We seem to get a lot of confusion from our users as to how solar electric fence energisers work and function,why they are used and what is the best energizer to choose for your fencing.
What is a solar electric fence energiser
Essentially a solar electric fence zapper is a battery operated energiser that uses a solar panel to top up the battery used to power the energiser.
So a solar energiser consists of 3 major parts:
Generally a battery energiser used in a solar set-up will be a 12volt energiser. There are some solar electric fence energisers that run off other voltage.
The battery will need to match the power input required by the energiser, so if you are you are using a 12 volt battery energiser you will need a 12 volt battery. The storage size (measured in AH or amp hours) of the battery should be big enough to last for 1 week without any sun to charge the battery, to calculate this you will need to find out how much energy the energiser uses and compare that to the batteries available to you. Any Good battery supplier should be able to help you work this sum out.
solar charge regulator
The solar panel is used to charge the battery and keep it topped up so it can run day and night, rain or shine.
The solar panel also needs to be matched to the energiser as it is the energiser that dictates how much energy will be used. As a general rule you will need about 10watts of solar panel to every 10 kilometers your energiser claims to fence. As an example a 2km energiser will require a 2watt solar panel.
Any solar panel over 2watts should be fitted with a charge regulator. This will stop the solar panel from over charging the battery and stop reverse flow of electrons when the panel isn’t charging the battery (night time).
Why should you use a solar energiser
Solar energisers are generally used in remote locations where there is no mains power (240v 50Hz in Australia) or when there will be nobody around to keep an eye on the charge level of the battery that is supplying the power to the energizer.
If you live in areas that are prone to lightning strikes, solar energisers are recommended. Lightning is far less attracted to a solar unit than an energiser connected to mains power. This is more than likely due to the fact that the solar energiser is not connected to a larger earth supply than a mains powered fencer. Lightning will more often than not take the easiest or best path to earth it can.
Why not use a solar energiser
If you can use mains power to run your energiser by all means do so. The cost both in running the energiser and in initial purchase price of the unit is far cheaper than a solar alternative. solar energisers cost on average at least twice as much to purchase and if you need to replace the battery every couple of years the operating costs can be far more significant than a mains powered unit.
Facts and fiction about solar energisers
One misconception is that the energiser runs off the solar panel. While that is possible the fence would run out of power as soon as the sun is gone or there is not enough light to supply the required voltage to the battery energiser (usually over 12 volts).
Solar energisers aren’t as powerful as other energisers…This is not true just because there is a solar panel involved does not mean the energiser is any weaker than other energisers. It is not the panel running the fence it is the battery, all the panel is doing is keeping the battery topped up.
Electric fence manufacturers more often than not charge crazy prices for solar panels. I don’t know what it is about this industry (I think they all live in the past) but for some reason one company charged prices like it was made of gold and the rest of them followed suit. In this day and age solar panels are not that expensive and if you do your research right you can make your own solar energiser for a fraction of the cost while still using quality products.