Page 26 - North American Clean Energy September October 2015

solar energy

Use of Aluminum in Solar Mounting Systems

Spreading Throughout the Country

by Jason Weber

Solar installations are surging throughout much of the United States as projects
move eastward from the strong California market. Light-weight aluminum

is proving increasingly popular for use in solar mounting systems for these
installations. he material’s advantages over steel have become more pronounced

as aluminum prices have declined to traditional levels since early 2015 when
premiums were at all-time highs.

According to GTM Research’s 2015 Solar Market Insight Report, a new solar project was systems, the weight reduction with extruded components can yield signiicant downsizing

installed every 2.5 minutes in 2014 as the industry grew 34%, and in the irst quarter
and cost reduction in drive systems and other components.
of 2015, residential solar installations surged 76% from a year ago. Relecting the move Building codes come into play which establish acceptable rooftop weight loads given the
eastward, nine states topped the 100-megawatt mark in solar power in 2014 and Solar winter conditions, especially in the Midwest and Northeast. his helps explain why alu-
Energy Industries Association (SEIA) anticipates that number to rise to 16 states in 2016.
minum is being used for mounting systems in a majority of the installed commercial roof

While sunny California continues to far outpace other states, last year’s top 10 states top and residential projects in those regions.
in installations included several in the Northeast and the South, namely, North Carolina, Additionally, the light weight helps small contractors because aluminum outperforms
which ranked second, Massachusetts, New Jersey, and New York.
steel in installation and shipping cost eiciency. For instance, Occupational Safety &
And while no igures exist on aluminum vs. galvanized steel and other rolled materials Health Administration (OSHA) regulations allow one person to handle 50 pounds, which is

for solar mounting systems, industry installers and other indicators point to aluminum’s heavier than most aluminum parts. By contrast, two people are needed to handle compara-
expanded use for both ground and rooftop mounting systems. Initially, galvanized steel ble steel pieces without factoring in the cost of lifting steel parts to a roof, where mechani-
was a favorite material, primarily because engineers were more familiar with the metal, and cal assistance may be required.
standard steel shapes were readily available.

he beneits of aluminum, particularly extruded aluminum, are becoming increasingly Strength and corrosion resistance is also key
apparent, regardless of where in the USA the mounting systems are located. It proves to be Aluminum is strong and corrosion-resistant, which means it requires less maintenance
easy to use and economical for a number of reasons.
than steel. Engineers can exploit the high strength-to-weight ratio that aluminum alloys

possess as well as aluminum’s corrosion resistance.
Aluminum’s light weight a major plus
he corrosion issue is an important one. In the San Francisco Bay area or along
Light weight is a critical advantage, especially in rooftop installations. his is especially true in Northeast coasts, steel parts must be recoated or otherwise protected to prevent rusting.
geographical areas where rooftop weights from heavy snow loads in the winter can raise concerns, As aluminum forms an instant and steadfast oxide ilm, protecting it against corrosion,

particularly on older rooftops. In the past, a rooftop solar energy project might not get built if the there is often no need to provide any additional coating for aluminum extrusions.
roof had limited structural capacity and the steel mounting system was heavy. But aluminum rails Aluminum structural mounts are weather-resistant and continue to look aesthetically
and wind delectors on rooftop mounting systems ofer a considerable weight advantage.
pleasing over time without requiring additional painting or other maintenance.
As a result, with lighter-weight aluminum mounting systems, an engineer can design

and an installer can put more solar panels up to maximize the roof’s square footage by us- Another beneit: aluminum’s lexible design
ing aluminum extrusions for mounts. For elements that move, such as frames in tracking
Increasingly, engineers favor aluminum’s lexibility when designing mounting systems,
especially when it involves extrusions.
hrough the extrusion process, alu-

minum can be formed into intricate
forms and produced to the exact speci-
ications of complicated mounting sys-
tems and other structure components. In

addition, extruded proiles might require
minimal secondary processing and in-
stall faster if proper design techniques
are used.

he design lexibility of extrusions
can’t be overstated. With extrusion, solid
or hollow shapes can be customized to
achieve the ideal structural or functional

purpose. Aluminum extrusions allow
for ininite variations in dimensions and
shape, and can incorporate functional

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SEPTEMBER/OCTOBER 2015
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