Page 14 - North American Clean Energy September October 2015

solar energy

Solar Carports - Flexibility in design

by Michael Gumm

IN THE UNITED STATES, over 20% of the urban land area is dedicated to parking lots. Land and faster construction time. Solar carports constructed with lighter lexible thin-ilm
in urban areas is becoming an increasingly expensive and a scarce resource. Private and PV modules can use light-gauge roll-formed steel, which allows the support columns to
municipal owners of parking lots are searching for better opportunities to make their be placed further apart, creating a more open design.
parking facilities multi-functional and more productive.
Constructing solar carports using resin-based coatings painted on architectural

he installation of solar (photovoltaic or PV) carports on both private and public-owned standing-seam panels, and square rib corrugated metal panels with painted light gauge
parking lots provides a new and cost-efective opportunity for generating clean, renewable steel, provide a low maintenance, longer-service-life structure that blends in with the
energy without consuming additional land resources. Solar PV carports can provide far facility building design.
more power generation area compared to the more limited rooftop surface commonly used he lexible lightweight thin-ilm modules can be laminated onto architectural

for many solar installations.
metal panels at the factory and then shipped to the project site ready for placement
Parking lots in general have more solar potential and less shading issues than rooftop on the support structure, allowing the contractor to use pre-engineered modular
solar and can be easier to install than rooftop solar installations and be less disruptive to unit construction. his reduces onsite construction time, and subsequently reduces
the facility. Two additional advantages to mounting solar on carports versus roof-mounted construction costs.

solar arrays include no roof penetrations, which increase exposure to potential water leaks, Good wind and seismic performance engineering is important to carport design.
and the ability to avoid additional roof inspection or engineering and repair costs regarding With traditional glass modules, there is concern about the stresses of wind and seismic
the age, service life, and integrity of the building’s roof.
movement. In addition, purlins can sag when support columns are placed far apart,

Rooftop solar installation can have a huge impact on roof warranties and might shift impacting glass module and rail attachment. Architectural metal panels provide stifer
future liabilities from roof problems from the roof manufacturer to the building owner. support surfaces, can span wider distances, and are engineered for good wind and
Eventually, a rooftop array may have to be removed for a roof replacement and then seismic performance while using lighter structural support.
reinstalled, increasing the overall PV costs. hese risks and costs are eliminated with solar

carports.
Installing solar modules onto existing carports
Solar PV parking canopies ofer the parking lot owner and the environment considerable Many facility owners have existing carports without solar. Owners often want to retroit
value:
these existing carports, only to realize that the original design and construction will not
• Highly desirable shade for parked cars support the additional weight of conventional crystalline modules. Until now, the only

• Rain and snow protection
option was to tear down the existing carport structure, and to design and rebuild the
• Protection from hail damage
carport to support conventional solar.
• Reduced UV exposure
Flexible, lightweight thin-ilm solar modules can be installed over existing carports
• Reduced parking lot temperatures and heat island efect
constructed with architectural metal panels and some square rib corrugated metal

• Low-cost renewable power generation
panels without afecting the current weight limitation design. On carports with non-
• Low power distribution and energy transmission cost for the utilities compatible metal panel proiles, these metal panels can be removed and replaced with
• Improved municipal energy independences
new architectural metal panels without having to modify the existing support structure
at a cost lower than full replacement. Flexible thin-ilm modules can be installed onsite,

Lightweight, lexible solar vs. glass
requiring fewer installers and equipment, speeding up both new construction and
Traditionally, most solar carports use conventional, heavy-glass crystalline solar modules retroit installations, all at a lower cost.
installed on rails over large, heavy-gauge structural steel building components requiring When considering solar carports, new lightweight lexible thin-ilm solar modules can
large support columns with deep concrete piers or large ballast blocks. Even carports be considered the best choice to speed up construction at a lower cost, with more design

designed and built using architectural metal panels require additional heavy gauge lexibility than using conventional crystalline modules.
structural steel, railing, and roof clamps, all adding weight and cost to the solar carport.
Newer lexible lightweight CIGS based solar thin-ilm modules ofer the same high Michael Gumm is the founder of SolarPower Restoration Systems, Inc.
eiciency power output as standard crystalline modules, while weighting less than 0.7 lb/

sf vs the 3-5 lbs/sf for crystalline modules. he lighter weight of lexible thin-ilm solar SolarPower Restoration Systems, Inc.
modules means less structural steel is required in the carport design, which means less cost
www.solarpower-restoration.com | www.corporateroof.com

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