Nobles project a
201 MW addition to wind power numbers
Amidst all the talk and
Washington about what constitutes "clean energy", major U.S. utilities
are quietly increasing the nation’s wind generating capacity.
Xcel Energy recently added to the nation’s wind generating
numbers with its 201 MW Nobles wind farm in Minnesota.
In his State of the Union address earlier this year, U.S. President
Barack Obama clearly put the challenge out there for the alternative
energy industry: he outlined the goal of achieving 80 percent of U.S.
electricity from "clean energy sources" by the year 2035.
201 megawatts, Nobles Wind is Minnesota’s second largest wind
power project. The project involved M.A. Mortenson Construction
erecting 134 GE 1.5-megawatt wind turbines on 42 square miles of
farmland in Nobles County, about three hours southwest of Minneapolis.
The American Wind Energy Association’s Denise Bode was quick
to respond, noting the industry stands ready to move
ahead—now—in a significant way. "Wind energy is
ready to go now; we don’t need to wait nearly three decades,"
she said. Bode noted that by 2030, wind can be up to 20 percent of the
electric supply all by itself, according to a study done by the Bush
Amidst all the talk and politics, though, America’s utilities
are carrying on with business, and are continuing to add to the
nation’s wind generating capacity. The U.S. wind industry
built 5,115 megawatts of wind power in 2010.
One of the larger projects, completed toward the end of the year, was
the $500 million Nobles wind farm in Minnesota, developed by enXco and
built by M.A. Mortenson Construction, for Xcel Energy. At 201
megawatts, it is Minnesota’s second largest wind power
project. The largest is the 205.5 Fenton wind power Project that enXco
owns, which is in the same area of southwest Minnesota as the Nobles
project. Fenton supplies power to Xcel Energy.
The Nobles wind project moves Xcel Energy further along toward its
target of generating 30 percent of its retail electricity from
renewable energy sources by 2020. Most of the electricity generated by
the project will be used by customers in the Twin Cities metro area.The
project involved Mortenson erecting 134 GE 1.5-megawatt wind turbines
on 42 square miles of farmland in Nobles County, about three hours
southwest of Minneapolis. Mortenson also installed 36 miles of access
roads, 86 miles of collection system, 134 foundations, a switchyard to
feed an existing substation, and an Operations and Maintenance
The Nobles wind project is the 17th wind power facility that Mortenson
has built with long-term partner enXco and is the second project that
enXco and Mortenson have constructed for Xcel Energy. The Nobles Wind
Power facility became operational this past December.
Rick Halet, the project manager for Xcel Energy, explained that the
Nobles wind farm project followed pretty much a straight chronological
timeline. "Contracts for the project were signed in late-2008, the site
development work happened in 2009, and wind farm construction took
place in 2010," he says.
"We went through a Request for Proposals process, and the Nobles
project was one of the projects offered in the bid process."
The wind-rich site appealed to both the developer, enXco, and of
course, Xcel Energy. "This particular project happened to be at a site
where it would interconnect directly to the Northern States Power Co.
(NSP)-owned transmission system," he said. NSP is an operating company
of Xcel Energy. "That was a bit of a plus, but it was not an overriding
factor in its selection. The wind capacity for the site was in the high
30 percent range, almost 40 percent, also making it an attractive site."
The Nobles project and several other wind projects are located in the
wind "sweet spot" of Minnesota—Buffalo Ridge. "It is one of
the highest wind resource areas in the state, if not the highest," says
The Nobles project site starts west of the town of Worthington,
Minnesota, and goes north of I-90. Although it involved construction of
a fair bit of access road, the project had the benefit of the section
road system that exists in rural Minnesota, and many Upper Midwest
states. Basically, there are east/west and north/south roads every
mile. "Some of the roads are well established, some are paved, and,
well, some are just gravel," says Halet.
There were also some minimum maintenance roads—a very apt
description, he notes. That said, working with any type of road is
better than having no road to work with.
The project developer, enXco, had a fair number of landowners to deal
with—81 landowners, to be exact. The company met with
landowners individually and also scheduled public meetings, to keep the
community informed about the project. Xcel Energy representatives also
participated in the public meetings.
Xcel Energy has done a number of wind power projects, and Halet notes
that support for wind power projects in a community can vary. "They can
receive a lot of support in principally agricultural areas. The
landowners look at turbines as another kind of cash crop on their land,
a revenue source.
"In areas where you have landowners with hobby farms, or where people
move to the country and commute to jobs in the city, it can be a
different reaction—you run into less support in those
The area where the Nobles project was built is strongly agricultural,
so it received the support of local farmers.
In addition to the revenue wind projects bring to land owners, some
local governments are also paying more attention to the tax revenues
that wind projects bring to an area. The revenue is very welcome to a
county’s coffers. The Nobles’ turbines are located
within Olney, Dewald, Larkin, and Summit Lake townships.
As is usual with Xcel wind power projects, a number of environmental
studies were carried out for the Nobles project.
"There is a standard set of studies that forms part of the development
process," explained Halet. "This includes wetlands delineations and
threatened and endangered animal and plant
species—it’s an extensive environmental analysis.
"It also includes any aviation issues, to make sure that where we site
the turbines is not going to interfere with any kind of aviation
traffic, and also developing a lighting plan to determine which
turbines need aviation lights." There are also studies to locate
microwave communications beams that may go across the site, so there is
no disruption in communication signals.
"It’s a robust set of studies that also includes cultural
types of resources, with an archeological study done where roads are
being built and turbine sites to make sure there aren’t any
culturally sensitive areas."
Buffalo Ridge, where the project is located, is a broader ridge with
gradual inclines and declines, rather than a narrow, high ridge, as
might be seen in other areas of the U.S. The region is characterized by
rolling hills and, of course, high average wind speeds.
This part of Minnesota is actually part of the Mississippi
River/Missouri River divide, with water flows to the east eventually
flowing into the Mississippi and water flows to the west eventually
flowing into the Missouri.
The Buffalo Ridge region has some recent history with wind power. The
first wind turbines were reportedly built in the area in 1994 by the
Kenetech Corporation. In 2006, PPM Energy (now part of Iberdrola
Renewables) and Xcel Energy built the 150 MW MinnDakota wind power
project that straddles the state boundary between Brookings County,
South Dakota, and Lincoln County, Minnesota.
Construction-wise, Halet says the Nobles project was fairly typical, in
that there were some weather challenges, but nothing unmanageable. "The
summer was a bit wetter than normal, and that caused a bit of
difficulty," said Halet, who spent the summer on the site, along with
eight other Xcel Energy people, overseeing the project. "The rain meant
waiting for some of the roads to dry out so we could move some of the
more heavy loads."
There were the usual regional weather issues to deal with such as
thunderstorms. This kind of weather has a big impact on a wind power
project—unlike other energy-related construction projects,
say a natural gas or coal power plant—because the work on
wind power projects is all outside, notes Halet. "If there is a
thunderstorm or lighting in the area, you call everybody in.
"Safety is the number one thing—no job is so important that
you want to put people in harm’s way, no matter whether you
are on schedule or behind schedule."
Depending on the phase of the project, weather is also more of a factor.
"When lifting and stacking large turbine components, you generally
can’t do that in winds over 22 mph. If the wind is high on a
particular day, you have to shut that activity down. Once the turbines
are up, there is internal wiring to do, but you don’t want
people in towers doing that work when you’ve got lightning in
The southern boundary of the project
site is up against I-90, just west
of the town of Worthington, which was helpful
in terms of bringing in
equipment and components.
The daily work flow was fairly predictable, with each morning starting
out with Plan of the Day meetings, so everyone on site was in the know
on what was happening that day on site.
Big picture, wind projects are all about work flow, says Halet. "You
start with the civil folks putting in roads, followed by the foundation
and all the concrete work, and then you have the turbine parts
delivered and erected." But he noted, as with all wind power projects,
the work is not quite as separate as it sounds.
"With this whole process, there are some points towards the middle of
the project where you actually have the major activities all going on
at once. You still have people building some road, you have people
building foundations, you have people erecting turbine components, and
you have electrical contractors trenching cable."
That represents a fair number of activities—and
people—for the contractor, Mortenson, to orchestrate. The
work force on site peaked at about 300 people.
In some ways, a wind power project is like a train that has to keep
moving forward—it can’t be waiting at the station,
or at least not for very long. "You don’t want any people
waiting because of something not being ready," Halet explained.
"You don’t want the foundation people waiting
because the roads aren’t ready, and you don’t want
the cranes, which are expensive, waiting for turbine component
deliveries or waiting for the concrete in the foundations to come to
their full strength so they can start erecting equipment."
In many respects, the construction and management skills required for
building a wind farm are similar to the skills required for any major
energy project, notes Halet.
"To the extent there are differences, it’s probably more in
the development phase," he says. "With a project like Nobles, the
developer is dealing with 81 landowners and the issues of having a 42
square mile site versus something that is more compact, a coal or
natural gas powered facility, for example."