California wind project builder takes on all kinds of
weather with phase one of Alta Wind
The build-out of the Alta Wind project
in California will take a number of years, but the Balfour Wind Energy
Constructors' joint venture recently completed the 150 MW first phase
of the project. Along the way to completion, they ran into snow, heavy
rains, forest fires—everything, it seems, except locusts.
When it comes to wind power projects in the U.S., there's big—and
then there's extraordinarily big.
Easily falling into the second
category is the Alta Wind Energy Center in California's Mojave Desert.
Alta Wind will be the country's largest wind power project—it's
expected the project will generate up to 1,500 megawatts of renewable
energy. That represents enough power to sustain the electricity needs
of 1.1 million people or the equivalent of 275,000 California homes.
The project is being built adjacent to existing older wind projects
between the towns of Mojave and Tehachapi, about 100 miles north of Los
The Alta Wind project is owned by
California Highwind Power, a subsidiary of Terra-Gen Power. With more
than 1,550 MWs of generating capacity across 26 renewable power
facilities, the company is one of the leading renewable energy
providers in the U.S. Terra-Gen is said to be the only American company
that provides electricity on a utility scale from three major renewable
energy sources: wind, solar, and geothermal power.
The build-out of Alta Wind will take a
number of years, but the Balfour Wind Energy Constructors' (BWEC) joint
venture recently completed Phase 1 of the project. Along the way to
completion, they ran into snow, heavy rains, forest
fires—everything, it seems, except locusts.
And it's up there, in terms of
elevation. The Alta Wind Energy Center site is located in the foothills
of the Tehachapi Mountains, with altitudes ranging from 3,000 to 6,000
Despite the challenging conditions,
high elevation site, and an aggressive schedule, the project was
delivered on schedule and on budget, to meet the requirements of
delivering power to utility Southern California Edison.
BWEC is a joint venture between
Texas-based Balfour Beatty Construction and Oklahoma-based Wind Energy
Constructors. Balfour Beatty Construction is one of the largest
commercial contractors in the U.S., and Wind Energy Constructors is one
of the most experienced wind farm construction companies in the country.
The Mojave Desert site is familiar
territory to Wind Energy Constructors. The company has been involved in
almost every single project in the Tehachapi/Mojave wind corridor.
In addition to weather and
geographical challenges, the project also had to deal with a great deal
of environmental permitting, which in itself had an impact.
Due to environmental issues, BWEC
received Notice to Proceed with Alta Wind 1 some eight months after the
company was awarded the contract to build the project.
"Permitting issues affected the
project right through to its mid-point," said Kirk Tracey, project
director. "For example, once we started construction, a near-extinct
plant, the Bakersfield Cactus, was discovered. The owner diligently
worked on dealing with that while we diligently worked with them on
moving around the construction work sequence to accommodate the
An indigenous plant, the Bakersfield
Cactus was not known to grow above 3,000 feet; however, it was found on
the site. For its part, BWEC had to document the locations and numbers
to obtain permits to remove and relocate the plants. This required
multiple permits for upwards of 300 cactus plants. An environmental
subcontractor is also responsible for ensuring that the cacti stay
alive for several years.
The Mojave Desert Tortoise is not
protected everywhere but is listed as a protected species in this area
of California because of its low numbers. BWEC was required to install
tortoise fencing in all work areas. A biologist specializing in the
tortoise had to survey each work area. If one of the tortoises was
found, the biologist was the only one who could move it. The project
team was required to look under vehicles before moving them to make
sure that there were no tortoises, and if a gate was left open to any
of the work areas, the biologist had to resurvey the area.
Depending on which part of the site
they were working on, there were different sets of zoning. At one
point, BEWC prepared a map showing that there were seven different
zoning date requirements. The zoning went from the oldest, with little
requirements, to the most recent zoning, which had close to 100 zoning
or environmental impact restrictions.
"It impacted what we did," says
Tracey. "But in order to meet the spirit of all the zoning regulations,
we basically took a blanket approach. We treated each zone as if it had
all the restrictions as the most recently zoned areas."
Navigating the roads during
construction of the Alta Wind project could be an adventure, with
grades up to 20 percent. BWEC employed special equipment, such as power
haulers and graders as assist vehicles, to get wind turbine components
to the high elevation sites.
There was a very conscious effort to go beyond the environmental
regulations, which resulted in BEWC not receiving a single citation or
even a request for a remedy from any of the seven state and federal
government agencies involved.
Whenever a representative of an agency toured the site, a BEWC employee
would show them the detail and vigor they applied to meeting the
regulations. "It's typical of all of our jobs," says Tracey. "We
embrace the government agencies and kind of make them part of our team,
The site has five different landowners: CalPortland, Oak Creek Energy
System, GE, Terra-Gen Power, and the Bureau of Land Management. Oak
Creek is an existing wind farm with active turbines and existing
utilities. Close coordination was required with the property owners,
especially Oak Creek, to identify and relocate the utilities. This
required obtaining permits with the gas companies, county road
department, telephone, and gas pipelines and also permitting for
overhead utilities. The Pacific Crest Trail, a hiking trail from Mexico
to Canada, is a public-use trail that crossed the site. A portion of
the trail was relocated to preserve accessibility.
Since permitting was at different stages for different parts of Alta
Wind 1, it was a bit of a juggling act to keep the project moving
forward and keep construction equipment and crews busy. "There was
definitely a lot of re-sequencing involved, depending on which permits
were available," said Mark Bradley, director of preconstruction for
BWEC. "We built a wind project in New Mexico, where we got on top of a
mesa and built a long string of wind turbines. This was definitely not
one long string. We divided the project up into different
zones—Top West, North, Reflector Hill, Oak Ridge. The smallest of
those zones had three turbines and the largest had 20 turbines.
"So when a zone was found to have Bakersfield Cactus or there was
another environmental matter to deal with, that zone would be put off
to the side, and we would move work to the zones that were permitted.
It was not the most efficient method—we had to move equipment in
and out of some areas several times. But it was a team effort with the
project owners, Terra-Gen," said Bradley.
Helping out was the fact that turbine supplier GE had already delivered
the 100 1.5 MW turbines, and they were stored off site, allowing BEWC
to control the delivery of the turbines to the site itself.
Planning and communication are keys to any successful wind power
project—but even more so with Alta Wind, says Tracey. "We needed
that with shifting equipment and people around—especially when
you are in locations with very small crane pads, such as what we had.
The road would come in and run to a very small pad. You couldn't
pre-stage your tower components, so you are really doing just-in-time
All the towers were delivered by rear steerable equipment. Once a
delivery was made, the equipment could just be driven back off the hill
without turning around.
Just navigating the roads could be an adventure, with grades up to 20
percent. They employed special equipment, such as power haulers and
graders as assist vehicles, to get turbine components to the sites.
There was some access road built in the 1980s when Oak Creek was
developed with less powerful wind turbines. But it could not
accommodate the larger, modern turbines. "So we had to improve all
those roads," said Tracey. "And to get up the major grades, well, that
involved all new road construction."
They used a GPS mapping system, which generated 3D drawings. AutoCAD
Civil 3D software was utilized for civil engineering. BWEC used this
software for surveying, surface and grading analysis, earthwork
calculations, criteria-based geometric design, and automated machine
guidance. The mapping and drawing data were loaded directly on to the
The turbines are connected to Southern California Edison via six miles
of 230kv transmission line.
BEWC and its joint venture partners are accustomed to wild weather when
building wind power projects, but Alta Wind had its share of big time
weather. The fact that they had snow was not too much of a surprise,
considering the high elevation. Elevation varied on the site itself,
from 4,000 feet to above 6,500 feet. They had a month of high wind that
impacted crane and erection work.
"The biggest thing we had, though, was a 100-year storm," says Tracey.
"In one week, we received 10 inches of rain—that exceeded the
amount of rainfall that area gets in an entire year."
The ground could not accommodate that amount of rainfall, so they had
to immediately start a remediation effort, with seeding.
"We also had 25 days with temperatures over 100 degrees and a late
season snow/sleet storm with 50 mph winds," added Bradley. "The only
thing we didn't seem to get was locusts."
One benefit of building in the Tehachapi area is that major centers are
close, and there is a legacy wind industry support infrastructure. "The
Tehachapi has been built around the wind industry in the past, so it is
geared up to support that industry. Tehachapi, which is a good-sized
town, is close and Bakersfield was only slightly farther. We had major
freeways going in there." After the Alta Wind project, BEWC started
work on a wind farm in rural Kansas, and the logistics of getting
material there is significantly greater.
While BEWC has worked on a large number of wind projects, Alta Wind
once again confirmed the benefits of the joint venture company.
"What Wind Energy Constructors brings is a wealth of knowledge of not
only the technical aspects of wind turbines, but also the clients, the
trades side, and the people who have the expertise," says Bradley.
"What Balfour Beatty Construction brings to the table is the financial
strength for bonding, their risk management programs, and the ability
to manage large, complex projects. You put the two entities together,
and what we've seen is that we're clearly stronger as a joint venture
and are able to compete against the other major players whereas
individually, we probably could not compete."
It enables them to tackle tough projects, such as Alta Wind. "We had a
lot to deal with on that part of the project, the hills, the grades,
and the difficult constructability issues. The rest of the Alta Wind
project is down on the desert floor. It's flat, you have nice soil to
work with, you do not have the issues that we had to deal with.
"But then we look at ourselves as a company that comes in and handles
the difficult projects—we're not a cookie cutter project
company," added Tracey.
They take pride in being flexible and being able to change gears as
required—having not only Plan B in their back pocket, but plans
C, D, E and further through the alphabet.
"We put together a plan and that's great when it works—but we
have the flexibility to do the alternatives. The Alta Wind project
showed our ability to take a well-honed plan, make changes on the fly,
keep it moving, and make the owner's completion date," says Tracey.
As the EPC contractor on Alta Wind 1, BWEC worked hard to communicate
with landowners and other interested parties on the timing and progress
of the project.
"Terra-Gen had already engaged the community in communications," said
Tracey. "They got people on board to get the permit, and they had
community support in the nearby community of West Ranch—but I
think the support of the West Ranch Community was reinforced with the
The area was hit with a major forest fire in July 2010. Most local
residents were evacuated early on in the fire. BWEC employees assisted
the firefighters, providing fuel for the fire trucks, and filling the
water pools that the helicopters were pulling water from for water
drops on houses.
After the fire, local newspapers ran stories of area residents going up
to the trades people on the project, to personally thank them for
saving their house or a friend's house.
"They saw how the wind project owners and the contractors involved with
the project were there not just to develop and build the
project—but also to be good neighbors," said Bradley.
Forest fires are not usually one of the challenges you run into in wind
farm construction, Tracey added. "I have not been involved in a project
with this many challenges in a while," he said. "Usually you will have
one difficult aspect to a project—terrain, isolation, or weather.
But the challenges on this job just kept coming. But that was OK, these
are the ones you remember. You don't remember the easy jobs—you
remember the hard jobs."