David answers a letter from a reader about upgrading their van’s 12V system for off-grid travel.
Hey 12V Guru,
I’m not going to buy a new caravan at the moment, but I am doing up the current one so we can head further offroad for longer periods of time. We have a five-year-old Crusader that is in good condition and upgraded the suspension, but we’re now thinking we need more power. What are the key elements we need to know in upgrading the 12V system?
Jim and Shirley Cheesman
Ryan, Qld
—
Hey Jim and Shirley,
Planning an extended off-grid adventure in your RV is exciting, but it also requires meticulous preparation, especially when upgrading your 12V electrical system. Making sure that your RV’s electrics are robust and reliable is crucial for safety and comfort when exploring remote areas. Emergencies aside, there is nothing worse than when you can’t get that coffee machine fired up to kickstart your day. This month we’ve put together a list of critical components you need to focus on to ensure you’re heading off on a well-powered adventure.
Assess your needs: bigger is better!
Start by evaluating your power consumption and considering whether you have been running out of power when travelling. If your current trips are leaving you with about 50 per cent of power each night, consider how many more nights you may wish to spend off-grid at one time and also the location and season. For example, heading to areas that you know are going to be heavily treed will mean less chance to charge from roof mounted solar panels during the day. You should also consider what additional power requirements you need. Are you aiming to power up the air conditioner for a short period of time to cool the van after being in the sun all day or is the hairdryer now super important? This will help you determine the overall energy demand and plan your power accordingly.
Upgrade the battery bank
Your van’s battery bank is the very heart of your 12V electrical system. For extended off-grid stays, consider upgrading to lithium (LiFEPO4) batteries — a popular choice due to their high energy density, long lifespan and light weight. Ensure you have enough battery capacity to store the energy you need, typically aiming for at least 200–400Ah, depending on your usage. While taking up the same amount of space as a lead acid battery bank, a lithium battery will weigh less than half and run for double the length of time.
Solar system
There’s probably not a lot you can do here as most vans sold in Australia are already equipped with two or three panels on the roof and the accessible roof real estate has been filled. Check your power management system as good ones will have an additional input available so that you can add another string of portable solar panels.
Power management system
If you are upgrading your battery bank in either chemistry/lead acid to lithium or increasing the size, it’s likely you’ll need to consider upgrading or replacing your power management system. Contrary to some commentary, lithium LiFePO4 batteries are unlikely to fully charge using a standard AGM charger. Also, if the charger is too small compared to the battery bank, the charger may time out before the battery finishes charging.
Inverter (Pure sine wave)
An inverter converts DC power from your batteries to AC power, allowing you to run household appliances. A 2000–3000W inverter is typically sufficient for most RV setups.
Battery monitoring
Accurate monitoring is essential for managing your power usage and ensuring you don’t over-discharge your batteries. Install a high-quality battery monitor with a shunt, which measures the current flowing in and out of your battery bank. This provides real-time data on battery voltage, current, state of charge, and estimated runtime. Inverters especially can drain battery banks very quickly.
Power on for part two
Upgrading your RV’s 12V electrical system is a significant investment, but it pays off by providing the freedom to explore off-grid destinations with confidence and new levels of comfort. By carefully understanding your power needs and upgrading your battery bank, solar power system and power management system, you can ensure a reliable and efficient power source for your adventures. Of course, you can always rough it and get by but in today’s world you don’t have to — enjoy.
Join us next month for part two of this off-grid preparation topic.
Safe travels,
12V Guru
THE NEXT STEP
If you want to learn the latest caravan news, find the most innovative new caravans and camping gear or get inspired to plan your next adventure to some of Australia's best getaway destinations, subscribe to our weekly newsletter. We promise to send you only the best content.
Related Articles:
Prepare to go off-grid: A guide to power management
Australia’s Ultimate Power and Battery Management Solutions: BMPRO
12V Guru: Upgrading your 12V electrical system | Part 1