Independent guidance for 12V installs.
Size your cable, work out your battery capacity, or find a specialist installer near you.
Whether you’re a DIY enthusiast or a professional installer, our resources will help you harness the potential of 12V power systems. From understanding battery types to learning about solar power integration, we aim to cover everything you need to know. Additionally, our guides provide tips on selecting the right components, ensuring safety, and optimising performance. Explore our library of articles that delve into the intricacies of 12 volt systems, including installation techniques, troubleshooting advice, and maintenance tips. By utilising our calculators, you can accurately determine your power needs and make informed decisions.
What makes up a 12V off-grid system
Nearly every off-grid setup comes down to four parts: a battery that stores the energy, a charging source that puts energy back in (alternator, DC-DC charger, solar or mains), the cable and protection that move it safely, and the loads that use it. Size each part correctly and the system looks after itself. Get one step wrong, and it is usually the cable or the circuit protection, and the whole system becomes unreliable or unsafe. Our guides work through each part to help you get it right the first time.
Choosing a 12V battery
Battery choice comes down to three numbers: usable capacity, charge acceptance and weight. A 100 Ah AGM gives you about 50 Ah you can actually use without shortening its life, weighs around 30 kg, and will not accept a fast charge from a modern DC to DC unit. A 100 Ah lithium gives you about 90 Ah usable, weighs around 12 kg, and will take everything the charger can give it. That is why lithium wins in a touring build even at two to three times the price, and why AGM still earns its place in a standby bank that sits at full charge most of its life. Work out what you need before you shop: the 12V Battery Calculator turns your daily load list into a usable capacity figure.
Adding solar to a 12V system
Solar is the easiest way to stay out longer and the most commonly oversized part of a 12V system. As a rough guide in Australian conditions, a fixed panel returns around three to four times its rated wattage in watt hours across a good day, so a 200 W panel gives you roughly 600 to 800 Wh, or about 50 to 65 Ah at 12V. Shade, panel angle and winter sun cut that hard, and a panel flat on a roof gives up more than most people expect.
An MPPT controller earns its extra cost once you are past about 100 W, or any time panel voltage sits well above battery voltage. Size the battery first, then size the array to replace what you actually draw, not what the panel is rated at.
Solar Power Integration
Integrating solar panels into your 12V system can significantly increase your energy independence. Solar panels convert sunlight into electricity, which can charge your batteries or power your devices directly. Our site will discuss how to size your solar array, the importance of MPPT (Maximum Power Point Tracking) controllers, and the benefits of having a hybrid system that combines solar power with vehicle DC to DC charging.
Getting it Installed
Plenty of 12V work is well within reach of a careful DIYer. Some of it is not. Anything that ties into the vehicle’s charging system, any fixed 240 V wiring in a caravan or camper, and any work around gas or battery compartments is worth handing to someone who does it every day and can certify it. If you would rather have it done properly the first time, the directory lists 12V installers across Australia by state, category and service type, including mobile operators who will come to you. We also have a list of 12V Power Specialists to help you when you need it.