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Monday, June 2, 2003
Wind turbines generate interest
By DERCUM OVER /
Correspondent
OAK HILLS — Rural homeowner Gus Sansome stood in his yard on a windy day in
April, examining a sleek-looking yellow machine that weighs about 500 pounds.
Photo by Dercum Over
Gus Sansome gets ready for summer in the shadow of his 10-kilowatt wind turbine,
perched atop an 80-foot tower. Sansome added 20 feet to his tower in April,
increasing its power output by 36 percent.
It's about the size of a riding mower — except the
blades are 10 feet long.
Sansome, a retired health administrator, decided to buy his 10-kilowatt wind
turbine generator in August 2001, after watching one that belonged to a neighbor
churn out free power month after month.
"I haven't paid an electric bill since," he said.
The machine was sitting nearby on the ground in his back yard so a team of men
could add 20 feet of height to his 60-foot generator tower.
His decision to invest more money by adding height to his tower is a testimony
to Sansome's faith in the technology.
After a year collecting daily output data from the generator at 60 feet, he
decided to elevate the machine, and therefore the amount of electricity it
generates.
He plans to cool the house with it in the summer and heat it this winter.
There are three moving parts:
• A permanent-magnet generator is attached directly to the blades and whirls
when they do, driving the current down a conduit wire to a power inverter on the
ground.
• The main body of the generator swivels to face into the wind.
• The tail of the machine serves double duty as a counterweight that
provides the brakes on the machine.
When the wind blows too strongly, the weighted tail lifts up and initiates the
"furling" mechanism which swings the blades away from the wind,
thereby protecting the device from damage under severe conditions.
The simple design means low maintenance, too. The company recommends lubrication
once every seven years.
One barrier to the wind turbines' proliferation has been a county ordinance
mandating a maximum height of 35 feet to any structure.
The latest county ordinance — enacted last year — now permits a tower height
of 100 feet on a 21/2-acre lot, and 120 feet on 5 acres.
Height alone is not the main reason there's not a windmill out behind every
garage already. It's also the cost of the things, of course.
The $40,000 ballpark price for the Bergey Windpower Co.'s 10-kilowatt generator,
including a power inverter and installation, is a big enough bite to discourage
anyone, especially those who may not know how long they plan to live in the same
place. [ Note: Mr. Sansome received a rebate of ~ $20,000 from the California
Energy Commission. ]
Sansome has figured that his windmill will pay for itself in six to eight years.
The life of the gadget is estimated to be 25 to 30 years, which equals a lot of
free energy over a long period of time.
Southern California Edison representative Laura Rudison estimated more
conservatively the span of time before the average homeowner would break even.
"When you really run the numbers, it may be 12 or 15 years," she said.
[ if you ignore the CEC rebate ]
Rudison is the project manager for Edison's Net Metering Program, which does
business with customers who generate their own electricity.
Because neither the wind nor the sun provide continuous sources of power, most
of those who generate power from them also rely on Edison to provide power at
night or on a calm day.
By using an electric meter that runs both backward and forward, the Net Metering
Program allows small, private generators to barter the power they use for the
power they generate on a one-to-one basis.
So, at the end of a year, Gus Sansome has generated enough power during the
windy months of the fall and spring to make up for power that he drew from
Edison's grid during the calmer months in the summer and winter.
A lot of rural High Desert real estate has this "river of money"
blowing overhead. U.S. Department of Energy wind maps show that the peak, or
class six, wind resources available in Tehachapi and near Palm Springs are
strong enough for huge generators that provide power to the regional grid. But
they also show that residents near the top of Cajon Pass enjoy an advantageous
class-five wind resource. Over much of the Mojave Desert, even class two and
three properties are a pretty sure bet for benefiting from the size of generator
needed by a homeowner or small businessman.
Bergey's 10-kilowatt machine was designed to pay for itself in a class-two wind
resource, said Tod Hanley, chief engineer at Bergey. A class-two wind source has
an average wind speed of 12 mph, measured over a yearlong period.
The 10-kilowatt Bergey turbine begins to turn and generate in an 8 mph breeze.
For those curious about the wind resource flowing over their property, local
weather histories are available at some weather monitoring stations, and small
anemometers are available for purchase by those with a penchant for
experimentation.
(Reprint by permission of the Daily Press,
all rights reserved)
[ This system was installed by
Guasti Construction, Oak Hills, CA. Tel: 760-949-0480, E-mail: GuasiConst@aol.com
]
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