The 2017 Simpson Desert Solar Crossing: What Happened and What's Changed

In September 2017, a modified Suzuki SJ413 Sierra crossed the Simpson Desert on nothing but sunshine. The vehicle, prepared by the Baringa Solar team and led by Chris Selwood, completed the approximately 500 km crossing from Birdsville to Mt Dare in 4 days, 21 hours - fast enough for a Guinness World Record for the fastest solar-powered crossing of a desert.

Most coverage of this achievement at the time focused on the novelty of it. A small, quirky off-roader, running on panels and batteries, crossing one of Australia’s most serious desert environments. The story has circulated in Australian motoring and adventure communities since. What has received less attention is what the feat actually demonstrated from an engineering perspective, and how much the technology involved has changed in the eight years since.

What the Vehicle Actually Was

The Baringa Solar team’s vehicle was not a commercial EV with a roof rack full of solar panels. It was a purpose-built conversion.

The base was a Suzuki SJ413 Sierra - an early 1990s compact 4WD with a solid reputation for basic mechanical reliability and relatively low kerb weight (approximately 900 kg). The team removed the petrol engine and drivetrain, replaced it with an electric motor and controller, added a lithium battery pack for energy storage, and mounted a solar array to the vehicle and a deployable extension panel system.

The solar array was relatively modest by current standards - the exact wattage reported across different sources varies, but the system was designed around available panel efficiency of the time, roughly 17–18% for quality monocrystalline cells in 2017. The key innovation was the solar management system, which optimised charging during the day and managed draw during driving to maximise range on available solar energy.

The vehicle was lightweight by any expedition standard, which helped significantly with energy demand. A bare-bones 900 kg EV conversion on soft sand uses considerably less energy per kilometre than a fully equipped 2,500 kg expedition 4WD.

The Simpson as a Test Environment

The Simpson Desert is the right proving ground for this kind of attempt. It’s not the hardest terrain in Australia - the corrugations of the Gibb River Road, the sharp rocky surfaces of parts of the Flinders Ranges, and the bottomless mud of the Cape York wet season are all more mechanically demanding. But the Simpson offers an almost perfectly controlled variable: consistent soft sand, reliable sunshine, a defined route with waypoints, and enough remoteness to be genuinely challenging without the total communication blackout of the most isolated parts of the continent.

The approximately 1,200 dunes of the French Line provide repeated climbs and descents, which are interesting for energy management: climbing costs energy, descending on a converted EV can regenerate some of it, and the net balance informs solar sizing. At the pace the Baringa team travelled - approximately 100 km per day, consistent with the 4d21h overall time - the daily energy demand from driving was manageable alongside solar input.

September is also close to optimal for this kind of attempt. Temperatures are rising but not yet at the 45–50°C summer extremes, and solar irradiance is strong without the panel temperature penalties that peak summer imposes.

Why the Achievement Matters More Than It Looks

The 2017 crossing was not a stunt. It was a proof of concept for a specific question: can a small, purpose-built solar electric vehicle complete a genuine desert crossing on solar energy alone, in a reasonable timeframe, without external energy support?

The answer was yes - with the right vehicle weight, the right solar capacity for the energy demand, and the right desert (the Simpson, with its consistent sunshine and defined route, is close to the ideal case).

The demonstration is meaningful because it established lower bounds on what is required: approximately 100 km per day of desert travel, a vehicle in the 900–1,200 kg range, solar sufficient to replenish daily demand. Extrapolating to heavier vehicles and longer, harder routes like the Canning Stock Route gives you a useful (if rough) scaling factor.

What Has Changed Since 2017

The eight years since the Simpson crossing have produced substantial improvements in every component relevant to solar EV expeditions.

Solar panel efficiency. The most significant change. Premium monocrystalline silicon panels in 2017 achieved 17–19% module efficiency. By 2026, the leading commercial monocrystalline panels - from Sunpower, LONGi, and Jinko - reach 22–24% module efficiency. That is a 25–40% improvement in energy output per unit area. A panel that produced 350W in 2017 at the same physical size now produces 430–440W.

For portable, vehicle-mounted solar, the efficiency improvement per unit area directly reduces the number of panels (and therefore weight and volume) needed to reach a target power output. A 10 kW array that required approximately 30 panels in 2017 can now be built from 22–24 panels of equivalent size.

Flexible panel technology. The most relevant improvement for mobile applications. In 2017, flexible solar panels used thin-film cell technology (CIGS or CdTe) with efficiencies of 10–14%. They were lightweight but required large areas for meaningful output.

By 2026, flexible monocrystalline panels using back-contact cell technology - the same high-efficiency cell architecture as premium rigid panels - achieve 18–22% efficiency in flexible format. Products like the Solbian SP series and SunPower Flexible panels use this technology. The weight reduction is dramatic: a Solbian SP series flexible panel weighs approximately 2.2 kg/m². A 440W panel from this range weighs around 3.5–4 kg versus 20–28 kg for a rigid framed equivalent. For a 10 kW array, that difference is 80 kg versus 440–560 kg.

Battery energy density. Lithium iron phosphate (LFP) chemistry, now the dominant choice for EV battery packs in the sub-$100k vehicle market, has improved in energy density since 2017. More relevantly, battery management systems have become significantly more sophisticated at managing temperature, charge rate, and depth of discharge to protect cycle life in demanding conditions. An EV battery pack doing daily deep cycling in 40°C ambient heat in 2026 manages this far better than equivalent hardware in 2017.

Motor controllers and drivetrain electronics. Inverter efficiency in 2017 production EVs was typically 92–95%. Modern EV drivetrain electronics routinely achieve 96–98% efficiency. For a vehicle running close to its energy budget, this improvement is meaningful.

MPPT controllers. Maximum Power Point Tracking controllers - essential for extracting maximum energy from panels operating at variable irradiance - have improved in both efficiency and input voltage range. High-quality MPPT controllers now operate at 97–99% efficiency versus 93–96% for typical 2017 units. For a 10 kW array operating for 6 hours per day, a 3% efficiency improvement recovers approximately 1.8 kWh daily.

What a 2026 Attempt Would Look Like

Applying 2026 technology to the same challenge - a Simpson Desert crossing in a solar electric vehicle - the numbers change substantially.

A purpose-built lightweight vehicle (around 1,000–1,200 kg) with 40–50 kWh of battery storage and 8 kW of current flexible panel capacity could realistically generate sufficient energy to complete 100 km per day across the Simpson Desert in reasonable conditions. The panel array, using Solbian-class flexible panels, would weigh approximately 65–80 kg - significant, but not expedition-breaking for a lightweight base vehicle.

For a full-size expedition EV - the scenario relevant to an attempt on the Canning Stock Route - the vehicle weight is 2,000–2,500 kg, energy consumption is 50–65 kWh per 100 km of demanding track, and battery capacity needs to be 60–80 kWh minimum to provide any meaningful single-day range. The panel array needed to replenish 60 kWh per day (accounting for 70% yield losses) at current panel efficiency is approximately 12–14 kW rated capacity. At Solbian weight figures, that’s 95–110 kg of panels - at the upper end of manageable for a large 4WD expedition vehicle, but achievable.

The 2017 crossing proved it is possible in principle. The 2026 technology means it is more achievable per kilogram of panel weight than ever before. The challenge that remains is purely mechanical and logistical: stowing, deploying, and managing 12+ kW of panels on a vehicle that also needs to traverse serious desert terrain.

That engineering problem does not yet have a neat commercial solution. But people who solve hard problems in creative ways are already working on it, and the Reddit discussions that keep circulating around questions like “could you do the Canning in an EV with enough solar” are the public surface of genuine engineering curiosity that tends to produce answers over time.