Small-scale windmills generate mixed reviews
Apr 5 - McClatchy-Tribune Regional News - Diana Bowley Bangor Daily
News, Maine
Greg and Norma Dyer have a message for homeowners looking to harness
wind power for a dependable source of electricity at low cost.
"Don't do it -- it doesn't pay off," Greg Dyer said recently. "Going
green is not what it's cracked up to be."
The only thing the $15,000 Skystream 3.7 wind generator they had erected
in June is good for, he said, is a Christmas tree. "I'm going to string
lights on it, but it won't even run the Christmas lights I'm putting on
it."
While the Dyers, who live on Route 7 in Dover-Foxcroft, are unhappy with
their purchase, others say their windmills have generated what they
expected, but they say location is the key.
Joseph Nesin of Chester, who installed a 10-kilowatt Excel
windmill atop a 140-foot tower on Pea Ridge Road, has produced more than
90 percent of the power he has needed for his approximately
2,000-square-foot veterinary office.
"It is doing exactly what we hoped it would do," Nesin said last month.
"It was installed with the hope that it would provide somewhere between
80 to 90 percent of the power that I needed and it's actually performing
higher than that." He said windmills have to be high enough in the air
to get the wind stream and to avoid ground obstructions such as trees
and buildings.
Mike Paradis of Green Earth Energy of Fort Kent, who sold and set up
Nesin's windmill, said he also sells Skystream windmills, but he has
found they are so new that they have some "initial issues." He said he
has had to do repairs on most of his Skystream units as opposed to other
units. Adequate tower heights are not supplied for the model, although
they are still a good wind turbine, Paradis said.
Greg Dyer said he thought he had the location and height covered. He was
told that his location was perfect for wind power. Rather than install
the wind generator the typical 50 feet, he went 20 feet higher, figuring
it would perform better in the somewhat wooded area surrounding his
home.
"It was installed in June and we've had it for 10 months and it has put
out an average of 5 kilowatts a day," Dyer said. In contrast, he said,
"We use between 20 and 30 kilowatts a day, depending upon what we are
running." Dyer said he was expecting the windmill would produce about
half the electricity he and his wife use.
Debra Burdin, co-owner of Burdin's Renewable Energy of Dexter, the
company that sold and installed Dyer's Skystream unit, said his windmill
is producing well considering it's the least expensive model he could
have bought from her. Burdin said the company has had no trouble with
other Skystreams that it has installed in the region. Although she said
the height of Dyer's pole is adequate, she suggested that the
surrounding trees on Dyer's property might be blocking some of the wind.
While wind may be the fastest-growing electric energy source, home
windmills aren't for everyone, according to Richard Hill, professor
emeritus of mechanical engineering at the University of Maine.
"If you have a great deal of money, and you hate the public utility and
if you think you live in a windy place, you'll be very disappointed when
you put up a windmill," Hill said recently. "You may, however, be
justified because you're interested in principle."
It was the principle that drew Dr. Steven Arnold of Range Road in Dover-Foxcroft
to install a Skystream wind generator on a 53-foot pole. "I didn't
really do it because I thought that it could replace buying electricity.
I did it because it's clean," Arnold said recently. "And although it was
quite expensive, I don't care one way or the other because I'm doing
something good."
Arnold did say, however, that his windmill hasn't delivered more than
100 kilowatt-hours a month, although it was advertised as capable of
generating 400 kilowatts-hours a month. "I can tell you it doesn't
generate anywhere near that," he said. Arnold has found that the wind
must blow at least 8 mph to get his windmill going.
"Initially, I wasn't really very happy with it, but the more I watch it
spin, the more I know I'm doing something," Arnold said. "I would have
liked it if it had made more, but I'm satisfied that it makes
something."
Duke Leighton of Jennings Hill Road in Dexter said windmills aren't for
everyone, but he's pleased with his purchase. His windmill, installed on
an 80-foot pole in September 2009 by Burdin's Renewable Energy,
generates about 20 to 30 kilowatt-hours a day. Leighton figures that
during the windy months, the windmill has taken care of 50 percent to 60
percent of his electric bill.
Leighton said his location is so windy that it bent his flagpole. He
said he spent about three years researching windmills before he took the
plunge. "Wind is a funky thing -- it's like a river in the air," he
said.
"It's a long-term project; it's not something that's going to be paid
off in a year or two and I knew that," Leighton said of his $15,000
investment.
Hill said a small difference in average wind velocity makes a "great
big" difference in how much a windmill can generate. How high a windmill
is from the ground makes a difference because "the boundary layer effect
on the ground slows down the wind," he said. There also are benefits
associated with a larger-diameter wind-mill that has air foils and
variable-pitch propellers, but that's essentially not realistic for a
single user to justify the cost, he noted.
While Hill does not disparage wind power, he said it disturbs him that
there are no supporting data for the larger wind turbines. No one has
published the kilowatt-hours a year that are generated from Mars Hill
and Kibby Mountain and compared those with the kilowatt-hours a year
used in Maine and in New England, he said.
Evelyn DeFrees, spokesman for the Maine Public Utilities Commission,
confirmed Monday that there are no figures available to the public about
the kilowatt-hours generated from Mars Hill and Kibby Mountain because
those operations are part of a competitive market. The PUC does not
regulate the generated market; rather, it regulates only the
transmission and distribution companies that move the power around,
according to DeFrees.
Hill said a household on average uses about 100 watts per square meter,
which includes electricity, heating and air conditioners.
"A wind farm, if you space the wind turbines out over the surface of the
land, don't do any better than 3 watts per square meter," Hill said. If
you make the windmills bigger, then they have to be spaced farther apart
or they will interfere with one another. So the 3 watts per square meter
are how much energy one can get out of a wind farm regardless of how big
it is, he said. Offshore, a windmill might get up to 5 watts per square
meter, but it's a "tremendous" surface area that has to be used. In
addition, because the wind is so dilute, one would have to run a lot of
wires to pull the energy together, he said.
"Whether you're talking the wind, the sun, the tide or whatever, these
are all very dilute resources," Hill said. And for that very reason, he
does not favor small wind turbines for homeowners. "If somebody asks me
about the small scale, I say, 'Don't do it,'" he said.
The semiretired Dyers wished they had had that advice before they made
their purchase. They have received a $4,000 state rebate for their
windmill but aren't sure if they qualify for the 30 percent federal tax
credit or cash grant.
"As it is right now, it's going to take us 55 years to pay this back
before we get a nickel out it," Dyer said. During that time, the
generator probably will have to be replaced two or three times, he said.
"Even if we do, down the road, get the federal money, we're still going
to be 20 years before it pays off, which we won't live long enough to
see," Dyer said.
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