Doug Rolfe meets team Sunswift as they embark on their record breaking race with the very sleek eVe.
In the chill and deep morning fog north of Anglesea, the University of New South Wales Sunswift team is preparing eVe for a big day. This amazing car is a sleek, black vehicle that has the look of a high end sports car, yet it uses only around 3HP at 100km/hr.
With the solar panels carefully taped over and sealed against light leakage, the arrays disconnected and the solar power controller removed from the car, it has become a pure battery electric vehicle for an attempt at the world record for the average speed over 500km for a vehicle under 500kg. The previous record was 73km/hr set in 1988 by the GM Sunracer. The team are expecting to easily beat that record. “We didn’t come here to do 75km/hr.” says 2013 team project director, Sam. The race will consist of 120 laps of the 4.2km track at the Australian Automotive Research Centre proving ground.
Project Director, Hayden Smith, says the UNSW project began in 1995 with a team from a range of disciplines including mechanical, electrical, software, renewable and photovoltaic engineering. “Furthermore, we have students from other faculties contributing to the team – arts, media, design, business, science – the list is endless. It’s by far one of the most academically diverse undergraduate student groups at UNSW,” says Hayden.
The committed team of engineering students swarm over the car, changing tyres, adjusting tyre pressures, checking connections, and mounting their ‘piece de resistance’, a short aerodynamic tail designed to improve the already impressive aerodynamic by another 5%. Finally the aerodynamic wheel covers are taped on.
There’s a large Confederation of Australian Motor Sport (CAMS) team scrutinising the vehicle, locking off the solar panel connections and mounting the lap transponder. After they go over the vehicle with a thorough series of safety checks, Garth Walden, driver for the ELMOFO EV race vehicle, climbs in and mounts the removable steering wheel. After getting strapped in to the race harness and completing radio checks, the door gets taped shut for aerodynamic advantage.
Finally, with CAMS approval, eVe heads out with a quiet whir for a shakedown lap. As it flys past the pits, the team cheer it on as the radar gun clocks it at 110 km/hr. It’s quietness is a true sign of the efficiency of this vehicle at these speeds.
With all set and a nod from the timekeeper, eVe sets out on her goal: 120 laps of the 4.2km track in the shortest time possible.
The design of the 2-seater car is impressive. With such high aerodynamic performance (a CdA under 0.2) and a lightweight carbon fibre body, its energy requirements are more on the scale of household appliance rather than a road-going vehicle.
Eventually the fog lifts, and so do the spirits of the team as, lap after lap, eVe performs faultlessly. There’s a scheduled pit stop planned for lap 60, but on lap 53 the car blows a front right tyre. The car travels a few more kilometres to complete the lap and return to the pit area, running only on the rim of the carbon fibre wheel. The team was fully prepared and after a quick and smooth seven minute pit stop to change drivers and both front wheels, CAMS driver Karl Reindler heads out for the second half of the day. Seeing the chase/support car being refuelled during the pit stop provided an interesting contrast to the zero emission eVe.
The post-mortem on the blown tyre shows it was heavily worn, but had failed when an object had pierced the sidewall. Even so, the team is focused on their goal and plan for a second pit stop. On lap 97, in only four minutes, they change the front right wheel (taking the cornering load) and Garth heads out again to finish off. Karl clearly enjoyed himself: “I could do that all day; it’s comfortable, relaxing, but the racing seat is hard on the lower back!”
Egged on with cheers and waves, eVe crosses the line, completing the 120 laps in just over four and a half hours giving an average speed of well over 105km/hr (the actual record confirmation is an International FIA process that takes up to a month). The sense of relief and celebration is obvious, but also interesting is the team’s confidence in their vehicle during the day. They clearly had no doubt that they we’re going to comfortably break the existing record. We look forward to a friendly rivalry of teams with stunning designs like this attempting to break the new record.
The following puts eVe’s effort in context.
Vehicle Energy used to travel 500km*
UNSW Sunswift eVe 20 kWh @ 107 km/h 
Nissan LEAF 86 kWh @ 89 km/h 
Tesla Model S 67 kWh @ 89 km/h 
2013 Toyota Corolla 238 kWh @ 62.6 km/h 
 20 kWh approximate – it’s still a race vehicle so there are secrets
 highway cycle, 24kWh pack @ 80%DOD, 4.5 charges
 85 kWh pack @ 80%DOD (510 km range = 0.98 charge)
 E170/2013 model, ADR 81/02 22.214.171.124 ‘extra urban’ = 5.4lt/100km, 8.8 kWh/lt for 91 octane fuel.
It’s pretty hard to compare these test conditions and vehicles, but it’s still possible to say that eVe uses roughly one-quarter to one-third of the energy of a ‘normal’ electric car and maybe one-tenth of that of a petrol vehicle.
To become road legal eVe will need lights, a higher running height, a safety glass windscreen some latches and stronger hinges for the doors and possibly side impact protection. That will add some weight, but would still come under 500-600kg and be capable of travelling 400+km at highway speeds. If current EVs with that capability are high-end sports vehicles using up to four times as much energy, storing all that energy means larger battery capacity and therefore cost. Through great design the UNSW Sunswift team have demonstrated a way to break the price/range problem.
The spaghetti wiring and raw internal look clearly shows that this isn’t a production vehicle, but those are relatively trivial things to change. The basic vehicle is a true candidate to become a road going hypercar. Exciting times!
Controller: 2x Tritium Wave Sculptor 22
Motors: Two rear wheel motors based on the winning CSIRO design, bought in and then re-engineered. These motors have a peak power output of 10kW, 20kg weight per wheel, 97% nominal efficiency and normally run at 1-2kW.
Solar array: The 4 m2 array is considered to be a range extender. The Sunpower monocrystalline solar cells have 22% efficiency (after encapsulation) which equates to about 880W for the array.
Battery: The lithium ion battery used for the record run weighs 100kg and has
20kwh useable capacity (12 hours to charge). The nominal system voltage is 140 volts
Battery Monitoring System: Custom system that monitors individual cell voltage and temperatures and also the total energy used from the battery pack.
Tyres: Michelin special order low rolling resistance (LRR) tyres.
UNSW Sunswift www.sunswift.com
Tags: electric cars
This entry was posted on Monday, August 18th, 2014 at 3:05 pm