2016 Premier Fence

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Solar Energizer Systems
Why your location is important when choosing solar energizers…
ENERGIZERS & SOLAR PANELS 89
A PRS should be close
to vertical—to keep it
perpendicular to the sun’s
rays at 12 noon.
The maps below indicate the hours of summer and winter sunlight available per average day that have sufficient intensity to enable a
12v solar panel to recharge a 12v battery (defined as the hours of solar insolation).
Why is this important?
• Because a solar energizer with the right panel and battery size for New England may overcharge a battery in Arizona, unless it’s
equipped with a voltage regulator. We install such a regulator with each of our PRS energizers.
• Solar panels that are right for Arizona are too small for Vermont—thus reducing battery life by undercharging.
• A solar panel sized for summer usage may be too small for winter. Putting it simply, the same solar unit cannot fit all situations.
That’s why solar farmstore energizers disappoint users so often.
Winter sunlight—(hours available per average day) Summer sunlight— (hours available per average day)
A PRS should be slightly
tilted toward the south to catch
available sunlight. We prop one
edge on top of the ground rod.
Q. Location, season and angle of the
panel appear to be critical factors in
solar energizer success. Why?
A. The maps (below) depict the differing
hours of solar insolation for a region in
winter and summer. Solar insolation is
the hours of sun available per average day
that have sufficient intensity to enable a
solar panel to charge a battery.
Three important things to note:
1. The summer insolation hours
(below) for all areas are much higher
than winter hours. For southeast
Iowa it’s 6 hours in the summer and
less than 3 hours in the winter.
2. The hours available are very
different depending on where you
live. In summer Michigan has 5
hours vs 7.5 hours in Arizona!
3. Ideally the solar panel should be
angled to meet the sun. That means
nearly flat in the summer and nearly
vertical in the winter—and always
facing south.
Q. So why is the identical energizer
sold in Michigan and Arizona?
A. It suits suppliers to keep things simple.
Yes, the panel and battery are
probably too small for Michigan
(except in mid-summer) and too large
for Arizona (except mid-winter). That’s
why many farmstore solar energizers
often fail.
And it’s the extra sunlight in the
Southwest that may damage the
battery in the summer by overcharging
it. (Premier’s PRS units are fitted with
a regulator to prevent this).
Q. What powers a solar energizer at
night and on cloudy days?
A. A DC battery.
All solar units have one inside the
case. The battery must be large enough
to supply the energizer for several
sunless days in a row. (We size ours for
not less than 4 sunless days).
Q. 21 sunless days from a 5 ampere-hr
battery and a 5 watt panel?
A. That’s what a Premier competitor
claims for their 0.5 energizer.
For the same size unit Premier offers
a 12 amp-hr battery, 10 watt panel and
suggests only 4 days. Explanation?
Few things are as misleading. A
normal 0.5 joule energizer consumes
50 milliamperes hr. So 21 sunless days
extracts 25 amperes from a battery.
The misleading unit with 1/5 the
battery and half the panel size reduces
pulse energy as the battery voltage
declines. In a day without sun the
pulse is only 0.25 joules, then 0.10,
then 0.05, etc. Not a pulse that will
stop animals.
Summer vs Winter sunlight…