Altamont Power Turns on New Wind Technology
May 06 - Oakland Tribune
Using technology imported from Denmark, a new wind farm in the Altamont Pass could generate more electricity at a lower price than its predecessors — while killing fewer birds of prey.
Obstacles to repowering — replacing wind turbines installed in the 1980s
with larger, more modern machines — include concerns about bird kills. To
claim lucrative federal tax credits, companies seeking to modernize their wind
farms also must negotiate new agreements to sell their power to Pacific Gas
& Electric Co.
The first wind farm operator to move forward with a repowering project in the
Altamont Pass is Altamont Power LLC, a partnership between Florida-based FPL
Energy and Global Renewable Energy Partners. GREP is a subsidiary of wind
turbine manufacturer Vestas Wind Systems of Denmark.
The new Vestas V47 turbines — brought on line in December by Altamont Power
at the companys Diablo Winds facility — use the latest materials, design
innovations and computer automation to squeeze more electricity out of the wind.
Company officials say fewer than three dozen new wind turbines at the Diablo
Winds facility on Altamont Pass Road have the potential to produce more
electricity than the 169 old FloWind turbines they replaced.
Although the new wind turbines are bigger than the vertical-axis egg beater
FloWinds, theyre also more sophisticated.
The fiberglass blades of the 31 Vestas turbines sweep through the air up to
258 feet off the ground, supported by steel towers weighing nearly 45 tons. Wind
gauges on each machine measure the direction and speed of the wind, adjusting
the angle of 77-foot- long blades to match conditions.
Like a bicyclist changing gears to climb a steep hill, adjusting the pitch of
the blades helps the Vestas turbines generate electricity at a wide range of
wind speeds — from 6 to 56 mph. Many older wind turbines only produce
electricity when wind speeds top 12 to 14 mph.
On a media tour of the Diablo Winds facility Wednesday, the blades of the new
Vestas machines whooshed audibly through the air, their generators cranking out
electricity in winds that hovered around 12 mph.
Acting on a signal transmitted from an office in Livermore, the blades of one
of the wind turbines were brought to a standstill so reporters could step inside
its 164-foot-tall tower.
These can be controlled from Livermore, or Florida, or from anywhere in the
world an Internet connection is available, said Steve Stengel, a spokesman for
FPL Energy. The company monitors wind turbines around the country from a
facility in Florida, allowing it to spot problems and troubleshoot from afar, he
said.
Pete Mallonee, an FPL Energy employee whos worked on wind turbines in the
Altamont Pass for 15 years, said the new turbines can record and transmit
details about their inner workings, simplifying their maintenance.
Once the wind turbines are broken in they only need routine maintenance, such
as lubrication of their bearings, every six months.
Keeping costs down is important because, like any other company, wind farm
operators are out to make a profit.
Stengel said Altamont Power has invested about $25 million in the Diablo
Winds project. The wind farm has an estimated 20-year life span.
To be eligible for a federal tax credit of 1.8 cents for every kilowatt hour
of electricity produced, Altamont Power was required to renegotiate its contract
to sell power to PG&E.
PG&E, which had been paying 6.8 cents per kilowatt hour under a contract
that was set to expire in 2016, negotiated a reduced rate of 4.3 cents per
kilowatt hour for the Diablo Wind project. That rate will be allowed to rise
with inflation to a maximum of 5 cents per kilowatt hour in 2016.
With annual electricity production of up to 65 million kilowatt hours —
enough to supply about 10,000 homes — the Diablo Winds project could generate
$21 million in revenue for the company during the 111/2 year life of the
contract. Thats about $11.4 million less than what Altamont Power would have
earned under its old agreement with PG&E.
The company wont actually lose money, though, because the FloWind turbines
that were scrapped had broken down long ago and couldnt be fixed.
Altamont Power and other wind farm operators may be less willing to negotiate
new contracts for older wind farms that are still generating electricity. Those
wind farms rely on other models of obsolete wind turbines, and parts to repair
them are more readily available.
FPL Energy operates wind farms with 220 megawatts of generating capacity —
nearly half of the total in the Altamont Pass — but hasnt submitted plans to
modernize other facilities. (One megawatt of generating capacity is enough to
supply about 1,000 homes, but most wind farms produce no more than one-third of
their rated capacity.)
PG&E is looking for ways to meet state mandates to obtain 20 percent of
its electricity from renewable sources such as solar and wind energy by 2010.
But the total generating capacity of wind farms in the Altamont Pass has been
capped at 583 megawatts until wind farm operators can prove they can reduce bird
deaths.
A recent study estimated that 881 to 1,300 birds of prey are killed each year
in the blades of wind turbines in the Altamont and on the power lines that carry
the electricity they generate.
State and federal wildlife officials, environmental groups, and the
California Energy Commission hope repowering projects will curb bird deaths by
reducing the total number of wind turbines in the Altamont by a factor of seven
or more.
In the future, power lines will be placed underground — the Diablo Winds
project eliminated eight miles of overhead power lines — and new turbines will
be sighted in ways to make them less lethal to birds.
Although the Diablo Winds project was allowed to proceed under the auspices
of a 1998 Environmental Impact Study, some other repowering projects will
require separate studies that can take a year more.
Buena Vista LLC is working with officials in Contra Costa County on an
environmental study of a proposal to repower a 37.5 megawatt wind farm on Vasco
Road. The company already has begun scrapping 179 old wind turbines, which it
proposes replacing with 38 modern machines.
Additional obstacles to repowering include the need to renegotiate leases
with ranchers who own the land the wind farms use, and potential disputes
between wind farm operators. Rows of larger wind turbines can create wakes that
have the potential to reduce power generation at turbines downwind.