The Honest Answer (No Fluff)
How much solar do I need for a Big Lap of Australia? Most modern touring setups now run between 800W and 1200W of total solar, usually paired with 400–600Ah of lithium battery capacity. The right amount depends on how long you camp off-grid, what appliances you use, and whether air conditioning is part of your setup.
There isn’t a single number that works for everyone.
How much solar you need for a Big Lap of Australia depends on:
- How long you stay off-grid
- What you run every day
- How much shade you camp in
- Your battery capacity
- Whether you move regularly or sit still
If you’re hoping I’m about to tell you “get X watts and you’re sorted”… I’m not.
Because after living on the road and watching what other Big Lappers actually run, I’ve learned this:
Solar isn’t a number. It’s a lifestyle decision.
That’s why blanket advice like “400–800W is plenty” no longer holds true for many modern touring setups.
Quick Reality Check
What I see on the road most often now is this:
Most Big Lap travellers are running around 800W to 1200W+ total solar, often with roof panels plus a portable solar blanket.
And if people are running any mix of:
- air conditioning
- Starlink
- induction cooking
- big inverters / 240V appliances
- long off-grid stays
…they usually need more solar and more battery than they expected.
And no, it’s not because they’re “doing it wrong”. It’s because touring setups have changed. We’re travelling with more comfort gear than we did years ago.
Who This Guide Is For
This guide is for you if:
- You’re considering air con or other high-draw appliances
- You’re planning a Big Lap or long-term touring
- You want to free camp regularly, not just overnight stops
- You’re confused by watts, amps, batteries, lithium, and all the solar chatter
- You don’t want to overspend, but you also don’t want to underbuild and regret it later
From The Road: What We Actually Run
For context, here’s what we run on our own van:
- 4 x 210W roof panels (840W total)
- 2 x 200Ah lithium batteries (400Ah total)
- 400W EcoFlow solar blanket (and yes, we treat it as essential)
With this setup, we can comfortably stay off-grid indefinitely in normal conditions. In fact, we usually run out of water before we run out of power.
But that’s assuming:
- We’re not dealing with extreme heat
- We’re not trying to run air con constantly
- We’re managing usage sensibly
If I was building again, I’d put as much solar on the roof as physically possible and increase battery capacity.
Not because this setup doesn’t work, it does.
But solar is easiest to add during the build, and extra battery capacity reduces mental load. You rarely regret building margin into your system. You do regret building “just enough” and constantly watching your power levels.
The Biggest Mistake People Make With Solar
Most people start with solar watts.
That’s backwards.
Solar doesn’t create power on demand. Solar replaces what you use, and only when the sun cooperates.
This is the real equation:
Daily usage → Battery capacity → Solar input → Sun exposure → Travel style
If one of those is out of balance, you’ll feel it fast. Even if you’ve got panels covering half your roof.
What Actually Uses Power On A Big Lap (real-world stuff)
Here’s what we see most often on the road.
Everyday Power Users
- 12V fridge (sometimes two)
- Phones, iPads, cameras
- Laptops (especially roadschoolers and remote workers)
- Lights
- Water pump
- Fans
Common High-Draw Extras (the “this adds up” list)
- Starlink
- Coffee machines (yep)
- Inverters powering 240V gear
- Induction cooktops
- Air fryers
- Diesel heater fan (small draw, but runs for hours)
The Big One: Air Conditioning
Air conditioning changes everything.
Once air con enters the mix:
- Solar requirements jump dramatically
- Battery storage becomes just as important as panels
- You must plan for overnight draw, not just daytime charging
There’s no sugar-coating this: anything that heats or cools (air con in this case) is a power-hungry luxury off-grid.
Real-World Solar Setups (what I see working)
1. Touring With Movement (Most Big Lappers)
If you move every few days and camp off-grid regularly:
- Roof solar: 800W–1000W
- Portable solar blanket: 200W–400W
- Battery storage: 400–600Ah lithium (minimum)
This tends to cover:
- fridge(s) running 24/7
- normal device charging
- flexibility when you’re in partial shade
- “catch-up” capacity after cloudy days
This is the sweet spot I see over and over for people who want comfort without turning power into a full-time job.
2. Long Off-Grid Stays (5+ Days In One Spot)
f you love a good free camp and you don’t move often:
- Roof solar: 1000W–1200W+
- Portable solar blanket: essential
- Battery storage: 600Ah–800Ah lithium
Why? Because once you stop moving, you often lose alternator charging as your backup plan. You’re relying on the sun to shine and no clouds.
Portable solar becomes the difference-maker because you can:
- park in shade and still chase the sun
- recover after cloudy days
- avoid firing up a generator (if you’re trying not to carry one)
3. Off-Grid With Air Conditioning
This is where expectations need to be realistic.
If you want to run air con off-grid, you need to be realistic:
- Solar alone doesn’t “run” air con
- Solar charges the batteries.
- The batteries feed the inverter.
- The inverter powers the air conditioner.
A typical setup looks more like:
- 1600W–2000W+ total solar
- 800Ah–1200Ah lithium
- strategic air con use (daytime, short bursts, or only when conditions allow)
Running air con all night, every night, purely off-grid is still unrealistic for most people unless they’re spending serious money and weight allowance.
If We Built Again…
If we had our time again?
I’d put as much solar on the roof as physically possible and increase battery capacity.
Not because our system doesn’t work. It does.
But solar is easiest and cleanest to add during the build. Retrofitting later is always more complicated, and battery upgrades are rarely cheap.
What I’ve learned from being on the road:
- You never regret extra roof solar.
- You rarely regret larger battery capacity.
- You do regret building “just enough” and constantly watching your power levels.
The more margin you build into your system, the less mental load you carry while travelling.
And when you’re doing a Big Lap, reducing mental load is worth a lot.
Roof Solar Vs Portable Solar Blankets (The Truth)
This isn’t either/or.
Roof Solar
Pros
- works while driving
- no setup
- reliable baseline charging
Cons
- shade kills output
- fixed angle
- harder to add later
Solar Blankets
Pros
- you can chase the sun
- you can park in shade (huge in Australia)
- easy way to add capacity without roofing work
Cons
- setup and pack-down
- theft risk if you walk away
- needs space to store
The Best Setups Use Both
This is why so many experienced lappers run:
- a portable blanket for flexibility and recovery
- roof solar for consistency
Common Solar Mistakes We See On The Road
- Oversizing solar but undersizing batteries
- Thinking solar will fix poor power habits
- Parking in full shade and blaming the panels
- Dirty panels (this matters more than people think)
- Expecting air con to “just work” off-grid
- Buying gear before understanding daily usage
- Using one cloudy day as the “benchmark”
- Forgetting winter sun angle and shorter days
FAQs
How Much Solar Do I Need To Stay Off-Grid On A Big Lap?
The average modern Big Lap setups sit around 800W to 1200W+, usually roof + portable. The right number depends on your battery size, how long you stay put, and what you run daily.
Is Roof Solar Enough On Its Own?
For light users who move often, yes. For longer off-grid stays or shaded camps, roof solar alone is usually not enough.
Does Solar Work In Winter?
Yes, but output is lower due to sun angle and shorter days. This is where portable solar and larger battery capacity really help.
Can Solar Run An Air Conditioner?
Not directly. Solar recharges batteries, and batteries run the air con. Air con off-grid requires big battery capacity, lots of solar, and realistic usage.
Do I Still Need A Generator?
Some lappers carry one as backup, especially with air con or long stays. Others build big enough to avoid one. It comes down to your comfort level with risk, weather, and how remote you camp.
Final Thoughts
Getting solar right for a Big Lap isn’t about chasing the biggest number on paper.
It’s about:
- understanding how you actually camp
- being honest about power-hungry appliances
- matching solar to battery capacity
- building flexibility for shade, weather, and seasons
Once you get that, solar stops being overwhelming and starts being a simple, practical plan.
If you want a shortcut: I’ve got a step-by-step way to choose a setup based on your travel style (not someone else’s rig ). That’s exactly the kind of planning I teach inside my Big Lap resources, and it’s also where TrackMate helps you map the style of trip you’re actually building.
With years of experience travelling Australia in a caravan, I’m passionate about helping others embark on their own unforgettable adventures. From off-grid camping tips to expert advice on planning the ultimate big lap of Australia, I share stories, practical hacks, and inspiration to make your journey stress-free and exciting. Whether you’re a seasoned traveller or just starting out, join me as I explore the beauty of Australia, one road at a time!
