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PV Design software: where can I find It?
I am trying to locate a good solar photovoltaic (PV) design software package for my install business. There are plenty on Google search, but [I’m] not sure ven where to start. Thought you could help or lead me in the right direction.
— Steve Schanne, Woodbury, N.J.
— SCOT T SkLAR,
president of the
Stella Group (thestella
groupltd.com), a solar
consulting firm in
Joseph McCabe, chair of the American Solar Energy Society (ASES)
Solar Electric Division, offers these
•;PV-DesignPro at mauisolarsoft-ware.com.
•;PVsyst ( pvsyst.com/5.2/index.
php) is a software package for the
study, sizing, simulation and data
analysis of complete PV systems.
• Precigeo ( precigeo.com) uses
aerial imagery and computer-aided
design to provide shading evaluations, individual module
selection with custom placements along with fire setback
— JOSEPH MCCAbE,
chair of the American
Solar Energy Society
Scott Sklar, president of the Stella Group (thestella
groupltd.com), a solar consulting firm in Washington,
•;3Tier’s website ( 3tier.com) to gauge the solar resource.
•;NREL’s;PVWATTS ( nrel.gov/rredc/pvwatts/).
•;Sandia National Laboratory’s
guide ( photovoltaics.sandia.gov/
•;In My Back yard, a solar and
wind tool ( nrel.gov/eis/imby/
For more sophisticated energy-
modeling software, useful for
architectural and engineering
firms, the popular programs
•;Homer ( homerenergy.com/software.html) and
•;Energy 10 ( nrel.gov/buildings/energy10.html).
Sklar also recommends —
• The Solar Design Tool ( solardesigntool.com/user.
• Sustainable by Design ( susdesign.com/tools.php).
Find a useful directory listing dozens of software packages
Portable PV system: Is It worth the money?
Alocal store sells a small, 60-watt solar system for $312, with inverter — you just need to add
a battery. Is it worth it? — Terry Trefz, Cardington, Ohio
submit them to
Not all questions
can be answered
That’s about $5.20 per watt, more
or less competitive with other
photovoltaic (PV) systems
on the market. “Small
photovoltaic systems do
make sense for remote
and portable use,”
says Scott Sklar. “The
60-watt panel with inverter
and a battery could be useful in charging portable tools, cellular phones and
video games, for running the fluorescent
or CFL lights in a shed or garage, or for
camping, where it could inflate tires, provide light and run a radio.”
Joseph McCabe says, “Typically, smaller
solar electric systems are more expensive
per watt than larger systems — check on
computer-portability and camping-supply
websites to see if this price is fair. Do consider how fragile the panels are; often times,
amorphous silicon on float glass will break
more easily than crystalline silicon on tempered glass. Do be sure to include a charge
controller to interact with the battery charging from the solar panels. Direct-current
charge controllers can be cost-effective,
even for smaller systems, optimizing the
power harvest from the panels and protecting the battery for longer life.” ST
66 November/December 2010 SOLAR TODAY solartoday.org
Copyright © 2010 by the American Solar Energy Society Inc. All rights reserved.