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Mounts for Solar Electric Panels
There literally thousands of mounts,
configurations, and mount options for all the hundreds of various types,
brands, models, and quantity of solar panels. They range from the simple
bracket type mount for putting a panel on an RV, to rail type roof mount
systems, and tracking mounts that follow the sun.
Mounts that we have for
sale at our
online store include Direct Power, Two Seas, Unirac,
Kyocera, Zomeworks.
Types of Mounts
Panel mounts fall into these general categories:
- Flush Mount
- Roof-Ground
- Top & Side of Pole
- Rail Mounting Systems
Flush Mounts:
-
 Flush
mounts are the simplest type of solar panel mount, and are commonly used
for single or small quantities of panels. They are often used on RV's.
They generally consist of nothing more than end brackets or "Z" brackets
that mount to the panel frame and then screw or bolt into the roof.
Despite some disadvantages, these are still the type we recommend for
most RV's and single or two panel roof mounts.
Advantages: Very cheap, simple to install, low wind resistance and weight.
Very common on RV's.
Disadvantages: Not suitable for large arrays, some types of roofs. No flexibility in tilt or orientation. Panels usually must be pre-wired before installing. May be difficult to remove if RTV or other sealant was used on roof.
Roof-Ground Mounts:
 Roof-ground
panel mounts have been the mainstay for many years, especially for off
grid systems. They are less popular with grid tie systems in cities, for
appearance reasons, and because the large arrays often used in utility
intertie solar electric systems can have a pretty high wind resistance.
In extreme cases high winds may cause roof damage. Or worse.
Roof-Ground mounts are called that because they pretty much mount either on a
roof or on the ground with little or no change in mount setup. All provide some
kind of tilt, either adjustable or fixed. In very high wind
areas they require a good anchor point or they tend to blow away, and
that is not usually a good thing.
Roof-ground mounts are simple to install, but in some cases it is preferable to
mount the panels first if you are mounting them directly on the ground, as the
lower row of panels in multi-tier rack can be hard to get to. Many people raise
them up a few feet by setting them on short poles, concrete blocks, or steel
feet. This also keeps them up high enough so you don't get any panel shading
from weeds or grass growing nearby. Advantages: Relatively inexpensive, fits a wide variety of panels.
Can be used almost anywhere - even on the side of buildings. Most are available
with adjustable tilt for the best sun angle to produce the
best power. However, tests done by
Sandia
Labs show that you only get about a 5% increase over a year by adjusting the
tilt every 3 months.
Disadvantages: May require heavy earth or roof anchors in some areas
with very high winds. May be less than esthetically pleasing (that means
ugly) in your back yard. Some city codes may have limits or restrictions on roof
structures and/or visibility.
   Pole Mounts:
This includes Top-of-Pole, Side-of-Pole,
and Tracking Mounts for solar panels.
Pole mounts, especially top-of-pole, have been popular for a long time.
Top-of-pole mounts are essentially a steel or aluminum rack and rail system
bolted or welded to a large sleeve that sets on top of a pole with set-bolts to
keep in place. Side-of-pole mounts are often used when you need to mount to the
side of a telephone pole or communications tower. Tracking mounts are similar to
top-of-pole mounts, but they also have a method of automatically aiming
the mount to follow the sun.
Zomeworks and
Wattsun are the two major manufacturers of tracking mounts. Both have
a wide variety of sizes available. Wattsun sells a 2-axis (tracks both
vertical and horizontal), but in our opinion they are not cost effective -
stick with the single axis type.
Top of pole mounts (including trackers) are one of the simplest (but not
always easiest) of mounts to install. They essentially only need a single steel
pole set in the ground (usually in concrete), and the mount slips onto the top
of the pole. Most common sizes use a 2-inch to 8-inch pole, usually around 11 to
13 foot in length (11.5 foot is 1/2 of a standard 21 foot pipe). They can go
higher - most commonly where you need to get the panel up more to avoid shading
from nearby shrubs, or to keep animals such as cows and elk from using them for
a scratching post if not fenced off. Several companies manufacture top and side of pole mounts, including
Direct Power, Two Seas, Zomeworks, and UniRac. Most have a wide variety of
types to fit nearly any current solar panel. Our available mounts are listed on our
online store.
There may be two hard parts to actually installing them - larger mounts will
require a good anchor, which can mean in soft soil that you may have to dig a
hole as much as 7 foot deep to avoid them being turned by the wind. The second
is that large mounts can be very heavy, so you will need either a small crane,
gin pole, or a few people to lift it up. One advantage of top of pole mounts is
that they are very easy to wire up, since the back of the panels is easily
accessible. We usually recommend that you do not mount the panels before getting
the mount on top of the pole, especially for larger sizes. If something drops,
you could have a smashed panel disaster. Rail Type Mounts
under construction
General Mounting Information
Roof Mounting Clearance: Panels mounted on a roof
should have at least an inch, and preferably 2 to 6 inches, clearance between
the bottom of the panel frame and the roof. This allows for air flow under the
panels for cooling. Panels should never be mounted so there is no air flow under
them, as they can reach very high temperatures that way, just like car parked in
the sun. |
