Every free camper asks the same question on the second morning: how many days have I actually got before I need to move? Not because you want to leave — because water, power, and gas run down quietly, and the good spots are usually a long way from the next fill. Here’s how to work out your real off-grid runway, and how to make each one last longer.
The three things that end an off-grid stay
Almost every off-grid stay ends for one of three reasons: you run out of fresh water, your battery can’t keep up, or your gas bottle empties. The trick is knowing which one will get you first — it’s almost never all three at once — and that comes down to your capacities and your daily usage.
Water: usually the first to go
Most vans carry 80–150 litres of fresh water. Two people relatively carefully use somewhere around 15–25 litres a day for drinking, cooking, and washing up — more if you’re showering on board. So a 120-litre tank might last five to eight days, not the “a week or two” people often assume. Stretch it by washing up in a tub and reusing the water, taking navy showers or using a solar bag outside, and carrying a spare 10–20 litre jerry for drinking so your main tank is purely for the van. Keep an eye on grey water too — if your grey tank fills before your fresh empties, that’s your real limit.
Power: the one that catches people out
Your 12V battery is the resource most people misjudge, because it depends on the weather. What matters is the gap between what you draw each day — fridge, lights, water pump, charging phones and laptops — and what your solar puts back. On a bright day your panels might cover it entirely; across a run of grey days you’re living off the battery, and lithium or not, there’s a floor you shouldn’t go below. Run the fridge efficiently (keep it full, keep it shaded), switch to LED everything, and treat a cloudy forecast as a reason to be conservative, not a surprise. If you’re regularly waking up to a flat battery, the honest fix is more solar or more storage — but knowing your real day-to-day margin comes first.
Gas: the quiet one
Gas is usually the resource that lasts longest and worries people least — a 9kg bottle can run a fridge, cooktop, and hot water for two to three weeks of typical use — but it’s also the one you notice only when it stops mid-cook. The fix is simple: know roughly how many days a bottle gives you, and carry a spare so a swap is a five-minute job, not the end of the stay.
Stop guessing — let the maths run itself
You can do all of this on the back of an envelope, and plenty of experienced travellers do. But the numbers change every day — a hot spell, a long shower, a cloudy week — and that’s exactly what Ready2Roam’s new Off-Grid Resource Estimation is built for. Set your capacities once, and it turns your real usage into days remaining for water, battery, and gas, right on your dashboard: “≈7 days of water,” “≈8 days of battery in typical sun.” Open the detail view and you’ll see each resource with its usage trend, so you can spot a tank draining faster than usual before it’s a problem, and low-resource alerts give you a nudge while there’s still time to plan a top-up. It won’t fill your tank for you — but it does turn “I think we’re right for a few more days” into a number you can trust.
However you track it — envelope or app — the shift that changes off-grid life is the same: stop finding out you’re low when you’re already low. Know your runway, and the good remote spots stop being a gamble. Ready2Roam’s resource estimation is part of Nomad Pro. See how it works, or download the app free and set up your rig before your next off-grid trip.
