In their quest for energy self-sufficiency, the Maltises settled on a Bergey 1.5 kW wind turbine after experiencing durability problems with their World Power unit.
PHOTO: MOTHER EARTH NEWS STAFF
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,
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