Which Solar Energiser is best for a 200m kit?

When you’re looking for a solar energiser for a large electric netting set up the same basic principles apply – namely where do you live and what are your expectations?

To work out which solar energiser suits your requirements, we need to know when and for how long you intend to use the energiser as well as how the electric fence fits into your overall flock protection plan. For example, are you running the energiser 24/7/365 and is it the sole line of defence between your flock and predation? Or is this just a weekend / hobby thing and the flock is securely locked away every single night?

A quick note on energiser capacity – energisers are measured in “Output Joules” (J). A 200m set requires an energiser with a minimum of 1.2J, 300m around 2.0J etc. You can always put more power than you need into an electric net but you cannot put less. Another way of looking at this would be to say – regardless of where you live or what your expectations are, the power level you require remains the same, what changes is the size of the battery and the solar cell.


1. Energiser options for 24/7/365 Operators in Southern Australia

The big issue here is that you will need sufficient solar cell wattage to charge the battery all year round – especially during the winter months. For example, if you live in an area that gets about 4 hours of Sunshine per day in June (primarily VIC and TAS) then you will need an absolute minimum of a 20W solar cell to get a 1.5J energiser powering a 200m electric net through the winter (this would be a marginal case).

(Just a quick diversion here – a solar energiser which comes in one box and all the bits are molded into one piece is called an “integrated” energiser. Bigger energisers where you purchase the battery separate from the energiser separate from the solar cell is called a “custom build”)

So, since you will need a 20W solar cell to get through the winter you are immediately in the realms of custom build sets as no integrated set comes with a 20W solar cell. The best value custom sets are made by JVA, but if you want more features and options then Thunderbird on Nemtek provides options.
For the battery your best option is to purchase one from your local battery dealer. The bigger the battery you purchase the longer it will last in poor weather conditions. I would recommend that a 100Ah battery would be the minimum requirement.


2. Energiser options for 24/7/365 Operators in Northern Australia

If you live in an area that gets more than 6 hours of sunshine per day in June (roughly north of the line from Coffs Harbour to Geraldton) then you can reduce either your solar cell or your battery but not both. You will need the same size energiser however as you are still powering the same length net.

So the sensible thing here would be to reduce the size of the solar cell and keep the same size battery.

(Another aside – There are some big integrated sets that would do the job here (in terms of sufficient power output) but the problem is that they do not come with big enough batteries. For example the Thunderbird S185B puts out 1.8J but only has a 12W solar cell and a 14Ah battery. This means you would need a minimum of 8 hours of daylight per day which is only available in the NT in winter).


3. Energiser options for Hobby Operators in Southern Australia

For the purposes of this article I am going to assume that a “Hobby Operator” only uses the net in the warmer months of the year (say September through to April) or locks their flock indoors at night and turns off the energiser.

The big advantage that “Hobby Operators” are going to have over the “24/7/365” crew is that the hobby operator can turn off the energiser at night during the winter months which effectively doubles battery capacity. Therefore some of the integrated solar energisers start to become an option.

You are still going to require an energiser with an output over 1.2J, which means we can look at integrated sets such as the Thunderbird S185B or “semi-integrated” sets such as the Thunderbird S340 or Nemtek Agrisolar 25. (Semi-integrated means the solar cell and the energiser are one unit but you need to provide your own battery). The Thunderbird S340 has a 25W cell, the Nemtek Agrisolar 25 has a 20W cell and the Thunderbird S185B has a 12W cell.


4. Energiser options for Hobby Operators in Northern Australia

By and large the same rules apply in Northern Australia for hobby operators. Having the ability to turn the energiser off at night makes roughly halves the amount of battery or solar cell capacity required so the integrated or semi-integrated kits become a real option although any energiser bigger than this will also do quite nicely.


My recommendations.
What I am going to do here is try and make an educated guess and rank all energisers on the market that fit in the 200m to 400m electric netting sizes. I will rank firstly by capacity, taking note of the solar cell and battery capacities and then price.



200m minimumThunderbird BLK12S Solar Energiser

★ Thunderbird 12S. This is a basic energiser with a 1.2J capacity. Therefore it will power 200m of netting, but it has limited battery and solar cell capacity. The biggest drawback is that it does not have a mains charger – therefore if the battery runs flat the only way to recharge it is to leave it sitting in the sun for a few days – not ideal in winter. However, if you only use the net for a few days at a time and in the warmer seasons it should work fine.

★ JVA MB1.5 Solar. Puts out a charge of 1.5J which also puts it in the 200m of netting category. This is a nice simple system with a 20W Solar cell but you will need to supply your own battery. Pair it with a big battery and the 20W solar cell should be able to get a 200m electric net powered throughout the year in all areas other than the South. The main downside is that it has no battery condition lights or a display to indicate output levels.


250m minimum

★ Thunderbird S185B. This is the biggest integrated solar energiser on the market. It puts out 1.78J and therefore can handle up to 250m of netting. You can switch between high and low output functions. It has a digital screen which displays voltage, amps and low battery. It also comes with a mains charger so if you do run the battery flat you can bring it inside for a top-up charge. It has a 12W solar cell and a 14Ah battery. This makes it a good option for summer operations but not for winter especially the further south you get.


Over 300m

Nemtek Agrisolar 25km Energiser panel and control
★ Nemtek Agrisolar 25. This energiser puts out 2.3J putting it in the 300m of netting category. It comes with a 20W solar cell and can be programmed for independent day / night settings(programmer costs extra).

JVA MB3 Electric Fence Energizer with 50W Solar Kit

★ JVA MB3 Solar. Comes with 3J of output and a 50W Solar cell. Like all JVA systems it comes with a lot of grunt but no bells and whistles – so no battery indicators or programmable functions etc. The 50W solar cell is big so pair it with a big battery and you have a powerful system. Probably a good idea to purchase a fence tester at the same time .JVA MB4.5 Electric Fence Energizer with Solar Kit

★ JVA MB4.5 Solar. Output of 4.5J and a 50W Solar cell. So a very powerful unit with a lot of recharge capacity but no fancy bits. All else being equal unless you need the extra capacity you would be better off with the JVA MB3 as all the extra capacity will do is drain your battery faster (because the solar cells are the same).

Nemtek Agrisolar 50km Energiser panel and control

★ Nemtek Agrisolar 50. Puts out a charge of 4.6J and does require the purchase of an external battery. Solar cell is 40W and also has day / night programming options (programmer costs extra).

JVA MB8 Mains Battery Electric Fence IP Energizer Solar Kit

★ JVA MB8 Solar 8J of output is big enough for any netting set-up. The MB8 comes with a 100W solar cell.


1. Don’t just choose the biggest! An energiser with twice the output will also drain the battery twice as fast. So if your fencing set up requires 1.5J in order to function, choosing an energiser with an output of 2J to 4J might make sense but 8J is a bit silly.

2. Choose JVA products if you just want something simple and cost effective. There are no indicator lights so you should purchase a fence tester at the same time.

3. Nemtek products are for people who want to set up the system to suit their needs. Fully programmable with separate day / night operations, output levels and pulse rates. Multiple indicator
lights and the works.

4. Thunderbird is best if you just want to take it out of the box and not lug batteries around.