Automotive

Solar-powered car claims new EV speed record over 1,000 km

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The Sunswift 7 on the track
Richard Freeman/UNSW
The Sunswift team tend to the vehicle
Richard Freeman/UNSW
The Sunswift 7 will take part in the Bridgestone World Solar Challenge in 2023
Richard Freeman/UNSW
The Sunswift 7 on the track
Richard Freeman/UNSW
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An engineering team in Australia working at the cutting edge of electric vehicle design have laid claim to a new world record. The University of New South Wales Sydney’s (UNSW) Sunswift 7 solar-powered car recently took to a testing circuit where it covered 1,000 km (621 miles) on a single charge in less than 12 hours, an achievement that pushes the envelope when it comes to aerodynamics and efficiency.

Engineers at UNSW have been producing solar-powered cars since 1996, and in recent years we’ve seen them set a string of speed records for electric vehicle performance. The Sunswift 7 is UNSW’s latest solar-powered car and weighs just 500 kg (1,100 lb), or around a quarter the weight of a Tesla.

To achieve this light weight, the engineers had to forego air conditioning systems, ABS brakes, airbags, windscreen wipers and other features you’d expect to find on a street-legal production car, instead focusing on aerodynamic efficiency and rolling resistance. Where a Tesla Model S has a drag coefficient of 0.208, the Sunswift 7 has drag coefficient of just 0.095.

The Sunswift 7 will take part in the Bridgestone World Solar Challenge in 2023
Richard Freeman/UNSW

The team spent two years piecing together the Sunswift 7 with a Guinness World Record in mind, hoping to demonstrate the fastest solar electric car over 1,000 km. This record attempt recently took place at the Highway Circuit test track at the Australian Automotive Research Centre, with the Sunswift 7 completing 240 laps on a single charge.

It wasn’t all smooth sailing, however, with the team needing to overcome a battery-management issue and a punctured tire to complete the journey. Driver changes also took place every few hours, with the vehicle completing the 1,000-km trip in 11 hours, 53 minutes and 32 seconds, at an average of almost 85 km/h (52 mph).

This unofficially positions the Sunswift 7 as the fastest electric vehicle over 1,000 km on a single charge, though the team is awaiting official confirmation on timing and car telemetry data to obtain its Guinness World Record Certificate.

“During this record, the energy consumption was just 3.8 kWh/100 km (62 miles), whereas even the most efficient EVs on the road today only achieve a rating of 15 kWh/100km and the average is around 20 kWh/100km,” said Professor Richard Hopkins, Team Principal. “Sunswift 7 isn’t a production car of the future, since we’ve compromised on comfort and the cost is prohibitive. But we have shown that if you want to make cars more efficient, more sustainable, more environmentally friendly, then it is possible.”

The Sunswift 7 will also take part in the Bridgestone World Solar Challenge in 2023.

Source: University of New South Wales

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13 comments
Mutt-online
A good result - and I appreciate the sentiment to move from fossil fuels - but at that sort of efficiency the car would only consume 0.33 l/100km of gasoline so I have to then ask if the overall lifetime CO2 footprint for such a fossil fueled car wouldn't be a lot lot less...considering the energy efforts required to make battery, solar cells etc.
Mutt-online
Apologies - about 1l/100km in my earlier post - have to consider energy to road efficiency losses..but still the same question :-)
vince
The fallacy of EV's is that the depend on unusually high efficiency aerodynamics. So when you interfere with that efficiency by adding a bike rack with 4 bikes you destroy that efficiency and the range goes all to pot. Worse, if you use the vehicle to tow the tires on the towing trailer are not high efficiency EV tires but tires rated for load and rolling resistance goes up by an order of magnitude. So hauling a couple of bikes which many people do and towing a small popup camper trailer means the range can drop by a factor of 5 or more. That makes them unusable for most folks.
usugo
indeed, in summer at 90km/h
- ioniq 28kWh, 11kWh/100km
- M3 SR+ LFP, 12kWh/100km
- ID3 58kWh, 13.5kWh/100km
- I4 M50, 15.5kWh/100km
usugo
@Mutt-online
when will ever an ICE car consume 1L/100km?
In summer, at 90km/h a number of EV sedans can already achieve real world consumption equivalent to 1.5L/100km.
A Volvo report compared the life cycle CO2 emission of its XC40petrol vs XC40 recharge (a rather inefficient EV). Parity point is achieved after 50k km when EV is charged with electricity from renewables, and taking for good (confident it is not) official WellToWheel CO2 emissions for gasoline.
Bottom line, your question is mut ... moot
Rustgecko
I wonder what milage it'd achieve in Old South Wales instead of the new one?
kwalispecial
@Vince: Those are fair observations about factors that reduce efficiency, but when I look around, I would bet 1/20 of the cars on the road have bikes (or boats) on the roof or a trailer. More during vacation time, but probably not more than 1/10 at peak. If you figure most driving happens on the daily commute (when very few are pulling trailers or hauling bikes) you are going to benefit from the efficiency for the majority of your trips. If you lose some efficiency occasionally, that's still small potatoes.
Username
@vince Most folks, by a large margin, do not tow trailers or carry bicycles. Any picture of any road on any given day will show this.
1stClassOPP
I’m not sure what the comparative numbers mean, as in Mutt-online, but perhaps it means if you hav an ICE powered vehicle you achieve the same efficiency? If you used the same drag coefficient, you would not need much of an ICE engine, horsepower wise to move that vehicle, so fuel wise would be minimal, and perhaps the total energy used to produce the ICE powered vehicle more efficient than the solar powered vehicle.
EVUK
Sunswift developers UNSW always have trite, worn-out excuses at the ready to "explain" why their solar vehicles couldn't be mass-produced. In this article we're given the old "prohibitively expensive" excuse. Why?! This vehicle is all about minimalism. So what exactly is "prohibitively expensive"? A university produces these ostensibly "prohibitively expensive" Sunswift EV iterations which are never mass-produced for consumers. UNSW needs to be far more precise with their excuses. Which components, materials etc would prevent the price from plummeting if a defiantly disruptive manufacturer were to commit to producing, say, 50,000 Sunswifts a year? Half of them in China?
Paul G