Photo-voltaic Panel Technology:
Sun Hours/Day Zone Solar Map
Mono-crystalline, or Single Crystal Cells:
Also known as the original PV technology,
was invented in 1955 , and never known to
wear out. These single crystal modules are
composed of cells cut from a piece of
continuous crystal. The material is formed
into cylinders which are sliced into thin wafers
which can be installed in their circular form to
minimize waste or can be trimmed to a desired
shape for installation. PV experts generally agree
that the crystalline silicone form of cell is the premium
technology for critical applications in remote areas.
Thin Film Panels:
This form of panel can be made light weight by
using flexible, plastic glazing. Some of these types
of panels can tolerate a bullet hole without failing.
Some forms of this panel perform slightly better than
crystalline panel modules under low light conditions.
The disadvantage of thin film technology are lower
efficiency and uncertain durability. This means more
space is required and also requires more mounting hardware
for the additional panel coverage required. They
also tend to be less stable than crystalline and degrade
over time causing shorter life spans for the installation.
National Average Hours (Over the course of the year)
ZONE 1 - 6 hours
ZONE 2 - 5.5 hours
ZONE 3 - 5 hours
ZONE 4 - 4.5 hours
ZONE 5 - 4.2 hours
ZONE 6 - 3.5 hours
Average: 4.4 hours
This form of panel entered the market place in 1981
and are made from similar silicon material as the
Mono-crystalline panels except these are melted and
poured into a mold of a specific shape. As the material
cools, it crystallizes in an imperfect manner forming
random crystal boundaries. The efficiency of energy
conversion is slightly lower which requires the finished
module be slightly larger per watt. The irregularity in the
crystal structure produces variations of blue which give
the appearance of a gemstone, which can be quite
nice aesthetically speaking.
Photo-voltaic Panel Technology:
Panel Mounting Options:
There are several options for mounting of PV array’s at a residence.
A typical 2 Kilowatt PV system requires 200-400 square feet of unobstructed
area to site the system. An additional 20% of area is needed for access
to the mounting area and the installed system. The added wight of a PV
array is typically 3-to-5 lbs./sq. ft. so this needs to be accounted for with any
existing or new structure prior to installation of the system array.
Often the most convenient and appropriate place for installation of the
PV system. The system may be mounted above and parallel to the
roof surface with several inches of standoff for cooling purposes.
With flat roof systems, additional structure is sometimes required to
achieve the optimal tilt angle of the installed panels.
When applied to masonry style roof systems, additional structural
support may be required since the roof system has been designed
near the limit of its weight-bearing capacity.
As an alternative to roof mounting, this system is installed as a
shading structure such as in a patio cover. The construction cost
for such a system can vary depending on the amount of shading
desired and the angle at which the system is to be installed.
If the PV system is at a steeper angle that what the shading device
calls for, then additional structural elements would have to be
installed. With the shade structure location, some of the installation
cost could possibly be traded off with less mounting hardware and
associated installation labor. Although the overall cost for such
an installation may be more than the roof mount option, but the
of the shade element may be the determining factor for such.
Other issues that should be considered with this type of installation
Simplified array access for maintenance.
Module wiring installation needs planning and implementation
for visibility issues.
Day to day maintenance issues such as vines and other
vegetation growth have to be addressed for optimal
Additional factors that affect Photo-voltaic arrays.
Additional factors that have to be taken into account when determining the
efficiency of the Photo-voltaic system include temperature, dirt and dust
accumulation, mismatch and wiring losses, DC to AC conversion losses, failure of
wiring systems due to unforeseen or outside intrusion and weather.
The installation has to be maintained, cleaned and surveyed for possible problems
on a set basis. This may be annually on a month to month basis for some items where
others may be on a yearly basis. Good maintenance practices are the key to the
most potential in any system and should be scheduled and adhered to.
Animal intrusion should be addressed in a timely fashion if it should occur to keep
costly repairs to a minimum. Require of the installation company or at a minimum,
the manufacturer, information about warranties and service agreements. Most
often, a good service contract is a great way to get the full benefit of the
installation with the least amount of additional cost to the home/business owner.
Ask questions up front before you sign a contract, once you agree to the scope
of installation, it is difficult and costly to amend or change such contracts.
Orientation of the structure and the sun angle plays a big part in the total
efficiency of the installation. During the day, the angle of sunlight striking the
solar module will change and has an affect on the total power output of the
system. The output from the system will rise from zero during dawn hours and
increase with the sun angle to its peak output at midday and then gradually
decrease into the afternoon and back to zero at night. Placement and location
for optimal solar usage is key to a successful installed system and should be
carefully considered prior to installation. Area of coverage, the sun angle and
the pitch of the roof play an important part in the efficiency of the installation.
See chart for more information:
Integrated Roofing Installation
Building-Integrated PV array systems (BIPV):
This type of system displaces the conventional roofing materials that
we typically associate with the building process and is installed in
these locations. Commercially available products that are currently
available include Roof Slates (similar to masonry roofing) and
standing seam metal roof products. These installations required
special attention to insure that these elements are installed properly
and meet the necessary fire ratings for local codes and ordinances
governing the type or scope of construction. With this type of
installation, dimensional tolerances require strict adherence and
manufacture installation instructions must be followed precisely to
remove possible conflicts, roof leakage and installation failure.
Photo-voltaic Panel Technology:
Examples of Specific PV system capabilities:
Estimated system cost:
(in watts per hour)
Monthly Output Capability:
(based on 5 hours of direct/
insolated sunshine per day)
(before tax incentives
RV Systems Installation
These figures are based on a complete solar power system installation installed by
a specific installation company (Wholesale Solar). Other companies prices may
vary and based on location and other factors. Prices as shown are approximate
as of August 2012 and may vary from what is shown. Prices do not include freight,
taxes, racking systems, installation of axillary add on items such as battery
back-up or purchase price of these item.
Federal Tax Credits:
Tax credits have been extended till 2016 and the new FTC will take effect as of
January 1, 2009. (Check with your tax advisor for current conditions)
For homes and commercial businesses, it covers solar hot water and solar electric.
It does not cover solar pool heaters.
For both residential and commercial, you get 30% back with no cap.
Check with you tax advisor for proper forms and information that are required to
accurately report these systems to the IRS.
In the state of Louisiana, Contact (http://www.LSES.org) for more information about
solar energy and the possible tax credits possible.
Residential Installation (Japan)
Other Alternative Energy Programs:
Individuals are encouraged to contact other agencies such as “HELP - Home
Energy Loan Program” for available financial help in purchasing and installing
alternative energy sources for their home of place of business.
System mounting blocks:
( Element as shown mount
to structure with roof
insulation surrounding block)
(panels mount directly to
rail which is mounted on
racking system structure)