Aussie teams build showroom-worthy solar cars

Three Australian universities are putting pedal to the metal with the construction of passenger cars powered primarily by the sun.

University teams from UNSW, Deakin and Flinders will compete in the upcoming Bridgestone World Solar Challenge in a unique category that demands production-style vehicles capable of transporting multiple passengers from Darwin to Adelaide.

The journey of more than 3000km through Australia’s Red Centre will be led by cars in the “Challenger” class – small, bullet-like single-occupant vehicles designed to operate as quickly and efficiently as possible.

Trailing behind them in the “Cruiser” division will be a dozen, far larger vehicles that look more like cars one might see in a main road showroom.

These vehicles are four-wheeled, carrying at least one passenger, and will complete the challenge in three 1,200km legs. The category isn’t about being the first over the line, it seeks instead to trial innovations in technology, energy consumption and practicality. These are required to be both efficient and practical, as opposed to their Challenger counterparts that simply seek to reach Adelaide before all others.

Being first to Adelaide doesn’t necessarily guarantee class victory for Cruiser competitors either: rather than time being the sole determinant of victory, teams are given a final score based on distance travelled, on-road penalties, external energy use and practicality – a subjective measure of whether the car has ‘showroom’ appeal.

Record-breakers looking for more success

Of Australia’s competitors, the Sunswift Racing team is the most experienced. Hailing from UNSW Sydney, it will also be the most experienced in the 2023 Cruiser field. Its sleek silver machine looks like it could be made by a famed automaker like Audi (and unsurprisingly the German marque is one of its major backers). Sunswift is also spearheaded by former Red Bull F1 team head of operations, Professor Richard Hopkins, who mentors his students as if they were personnel working in top-flight motorsport.

The team’s car – Sunswift 7 – recently set a Guinness World Record for the fastest 1,000km achieved by an electric car on a single charge, achieving the feat in just under 12 hours at an average speed of 85km/h.

Events like that are part of a ‘roadmap’ set by Sunswift following the pandemic to transition, as many leading solar teams now have, from being simply a university opportunity into an increasingly standalone entity. The 2023 Cruiser challenge will be the first chance to pitch Sunswift 7 against teams from around the world.

“The car would’ve been ready to race in ’21, no problem,” Hopkins says.

He’s referring to the COVID-cancelled 2021 edition. Sunswift 7 was intended to debut that year, but with new regulations issued for the 2023 event, only the shell has been retained.

“Externally, the car looks the same, apart from it being a different colour. Internally, it’s completely changed.”

“The last 18 months have been a development fest. You do 1,000km for a Guinness World Record, and as much as we achieved it and go the record, you end up with a whole load of improvement that you can find.”

The data of that 1,000km world record tilt will flow through to tiny adjustments to extract as much potential out of the car for the challenge – a practice that is, as Hopkins says, “the DNA of motorsport”.

“[Now] we could quite easily beat our own world record by ‘X’, because of the improvements we’ve made. It’s been a constant journey.”

Sunswift’s data acquisition over the past 12 months will be vital in its quest for class victory in October. As Hopkins acknowledges, many of their competitors will likely be brand-new vehicles.

Newcomers out of Australia’s auto heartland

One of those will be a debutant from Deakin University. 

The new Ascend Solar Racing team is a partnership between Deakin and Spanish renewable energy infrastructure giant Acciona. It is based at the university’s Geelong campus – one of Australia’s old automotive heartlands, which was Ford’s Australian manufacturing hub from 1925 to 2016.

Ascend’s new car, complete with a red and silver livery, is supported by leaders from Deakin’s School of Engineering. It looks Bond-esque, almost a submarine on wheels.

Unlike Sunswift 7, which is living its second life under a new set of regulations, Ascend’s car is a first: designed specifically for the 2023 event without the benefit of previous competition to guide its development. But that’s not necessarily a bad thing – it means they’re starting with a clean slate.

Among the pioneering initiatives is the team’s approach to automotive construction.

“We’ve 3D printed the whole body, and used multi-jet fusion technology,” says team manager Matt Jennings, a lecturer in mechanical engineering at Deakin.

That 3D printing – or additive manufacturing – has allowed the team to create complicated parts for the vehicle. Their Hewlett Packard printer essentially prints nylon powder which is melted into the desired component shape.

It forms part of Ascend’s ambition to produce a zero-waste vehicle. No moulds are required to shape components and bodywork through this method, and the use of eco-resins and rock-extracted basalt fibre (rather than carbon fibre) pushes the use of sustainable processes in manufacturing the vehicle.

“We feel we’re, as a school, at the forefront of design, prototyping and using 3D printing as a tool for rapid prototyping. We wanted to show that off in the car,” Jennings says. “[With 3D printing] there’s no waste, you only use the material you’re using.

“There are detriments. It’s probably a bit heavier than a nice thin carbon fibre panel. But we wanted to push the boundaries.”

Ascend is ambitiously hoping to complete the event entirely under its own power – a feat many new teams often struggle to achieve, and compete with fancied rivals like Sunswift.

“It’s going to be hard, if we get anywhere near them, that’s a huge success for us.”

FAST… and fun

Flinders University is one of the ‘home’ teams in this year’s event. It’s participated in several events, having started as an initiative of one of the engineering school’s lecturers and a team of students.

And it’s very much moulded around the ‘club’ based nature of participant teams – driven by the student body rather than the institution.

That somewhat puts the team – which is yet to finish a Cruiser challenge entirely under its own power – on the back foot to cashed-up rivals from Australia and abroad. It spurred the Flinders group to pursue less costly design changes, like improving management structures and fostering a more professional culture for its student workers.

And it’s taken a different approach to design. The team itself is dubbed FAST (for Flinders Automotive Solar Team) and the car’s boxy aesthetic is intended to turn heads as it zips by, while being one of the safest vehicles in the field.

It’s minimalist fibreglass and aluminium panel design is intended to make the car light. There are only five panels built around a steel roll cage, so repairs are easy. And as the team’s vice-president Jamie Jackson says, it’s probably going to be fun to drive.

“We find that a lot of cars, and a lot of car designs these days are very ‘samey’,” Jackson says.

“You take a bunch of cars from the same category and sit them next to each other, and while they do have their unique design choices, there’s not really much that’s interesting. So we got our design and wanted to do something interesting and controversial that stands out from everyone else doing the challenge.

“I think we have something you could daily drive and in terms of safety, we are much safer than every other car – I will hold myself to that – as far as I know there are only 2-3 other teams using a full steel chassis and rollcage.”

Vehicle scrutineering for the Bridgestone World Solar Challenge commences on October 16, before the on-road event starts on October 22.