SOLAR POWER system
cuts university's carbon footprint—and power bill
William
Paterson University in New Jersey is cutting its
carbonfootprint—and its energy bills—with the
largest solar PV panel system installed at a U.S. university: a total
of 3 MW of panels on rooftops and on top of carports.
By
Vicky Boyd
SunDurance Energy LLC recently received an education in New Jersey
geology—working on a bustling university campus and designing
aesthetically pleasing carports—when it built a 3-megawatt
solar system for William Paterson University.
The
Edison, N.J.-based solar energy
developer passed the test by
working closely with university leaders and campus police at the
11,000-student campus in Wayne, N.J.
The
project, which will supply 15 to
20 percent of the campus' power
needs, is also the largest PV panel system at a U.S. university to date.
"It's
been so well received," says
Stephen Bolyai, university vice
president for administration and finance. "I've never had anyone say,
‘why did you put those ugly things in our parking lots?' The
campus is extremely complimentary on what we've done. These are a very
visible example of saving energy and cutting our own carbon footprint."
The
project is also a prime example of
how a public institution can
successfully pair with private companies, he says.
Nautilus
Solar Energy LLC of Summit,
N.J., financed, owns, and operates
the PV system under a 15-year power-purchase agreement with William
Paterson University.
In
return, the university will buy the
solar power at a reduced rate
that is expected to save it more than $4.3 million on its energy bills
over the life of the contract.
Energy
conservation and energy
efficiency have been at the forefront of
the university's activities for the past 10 years, Bolyai says. In
fact, the institution has cut its energy use by 30 percent even though
its physical plant has increased by 25 percent.
"Employees
and student clubs have been
very active," Bolyai says,
referring to energy conservation. "Like most universities, we're trying
to do more with less resources and without raising tuition. It's not
just solar panels. It's lighting retrofits, HVAC controls,
single-stream recycling, occupancy sensors, and any feasible energy
savings idea."
In
2007, the university was a charter
signatory to the American College
& University Presidents' Climate Commitment, a national
initiative with a goal of carbon neutrality at member institutions.
More
recently, the university received
a grant to install smart
controllers to monitor systems in its buildings. It also replaced all
of its boilers with more efficient gas boilers.
When
university leaders moved to the
next step of installing solar,
they not only looked at long-term cost savings but also how the project
would mesh with the university's philosophy.
"We
recognize the university's social
responsibility, and as citizens,
we all have a social responsibility to reduce our carbon footprint,"
Bolyai says. "It's doing the right thing."
The
university first began considering
a PV roof-mount project about
four years ago. But most of the roofs were too old or had too many
penetrations to make them cost-effective.
"They
had tried to bid the project a
bunch of times, and they really
wanted some innovative ideas and somebody who would get the job
finalized," says Chris Krempecke, SunDurance project leader.
SunDurance
proposed building carports
and installing the PV panels on
top of them. The resulting project involved three roof-top mounts,
accounting for about 30 percent of the total project. The remaining 70
percent were installed atop the carports.
|
|
|
PV
arrays were set on precast
foundations 30 inches in diameter, sunk 6 to 12 feet in the ground,
depending on the bedrock. The challenge was the bedrock differed under
each site.
|
As part of the winning bid, SunDurance had secured a Power Purchase
Agreement (PPA) contract with Nautilus, Krempecke says.
Bolyai says university leaders liked the idea of a PPA because the
institution had no up-front capital costs.
"Also we felt we didn't want to have to operate the facility," he says.
"If we owned it, we'd have to have people on site and maintain the
panels."
In winning the bid, SunDurance had to meet the university's strict
criteria.
The project couldn't reduce the number of overall parking spaces, since
the urban campus already has more parking demand than it can supply,
Bolyai says. The structures had to be aesthetically pleasing, they
couldn't infringe on future parking lots, and no trees could be removed
during construction.
In addition, the contractor would have to work around everyday student
comings and goings and cause minimal impact on campus operations.
PV arrays were set on precast foundations 30 inches in diameter sunk 6
to 12 feet in the ground, depending on the bedrock. The solar PV arrays
were fixed in place and tilted at a 10 degree angle toward the south.
What SunDurance soon found out was the bedrock differed under each site.
"When you drilled into rock, every single hole was different,"
Krempecke says. "You could spend hours drilling with the wrong piece,
and it took getting the first hole down. Then we'd know the type of bit
you had to use to fix the drill width."
SunDurance turned to the expertise of its sister company, Conti
Enterprises Inc. of South Plains, N.J., which specializes in
engineering and construction.
"A whole lot of different methods were used to find the right equipment
that worked the best," he says.
Because of the drilling challenges, some shifts were extended, second
shifts were added, and some Saturdays were worked to recover lost time
spent figuring out the bedrock. They also brought in a second drill
when the project began to fall behind schedule.
"We learned a lot about how to drill that part of New Jersey,"
Krempecke says.
HBC Electric Co. Inc. of Lodi, N.J., along with members of the
International Brotherhood of Electrical Workers Local 102, brought its
expertise to the site as the electrical contractor.
On top of the drilling challenges, the companies had to work around an
overcrowded campus and could only block off a couple of lanes of
traffic—one for deliveries and one for construction.
So Krempecke says they had to work in stages, bringing in only as much
material as they could use that day.
"It was just in time," he says. "It was a little bit of a headache."
They also worked closely with campus police to keep curious onlookers
at a safe distance or have cars towed that were parked illegally in the
construction site.
"They were a big help," Krempecke says of the police.
SunDurance always had a manager on site and met regularly with
university leaders to keep them abreast of the project.
Ground was broken in February 2010, right in the middle of the school
year. The project involved six connections completed in three different
phases. The first was to be finished by early June; the second, the end
of July; and the third by the end of August 2010.
The construction site did receive a bit of a reprieve during summer
school, when fewer students attend the campus.
|
|
Compared
to a traditional
ground-mounted system, the William Paterson carport project had to span
longer spaces with fewer columns to
accommodate cars and pedestrians
moving beneath it.
|
|
|
|
Compared to a traditional ground-mounted system, the William Paterson
carport project had to span longer spaces with fewer columns to
accommodate cars and pedestrians moving beneath it. Wind and snow loads
also had to be figured into the project's engineering, which was all
done in-house by SunDurance.
Because of safety concerns, William Paterson required the lighting be
the same as it was before the construction. Upon completion, the
lighting actually was better because of new highly efficient
structures.
The carports also were designed to complement the university's 370-acre
hilly campus. Lot 6, for example, is set on a hillside and comprises
six tiers, each 10 to 15 feet higher than the previous one. The tiers
also follow the curvature of the hillside.
"It was really challenging to design these facilities," Krempecke says.
ProTek Park Systems of Cincinnati, Ohio, manufactured the parking
structures.
On the rooftops, SunDurance used the PanelClaw installation system, a
three-point non-penetrating roof-top mount by PanelFlow, of North
Andover, Massachusetts.
Krempecke says they chose the PanelFlow system based on their past
experiences.
"They came out with a relatively new product at a time when we were
spending a lot of time researching it," he says. "In each of the
installations, it would rank in the top tier."
Altogether, the roof-mount and carport project involved 11,780 230-watt
polycrystalline Yingli Solar panels from Yingli Green Energy
of Baoding, China.
Past experiences with the product, as well as price, reliability, and
availability, played into its choice for use at William Paterson
University, Krempecke says.
Relationships also played into the use of PV Powered inverters from
Advanced Energy of Fort Collins, Colorado.
"We have preferred vendors for equipment—based on price and
warranty and the strength of the company," he says.
William Paterson University isn't stopping with 3 MW, Bolyai says.
University leaders are looking to add another 500 KW of roof-mount PV
on top of a few additional buildings as soon as rooftop improvements
are completed.
A new 1,000-space parking garage, which is in its infancy, will also
feature rooftop PV panels.
"We're just in the process of selecting an architect for the garage,"
Krempecke says. "We've even looked at having wind turbines on campus.
We haven't gotten too far into it because of concerns about 300-foot
towers. Alternatively, we're looking at smaller versions of those.
"We're also investigating replacing fixtures with LED [lighting]. It's
an ongoing activity. It's very embedded in what we're doing here."
July/August 2011
|
|