How Much Power Do You Need?
Choosing the Right Energiser for Your Electric Fence
Choosing the right energiser for your electric fencing is crucial for effective livestock management. Whether you're new to electric fencing or looking to upgrade your system, understanding the differences between solar, battery, and mains-powered energisers is essential. In this blog, we’ll break down the options, explain how to calculate the right power (joules) for your needs, and offer top tips for setting up a reliable system.
Solar vs. Battery vs. Mains-Powered Energisers
Solar Energisers
These self-contained energizers feature an integrated solar panel and a sophisticated battery management system in a sturdy carrying case.
Solar-powered energisers are increasingly popular due to their environmental benefits and cost savings over time. They harness energy from the sun to charge an internal battery, which powers the fence.
Pros:
Eco-friendly: Solar power is renewable, reducing your farm’s carbon footprint.
Cost-effective: After the initial purchase, running costs are minimal as you rely on free solar energy.
Portable: Ideal for remote areas where mains power isn’t available. Smaller models up to 2J are very portable and great for temporary or rotational grazing systems where fencing might need to be moved.
Cons:
Weather-dependent: Less effective in areas with limited daylight during winter months.
Initial cost: Higher upfront investment compared to battery or mains options.
Best for: Fields in remote areas, especially if mobility is important.
Battery-Powered Energisers
Battery energisers are portable, running off replaceable or rechargeable batteries. They offer flexibility and are easy to set up.
Pros:
Portable: Great for temporary or rotational grazing systems where fencing might need to be moved.
Easy to install: No need for mains electricity or solar panels.
Cons:
Ongoing cost: Batteries need regular replacement or recharging, adding to running costs.
Lower power output: Often less powerful than mains energisers, making them unsuitable for long or heavily vegetated fences.
Labour output: Batteries can be heavy and require regular attention, including remembering to recharge or replace them with new ones.
Best for: Small to medium-sized farms or where fencing needs to be frequently moved.
The Speedrite 46000W Mains Energizer is a powerful model, for farmers that want a great performing energizer with an intuitive interface. With Bluetooth and Wi-Fi compatibility, the Datamars Livestock Farm App provides the ability to monitor and control the energizer from a phone.
Mains-Powered Energisers
Mains energisers connect directly to your farm’s electricity supply, providing a consistent and reliable power source.
Pros:
Powerful and reliable: Delivers consistent energy output, suitable for longer fences and heavy vegetation.
No ongoing battery costs: Once installed, there are no ongoing costs beyond electricity usage.
Cons:
Location-dependent: You need access to mains electricity, which can limit placement options.
Installation: Requires more permanent installation and initial setup compared to battery or solar options.
Best for: Larger farms with access to mains electricity, particularly where fencing is permanent or semi-permanent.
How to Calculate How Many Joules You Need
To determine the correct power output (in joules) for your electric fencing, follow these steps:
Calculate your fence length: Add up the total length of your fence in metres. This should be the ground distance covered, not the number of wires on the fence.
Adjust for wire type and vegetation: The type of wire and the amount of vegetation around your fence affect how much power is needed. Multiply your fence length by:
x2 for high-tensile wire with no vegetation
x3 for high-tensile wire with vegetation
x10 for polywire, which has higher resistance
Convert to kilometres: Once you’ve adjusted for wire type and vegetation, convert your total fence length from metres to kilometres (1,000m = 1km).
Calculate joules: Divide the total adjusted fence length by 10km. The result is the minimum number of joules your energiser needs to deliver. For example, if your fence length totals 7 kilometres, you would need at least 0.7 output joules.
Consider wire resistance: The more wires on a fence, the lower the resistance, which can improve the fence’s efficiency. However, additional wires often increase the chance of contact with vegetation, which can counteract the benefits of lower resistance. To make the most of multi-wire fences, join the wires at both ends for optimal conductivity. We offer line-to-line connectors and triple jumper leads on our website, or you can use spare wire to achieve this.
It’s a good idea to size up your energiser to accommodate potential future expansions or higher challenges, such as heavy vegetation or untrained livestock. Opting for a larger unit now could save you time and money in the long run.
Other Equipment for a Good Electric Fencing System
Makes fence maintenance easy. The combined voltmeter and current meter is designed for the rapid location of electric fence faults.
In addition to your energiser, there are other essential components to ensure your electric fencing works optimally:
Quality wire: Use high-tensile wire or polywire for the best conductivity.
Posts: Choose sturdy posts to keep the fence taut and reduce sagging.
Insulators: Ensure you use good-quality insulators to prevent energy loss where the wire touches the posts.
Earth stakes: A good earth connection is essential for your fence to function properly. Use multiple stakes if necessary to improve grounding. See options here.
Fence tester: Regularly test your fence, especially after storms or heavy vegetation growth. For sheep, aim for a minimum of 6,000V, and for cattle, at least 5,000V. With a well-powered fence and good paddock design, animals will see the fence as an unbreakable barrier and won’t challenge it, reducing the impact of any voltage drops. See options here.
Top Tips for Setting Up a Reliable System
Regular maintenance: Check the fence line regularly for any breaks, shorts, or overgrown vegetation that could drain power.
Invest in quality: It will save you time, hassle, and replacement costs in the long run. We stock Speedrite and PEL energisers because of their reliable quality and power output. Plus, with a 7-year warranty, these brands demonstrate the confidence they have in their products.
Plan your layout: Think about where the energiser and earth stakes will be positioned to maximise efficiency and minimise the risk of power loss.
Training livestock: If your animals are new to electric fencing or haven’t encountered one for over five months (such as after winter housing), it’s important to train them to recognise and respect the fence. Follow our 5-step guide for a low-stress, effective approach to training: How to Train Livestock to Electric Fencing.
Conclusion
Choosing the right energiser for your electric fencing is key to effective livestock management and security on your farm. Whether you opt for solar, battery, or mains-powered options, ensure you’ve calculated the correct power (joules) needed for your specific situation. With the right setup and regular maintenance, your electric fencing system will be a reliable and cost-effective tool for years to come.
Looking for the best energisers on the market? We stock a range of high-quality energisers suitable for all farm sizes and needs. Get in touch to learn more or shop our selection today!
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