How Much Does a Rooftop Tent Reduce EV Range? What Australian Drivers Need to Know

Planning a camping road trip in an EV is entirely achievable in Australia, but strapping a rooftop tent to your roof before a long drive will meaningfully reduce your range. Understanding why - and by how much - lets you plan stops accurately instead of guessing and hoping.

The physics: why a rooftop tent hurts more than you might expect

Aerodynamic drag is the dominant energy cost at highway speeds for any vehicle, but it matters far more for EVs than for petrol cars. A petrol engine wastes so much energy as heat that an extra 20% drag penalty is relatively small noise against its broader inefficiency. An EV, which converts around 90% of its stored energy into motion, has less waste to hide behind - every additional drag force translates almost directly into extra kilowatt-hours consumed per kilometre.

The drag force on a vehicle is described by:

Drag force = 0.5 × Cd × A × ρ × v²

Where Cd is the drag coefficient, A is the frontal area, ρ (rho) is air density, and v is velocity. The critical term is v² - velocity squared. Double your speed and drag force quadruples. This also means that adding a large, bluff object to the roof of an otherwise aerodynamic car compounds in effect as speed increases.

A rooftop tent is not aerodynamically designed. It is a box. Its contribution to Cd and frontal area is substantial. At 60km/h the penalty is modest. At 100km/h it is significant. At 110km/h it worsens further still.

Actual numbers: roof rack vs. rooftop tent

The range impact breaks down roughly as follows at Australian highway speeds:

• Bare roof rack, no load: +5–10% energy consumption at 100km/h
• Rooftop tent, closed and latched: +15–25% energy consumption at 100km/h
• Rooftop tent, open and deployed: Not applicable - you are not driving with it open

The variance within each range reflects differences in tent design (some are more aerodynamic than others), driving speed, headwinds, and total vehicle load. A larger, taller hard-shell tent will sit at the worse end of that range; a compact soft-shell tent may come in closer to the lower end.

What this means for the Tesla Model Y

The Tesla Model Y Long Range AWD is one of the most common EVs used for Australian camping trips. Tesla rates it at approximately 533km of WLTP range. Real-world highway range at a steady 100km/h - accounting for climate control and realistic conditions - sits closer to 490–510km on a full charge.

Add a rooftop tent and drive at 100km/h:

• Realistic range with tent: approximately 375–425km per charge
• At 80–90km/h with tent: range improves to roughly 430–470km, because the drag penalty shrinks substantially at lower speeds

For context, the drive from Sydney to Melbourne via the Hume Highway is approximately 880km. Without a tent, a Model Y covers that comfortably in two charging stops. With a tent at 100km/h, plan for three stops and allow more buffer between them.

EVs with larger batteries handle the penalty better

A 15–25% range penalty is fixed as a percentage, but its impact in real kilometres depends entirely on battery size. A larger battery starts with more room to absorb the loss.

Tesla Model Y Long Range (75kWh usable): ~500km real-world highway range drops to ~375–425km with a tent - workable with planning on most Australian highway routes.

Kia EV9 AWD (99.8kWh usable): Real-world highway range of approximately 480–510km drops to roughly 360–435km with a tent. The larger battery and available 240kW DC charging make the EV9 one of the more capable camping EVs currently available in Australia. The additional buffer genuinely matters on legs where chargers are spaced 200km+ apart.

Smaller-battery EVs - anything in the 55–65kWh range - will feel the tent penalty more acutely on longer legs. A 20% range reduction on a car with 300km of real-world highway range leaves you with 240km of practical distance, which is tight on routes where the next Chargefox or Supercharger is 200km away.

The Australian context: distances matter here more than anywhere

Australia’s charging infrastructure has expanded considerably - Chargefox operates around 950 sites nationally as of 2025, and Tesla Superchargers cover most major highway corridors. But the spacing between chargers on regional and remote routes is often 150–250km, and some outback legs stretch further. A 20% range reduction can turn a comfortable charge stop into a stressful low-battery arrival if you have not planned for it.

Key routes and what the tent penalty actually means in practice:

• Hume Highway (Sydney–Melbourne): Well-serviced with Chargefox and Supercharger stops; manageable with an extra stop built in
• Pacific Highway (Sydney–Brisbane): Good coverage; monitor consumption on hilly sections around the NSW–Queensland border
• Stuart Highway (Adelaide–Darwin): Charger gaps exceeding 200km in places - tent-equipped EVs should plan charging stops conservatively and carry a clear contingency
• Regional Western Australia: Charging infrastructure is thinner and distances are greater; conservative planning is essential and a pre-trip route check in ABRP is non-negotiable

The honest assessment: EV camping trips are viable on most Australian highway corridors right now. They require more pre-trip planning than in a petrol vehicle, and that planning gap widens when you have a rooftop tent fitted. The solution is not to leave the tent at home - it is to plan with accurate numbers rather than the figures printed in the brochure.

Mitigation strategies

Drive slower. This is the single most effective intervention available. Dropping from 110km/h to 90km/h reduces drag force by around 33%, which translates to a real and measurable range gain. On Australian highways where the limit is typically 110km/h, sitting at 90km/h is legal on most roads and practical on quieter outback routes. The time cost is real; the range gain is real - weigh them against each other based on your specific leg.

Remove the tent between long highway legs. If your trip involves a 300km+ highway run between campsites, removing the tent at departure and reinstalling it on arrival is worth the 15–20 minutes of effort. Even a compact rooftop tent adds 5–10% to energy consumption as a bare rack once it is off - and the tent itself adds far more. Recovering 80–100km of effective range on a demanding leg is a meaningful improvement.

Use ABRP with a 20% consumption penalty. A Better Route Planner (ABRP) is free, widely used in the Australian EV community, and more accurate than in-car navigation for multi-stop route planning. In your vehicle settings, apply a 20% reference consumption increase to account for the tent. ABRP will then plan charging stops that leave you arriving with a genuine buffer rather than the minimum. This single setting change eliminates most of the anxiety from a tent-equipped highway trip.

Charge to 90% on demanding legs. On days where the itinerary is tight, charging to 90% at a stop - rather than the more typical 80% endpoint - provides additional buffer without meaningfully degrading battery health over a short trip. The last 10% charges more slowly at DC fast chargers, so weigh the time cost against the margin you actually need.

Watch real consumption, not estimated range. Tesla’s estimated range display - and most other EV displays - is calculated from recent driving history and can be optimistic when conditions change. Watch the kWh/100km figure on the energy screen instead. A normal highway figure for a Model Y is around 18–20kWh/100km. If you are seeing 24–28kWh/100km with the tent fitted and a headwind, your consumption has increased significantly and your stop plan should adjust accordingly.

Summary

A rooftop tent will reduce your EV range by roughly 15–25% at 100km/h. On a Tesla Model Y, that means planning for around 375–425km between charges instead of 490–510km. Larger-battery vehicles like the Kia EV9 give you more absolute buffer, which matters most on the longer legs between regional Australian chargers. The mitigation is practical: drive at 80–90km/h where possible, use ABRP with a 20% penalty setting, and plan charging stops based on your reduced range - not the figure on the sticker.

EV camping in Australia is genuinely viable. The rooftop tent is not a free addition to your setup, but it is an entirely manageable one if you go in with accurate numbers. Use our EV range calculator to estimate real-world range at highway speeds for your specific car before you plan a camping route. Browse all AWD and long-range models suitable for camping on our electric vehicles hub. If you’re choosing a vehicle for family camping trips, our best family SUV EV guide covers the most practical options for Australian road trips.