The
University of Queensland
Sustainable Energy Research
Group
The UltraCommuter
The UltraCommuter has been the flagship project of the SERG. In 2007 the project was transferred to the University of Waitako in New Zealand with members of the original UltraCommuter team forming a new venture HybridAuto Pty Ltd.
This page and the archive section of this website contains more information on the early development of the UltraCommuter.
Click here è for large exterior view (152kb),
or interior view (94kb)
Cars as we know them are unsustainable -
consumption of fossil fuels and raw materials for vehicle propulsion and manufacture
produces environmentally damaging pollutants and contributes to depletion of
natural resources. At end-of-life,
various pollutants and emissions derive from vehicle dismantling and recycling,
while millions of tonnes of automotive scrap are buried annually as landfill.
Furthermore, in Australia, the
typical car is remarkably over-engineered for the majority of its use. A Holden Commodore (the most popular selling
car in 2002) offers 5 seats in a 1580kg package measuring 4.9×1.8×1.5m and will
travel over 600km on its 75L fuel tank.
Most cars, however, reside in urban areas being used for urban commuting
purposes on trips of less than 10km.
Average occupancy is 1.3 passengers with 2 seats being sufficient for
the vast majority of trips, while total cargo weight would normally amount to
less than 100kg. Clearly, the disparity
between the design of cars and their typical use holds many opportunities for
improvement!
Following
their success with the SunShark solar car, SERG members have embarked upon a
new project to demonstrate sustainable personal transportation options for
Australia. Designed according to the Hypercar philosophy, the
UltraCommuter sustainable vehicle concept is an ultra-light weight, low drag,
energy efficient and low polluting, hybrid-electric commuter vehicle optimised
for Australian driving requirements. Its
target market segment is fleet vehicles, or as the “second car”
that is commonly owned by Australian households.
Further elements of the UltraCommuter design concept are
outlined below:
·
Compact 2-seat commuter
vehicle with cargo area
·
Lightweight chassis with modular composite crash structures and
body panelling
·
High performance yet efficient electric drive train
·
Natural gas-fuelled range extender
Compact 2-seat commuter vehicle with cargo
area
To “fit” its role as a
sustainable commuter vehicle, the vehicle will be compactly-sized at
3.8×1.6×1.3m, providing two comfortable seats with ample boot space for extra
luggage.
Good aerodynamics is a key element of the
UltraCommuter design. This will be achieved
by minimising frontal area with a compact vehicle
design, and balancing
streamlining with natural forms and attractive styling. Low rolling resistance tyres will also be
used, along with a novel brake design implementation to eliminate brake drag. In combination, these will reduce the
UltraCommuter’s required cruising power to less than 6kW at 100kph.
Lightweight chassis with modular composite
crash structures and body panelling
A lightweight extruded/hydro-formed/bonded
aluminium chassis weighing 68kg will provide the backbone for the vehicle. It will be surrounded by modular bolt-on
composite crash structures designed to protect the backbone chassis and improve
impact energy absorption. Modular body
panelling constructed from non-dent, scratch resistant, recyclable
thermoplastic will attach to the vehicle exterior, doubling as bumpers for low
speed collisions. By focusing on
light-weighting throughout the vehicle, the UltraCommuter could attain a curb
mass as low as 500kg.
High performance yet efficient electric
drive train
The UltraCommuter will utilise high
performance direct-drive wheel motors in the rear wheels. This layout improves transmission efficiency
(by eliminating the gearbox) and reduces vehicle mass and overall part count
through the elimination of drive shafts, differentials, CV joints, half shafts,
etc. Further improvement comes with the
elimination of friction brakes on the rear axle, with the wheel motors providing 100% regenerative braking under normal driving
conditions (except in emergencies). The
drive train will
have a high peak torque capability of 1000Nm total, sufficient
to accelerate the vehicle at 0.5g and 0-100kph in under 8 seconds, and high
operational efficiency of greater than 90% under a wide variety of operating
conditions.
By equipping the UltraCommuter with a 2.5m2
on-board solar array, a key goal is to make it predominantly self-sufficient
from solar power for commuting purposes so that it will typically not require
charging or refuelling from off-board sources.
Research shows that the UltraCommuter’s on-board solar array can
power 87% of annual travel needs for an average QLD passenger vehicle. With solar supplementation, the vehicle also
has excellent potential to reduce annual greenhouse gas emissions from the
private transport sector, achieving a 97% reduction in CO2 emissions
when compared to the average QLD passenger vehicle. Lastly, the vehicle battery pack provides for
tolerance to consecutive days of poor weather without resorting to grid
charging, giving uninterrupted functionality to the user.
Natural gas-fuelled range extender
The UltraCommuter will be
equipped with a range extender to provide for long trips of up to 500km. Several fuel options have been considered for
the vehicle, with premium unleaded petrol, ethanol, compressed natural gas
(CNG), and compressed hydrogen (via a fuel cell) being the primary
candidates. CNG was ultimately selected
as the best fuel for the UltraCommuter since it offers numerous benefits as a
stepping stone in the transition to a sustainable energy economy:
• In
Australia, known natural gas reserves constitute more than three times the
known equivalent oil reserves.
• Natural gas
is the only fuel that requires almost no processing for automotive use.
• Natural gas
has the lowest carbon intensity of all fossil-based fuels.
• Natural gas
is a high quality fuel that burns cleanly and offers 10-15% engine efficiency
improvement over petrol due to its high octane number.
• CNG is
competitive on a “well-to-wheel” basis, displaying good performance
in full-cycle energy consumption and greenhouse gas emissions.
• CNG has
received substantial federal government backing through the $7.6 million
Compressed Natural Gas Infrastructure Program designed to establish a national
network of CNG refuelling stations in Australia.
• Natural gas can play a crucial role
as both feedstock and fuel in the transition to a sustainable hydrogen economy,
as described by Amory Lovins (1999) in “A Strategy for the Hydrogen
Transition”.
Table 1 below compares the
UltraCommuter with two representative Australian urban vehicles – the
Holden Commodore sedan and Toyota Echo 3 door hatch - which are commonly
purchased for fleet use and could potentially be displaced by the
UltraCommuter. Clearly, the
UltraCommuter is an attractive prospect, offering to reduce equivalent fuel consumption by 83% and greenhouse gas emissions
by 87% when compared to the benchmark Commodore. Furthermore, solar supplementation of the
UltraCommuter offers to increase these reductions to 96% and 97%
respectively!
|
Vehicle |
Curb Mass (kg) |
Equivalent fuel consumption (L/100km) |
Well-to-wheel GHG emissions (kgCO2/100km) |
|
CNG UltraCommuter with solar commuting |
520 |
0.44 |
0.85 |
|
CNG UltraCommuter |
520 |
1.9 |
3.7 |
|
Toyota Echo 3 door |
850 |
6.2 |
16.2 |
|
Holden Commodore |
1580 |
11.0 |
28.7 |
Table 1: Comparison of the UltraCommuter
with other urban vehicles
UltraCommuter Technical Specifications
Sustainable
Energy Research Group / Email
SERG
School of Information Technology and
Electrical Engineering / The
University of Queensland