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Australian concept Electric Vehicle runs on its own solar panels by Ross Tester Imagine driving an electric vehicle which NEVER requires plugging in – all its power for normal operation can come from roof and bonnet-mounted solar panels. If a Melbourne start-up turns its “Immortus” concept into a production vehicle, that’s exactly what will happen. I f you’ve ever scanned the comments section on an electric car or bike article, you’ll be familiar with this complaint: “that’s not green, it’s just a coal-powered vehicle.” The detractors are, of course, referring to the fact that an EV’s power had to be generated somewhere, for example a coal-fired power station. They are completely ignoring the fact that many EV owners generate their own power (solar) or even pay extra to have “green” power (hydro, wind etc). Well, they can’t denigrate the Immortus. While still a “concept” EV car (ie, none have actually been built yet, let alone sold!), it has been designed to generate either 100%, or the vast majority (depending how it is driven), of its own power through some seven square metres of solar photovoltaic paneling mounted on its roof and bonnet. You can charge its battery off the mains if you have to but if conditions are sunny, the inbuilt solar panels alone will let you drive at more than 60km/h for an unlimited distance. Solar racing heritage The Immortus technology is based on solar racecars, which are powered solely by what they can generate from their solar cells as they drive along (ie, no plug-in power or even generators allowed). The project was originally founded by Australia’s Aurora Solar Car Team, which has competed in a bunch of solar race events across the world. Hence the light weight and the shape of the Immortus, which combines maximal sun exposure with extreme aerodynamics, including covered wheels. 30  Silicon Chip Unlike the solar racers, though, the two-seater Immortus is designed to approach practicality on the road, with a 0-100km/h time that will be less than seven seconds and a top speed over 150km/h. It also has a modest luggage capacity for daily driving. Melbourne-based EVX Ventures, creators of the Immortus, even list fun as a priority, saying it should handle like a well-balanced sports car. Squeezing unlimited range from solar energy Where the Tesla Model S has a massive 85kWh battery pack, the self-charging system on the Immortus uses only a 10kWh lithiumiron-phosphate battery. The car uses twin DC motors mounted on the uprights leading to each rear wheel hub, each with a peak output of 20kW, for a total peak output of 40kW (53.6 hp). While 40kW doesn’t sound like much, the entire car has been designed to make the most of its power. A feather-light weight of around 550 kg (1,212 lb) gives the Immortus a power-to-weight ratio and acceleration time similar to a Mazda MX5 (aka Miata) and the weight distribution is designed to offer similarly sporty handling characteristics. The Mazda will out-corner it though, because the Immortus won’t use regular road tyres. It will use tyres specifically designed for solar racers; very thin wheels with low-friction tyres that prioritise low rolling resistance over grip. These aren’t the most attractive wheels but then they’re hidden away behind the aerodynamic wheel arch covers anyway. Thanks to exceptionally low weight, low-drag aerodynamics, EVX expects the car’s small 10kWh battery pack to be good for just under 400km of range even at night, when there’s no solar assistance topsiliconchip.com.au ping it up. When the sun is out and the road is clear, that range goes up, effectively to infinity if you stay around 60km/h. Upping the pace to 85km/h the range drops to about 550km. Distributed manufacturing – every car a custom Ease of construction is key for the Immortus team, because they don’t plan to mass-produce the car, or even to build it in-house. “We’re not trying to be a Tesla,” says Barry Nguyen, CEO and co-founder of EVX Ventures. “Tesla is a mass manufacturer of cars, we’re designers of boutique custom electric cars and aftermarket products. There are regulations in the US and Australia that allow for individually constructed vehicles. Essentially what that means is that if you contract a custom car builder with the designs and components, you can build a road-legal car without the crash testing and the 5-10 million dollars you’d have to raise to do that. We plan to sell those cars in low volume.” Thus, the Immortus has been designed to be exceptionally simple to assemble. Abandoning early concepts that used a carbon-fibre monocoque frame with two large tubs, the most recent design features an ultra-lightweight space frame using off-the-shelf carbon fibre tubing, with 3D-printed nodes to connect the tubes. The frame of the car is effectively like a big Meccano set. “This simplifies the manufacturing process, as well as reducing transport costs,” says technical lead Clint Steele. “The plan is to have these cars assembled by custom car builders close to wherever the customer is. The custom shops can source their own carbon fibre tubing and we can either send over the 3D-printed node parts or send over the designs so they can print them locally.” Got a lazy half-million? EVX doesn’t expect to sell more than 100 of the Immortus. At an estimated AU$500,000 (approx. US$370,000) depending on spec, it’s a boutique, high priced technology platform that will only appeal to extremely wealthy early adopters. But the ideas developed through the Immortus project are filtering out into a range of other projects that are much more consumer focused. EVX is looking to raise about US$1.5 million to get the Immortus production ready, and will be taking a scaled-down, remote control version of the Immortus to this month’s (October) SEMA exhibition in Las Vegas. EVX is still trying to decide whether to remain in Melbourne or to move to California. “Melbourne is home,” they say, “but California has a lot more high-worth early-adopters, the kind of people who might take a half-million chance on an unproven solar car.” Either way, early as it is, the Immortus, along with the Stella Lux prototype from the Netherlands, paves the way for a new category of vehicle, one that’s all but energy independent. An electric car in which you rarely, if ever, have to think about where the next charge point is; a high-end, high tech sportscar you won’t want to keep in your garage, because it can’t get any sun in there. And as battery technology and photovoltaic efficiency continue to improve, these kinds of cars could become a lot more viable. SC (Illustration and some text credit: EVX Ventures, Melbourne) It’s not just the solar panels which make this car unique: even the shock absorbers are designed to produce power! siliconchip.com.au Think this is all “Pie-in-the-sky” stuff? Pictured above is the “Sunswift V (or eVe)”, the University of New South Wales award-winning entrant in the World Solar Challenge (WSC) race from Adelaide (SA) to Darwin (NT). That this vehicle holds a number of world records, including the Guinness World Record for the fastest solarpowered vehicle is significant enough. However for this story, what is even more significant is that this vehicle is the first in Australia – and one of very few in the world – which is road legal; that is, it passes the strict Australian Design Rules (ADRs) which means it can be registered and used on Australian roads. World Solar Challenge entrants have all run under special provisions, meaning vehicles incapable of “normal” operation were permitted to run the race. In fact, earlier WSC racers have been anything but road legal; more somewhat flimsy and unstable mobile platforms on which solar cells are mounted! (See the photo of the 2013 Adventure class winner, the Aurora Evolution, on which the Immortus technology is loosely based). Drivers of the earlier racers reported the dread of seeing a road train approaching – in fact, there were at least a few accidents as the buffeting of very fast-moving road trains and even caravans took their toll on the lightweight race cars. The wing-shape didn’t help at all! Even so, the times achieved by the solar-powered racers, moving from the first rays of sunlight in the morning, to just before dusk (rules dictated when the cars could move) were quite impressive: the Aurora Evolution achieved first place in 38 hours and 39 minutes driving time – some 3022km – at an average speed of 77.5km/h. October 2015  31