine.
We built an outbuilding beside the tower to house the energy system. John designed it and had an electrician wire it to meet California's building code. Power generated by the turbine is processed through a controller and stored in a 24-V DC, deep-cycle battery array. From the batteries, a sine wave inverter supplies our 3,100-square-foot home and a 1,200-square-foot garage with 110-V AC electricity.
When the batteries are fully charged, power can be manually diverted to start the well pump to top off the 5,000-gallon water storage tank. If the inverter fails, a manual breaker switch automatically shifts to the generator. The system also operates a water filtration system.
The batteries are isolated in a well-vented, fire-walled room within the power center. Lead acid batteries are the weakest link of any alternative energy system; technology has simply not advanced to produce an affordable, long-lasting battery.
Our system is more than adequate, but this does not mean that it has no limitations. We are careful to turn lights off and wash only full loads of laundry. I sometimes iron clothes at midnight because that's when the excess power is available. But we have developed a sixth sense about our output capabilities. We even enjoy 27-W fluorescent lights (equivalent to a 100-W incandescent bulb), low-voltage garden lights, and motion detectors.
The cost for our hybrid system is about $10,000. Yes, it's a lot of money, but we didn't spend it all at once. We began with a 5-kW generator, inverter, and batteries. When we could afford it, we upgraded to a 10-kW generator. Then we bought the windmill and gradually added PV panels.
Statistics indicate that the operating cost of a 1,500-W wind system is $1.93 per watt. But the payoff for nonpolluting electricity cannot be equated in dollars. Its value is realized in terms of self-sufficiency and quality of life.