How many cars does it take to win a solar race?

How many cars does it take to win the Bridgestone World Solar Challenge? Surely, just one?

Of course, one car – the solar car – is the focal point, but the eventual winner will use at least two, and potentially up to a dozen vehicles to complete the event, which gets underway on Sunday 22 October.

At the heart will be, of course, the competition vehicle competing in one of the two categories as part of the event.

That solar car will, however, be surrounded by up to 10 other vehicles travelling as part of the race team – each playing a vital role in the success – or failure – of their 3020km quest.

Sadly, with slow uptake of conventional electric vehicles and associated infrastructure in Australia, most of these cars are petrol-powered, with the solar racer the only part of the convoy running off the sun’s energy.

Still, amid the competitive element of solar racing, the need for safety of team members and the logistical exercise of keeping teams of at least 20 people fed and watered in the heat of the Australian outback, these small fleets are necessary to success.

A ute loaded with weather monitoring equipment.
Weather monitoring is a key part of the strategy for many teams. Credit: Matthew Ward Agius.

The weather car

When the race resumes at 8:00am each morning, many teams will already have a car that has been running for at least 45 minutes. Racing ahead of the pack, these cars make weather observations and upload data to the cloud so this can be studied by strategists near the solar car. Not every team will operate a weather car as part of the event.

A silver suv is kitted out with weather monitoring equipment.
Credit: Matthew Ward Agius/Cosmos.

Prep vehicles

Challenger teams may run a preparatory vehicle to set up each of the nine control stops. During the event, cars will stop over at nine checkpoint towns along the route. Here, they engage a 30-minute window allowing for a driver change and small adjustments to the solar car. Prep teams effectively establish ‘runways’ to guide the vehicle into a predetermined stop position, and assist the driver to exit the vehicle and sign on to the control stop. Think of it as a runway landing with the intensity of a Formula One pit stop. Most teams will run three drivers on rotation between control stops, allowing time to recover and rehydrate. They need it, with cabin temperatures exceeding 50°C in the Northern Territory, a full day to recover is welcome, even with some cooling in the cockpit.

A white 4wd is ready to set out and monitor the conditions ahead of the solar car.
The lead car plays a key role in keeping the solar car driver safe. Credit: Matthew Ward Agius/Cosmos.

The lead (or scout) car

Sits in front of the solar car, effectively screening for forward road hazards, which include massive road trains approaching in the other direction, cattle and wildlife, potholes and, as occurred on day 1 and 2, bushfires. Giving forward warning to the solar car driver enables them to position their car to safely navigate the event. Scout cars also need to drive about 500m in front of the solar racer – they aren’t allowed to punch a hole in the air and allow the competition vehicle to gain a slipstream advantage.

A solar car
Many of the solar cars are joined by a fleet of support vehicles. Credit: Matthew Ward Agius/Cosmos

The solar car

The competition vehicle. Whether a single-occupant Challenger car or multi-occupant Cruiser car, this vehicle is being closely studied by all cars in the team convoy surrounding it. The driver is instructed by team strategists who primarily advise the precise operation speed. The driver is also relayed forward road information by the lead car on vehicle positioning and upcoming road hazards.

A white van with communications o the roof. Company logos adorn the side of the van.
Real-time data is used to refine the team’s strategy. Credit: Matthew Ward Agius/Cosmos.

The chase (or strategy) car

The brains of the operation sit here. Team leadership and race strategists pore over all the data being uploaded by the solar car and other support vehicles to adjust the speed and strategy of the race.

Telemetry from the solar car is beamed to the strategy team, which analyses and models the data in real time. Primarily, this includes the amount of energy being converted by the solar array, the rate of battery discharge when in use, and the time to charge the battery throughout the race.

A silver suv is packed to the brim with kit, ready to swoop in and make any adjustments needed to the race car.
The crew car is at hand should anything go wrong with the solar vehicle. Credit: Matthew Ward Agius/Cosmos.

The crew

Think of this like the pit crew of a typical motor racing operation. In here, team personnel are waiting ready to go to make fast adjustments to the car if something goes wrong. Ideally, this lot get to sleep through the whole race.

A white 4wd carries the media team.
The media vehicle is there to capture all the action. Credit: Matthew Ward Agius.

The media and other support cars

For the best-resourced teams, these cars will be full of team media personnel, camera crews and social media staff waiting to get the best shots of the challenge as it unfolds. Largely, their job is to foster storytelling of the expedition for sponsors and media agencies back home. So popular is solar racing in the Netherlands and Belgium (probably because these countries do particularly well at it) that a victory by one of these teams will get widespread coverage in their home nation.

A semi-trailer driving through australia's outback.
Trucks and trailers are used to transport to the solar car and all the supporting crew and equipment. Credit: Matthew Ward Agius/Cosmos.

The trucks and trailers

All the equipment has to go somewhere. Whether it’s a massive shipping container or a small trailer, teams need to be able to have enough towing infrastructure to carry their solar car, camping equipment and more.

A 4wd is parked off to the left of a group of cars and truck belonging to a competitor team.
I spy with my little eye. The top teams aren’t too concerned about their spy cars being spotted. Credit: Matthew Ward Agius.

Spy car

A good spy should, generally, be hard to spot, but in solar challenges the top teams are a little more brazen. It’s hard to get an exact description of what these not-so-covert secret agents are doing (Cosmos saw the Innoptus team’s spy car smile and wave at their close competitors from Twente, for instance). But what we do know is their job is to scout around for the competition and report back to their strategists what the opposition are up to, where they are on the road, coordinates for where they finish each day, the nature of their nightly camps, even the final position of their car and how much light their cells can be expected to receive before sunset. Solar and battery efficiency numbers are closely guarded secrets, so any small piece of information these observers can obtain about the competition is useful.

Subscribe to ultramarine from riaus

Cosmos is the Scientific Media Partner of the 2023 Bridgestone World Solar Challenge Follow our coverage.

Please login to favourite this article.