Trial complete: Electric vehicles can work in Australia

The Conversation

Australia’s first electric vehicle trial has been completed. It ran from early 2010 to the end of 2012 with 11 electric Ford Focus and 23 fast-AC charging bays (Level-2). We found few technological barriers to the adoption of electric vehicles (EVs) in Australia, but government incentives for early adopters and government programs for the roll-out of fast-DC charging stations would help Australia fully embrace these cars.

The cars

When we started the trial, no electric cars from major manufacturers were available in Australia. Because of this, we used converted Ford Focuses. The conversions were performed locally by WA company EV Works. Each car was equipped with a 23kWh battery pack, a 27kW DC motor and a 1000A motor controller.

The cars were used as regular fleet vehicles by our 11 project partners from government and business, demonstrating their usability for everyday driving.

The cars achieved a road-tested driving range of 131km on a single charge (dynamometer testing resulted in a 143km range). This significantly exceeds the driving range of a Mitsubishi i-MiEV, which achieved a 112km range under identical road-test conditions.

Fleet of Electric Ford Focus

The charging stations

We installed 23 charging stations for Level-2 fast-AC charging around the Perth CBD. We adopted the international charging norm IEC 62196 with European “Type-2/Mennekes” connectors, which have two advantages over “Type-1/J1772” charging stations:

• They can charge EVs with either Type-1 (US/Japan) or Type-2 (Europe) inlets.
• They can provide three-phase power, which charges three times faster and achieves a better grid balance.

At these stations, an EV can be charged in about 3.5 hours from empty to full. A slower home charge on a standard 10A power socket will take around 10 hours.

Data collection and software development

Data logging

Data was recorded from the vehicles as well as the charging stations through data loggers and 3G modems. This gave us a full picture of vehicle movement and charging patterns. We could record the vehicles’ driving paths, charging times, their use of air-conditioning, heating and other major energy consumers.

Our team also developed a smartphone app that is especially useful for drivers to check their EV’s status while the car is on charge. This will let the driver know whether charging has finished and the car can be collected or whether it needs to charge somewhat longer.

When are cars charged?

We were particularly interested in what time of day drivers charged their cars. This determines how much renewable energy can be used for charging (to make an EV really emission-free) and whether electricity utilities have to worry about an increase of peak demand in the future, when there might be millions of EVs. The graph below summarises the results.

Charging summary over time of day

The fleet EVs did most of their charging in the morning until mid-day, so most of the charging energy could be supplied by solar photovoltaics. This finding is significant, as company fleets are not only an early adopter of new car technology, but are also the largest customer segment for the new vehicles market in Australia.

We also looked at power usage over the trial period for public charging stations only. Even more pronounced than the overall charging curve above, charging at public charging stations happens during the day with a peak around 10-11am and a curve that almost ideally matches a solar PV curve (see the graph below).

Charging station usage in terms of power

The blue bars indicate the amounts of energy required to actually charge the EVs, while the smaller red bars indicate the amounts of energy required to maintain a plugged-in car at full level, once charging has been completed (most charging stations do not switch off once charging is completed, but continue to deliver small amounts of energy to keep the EV at the fully charged level).

We also looked at charging events in terms of “hours spent” at the charging station, rather than “energy used”. This gives a completely different picture (see graph below).

Charging station utilization in terms of time

The times required to complete the actual charging (shown in blue) are relatively minor, compared with the overall time spent just parking at the station (red). Since both energy and parking were free for the duration of the trial, obviously charging stations have often been mis-used as free parking spots, without a real need for charging.

This is not ideal, of course, because it will block charging stations for other EV owners, who may have wanted to use them. Applying standard fees for parking and power would most likely change this behaviour.

Recommendations

We found:

• EVs can function as regular fleet pool cars for most applications.
• The daily charging curve for fleet EVs and public charging stations can almost completely be covered by solar PVs, resulting in truly zero emission transport.
• Without a fee structure, Level-2 (7kW) charging stations (or even Level-1, 2.4kW) are difficult to use effectively with multiple customers per day.

There is a “chicken and egg” problem in introducing EVs and charging stations. Potential EV buyers expect a certain level of charging infrastructure, while potential charging network operators are reluctant to invest before a critical mass of EVs is reached.
Some form of government financial incentive would help to increase the initial uptake of EVs in Australia.

The vast majority of charging events will likely occur at home or at work with only the occasional need for using a public charging station. A network of fast-DC stations can serve the same purpose as a filling station network for petrol/diesel cars.

We recommended that a network of fast-DC stations (50kW or more) following the CCS-Combo standard be installed, which may prove much more efficient and useful than lower-powered AC-charging stations (Level-2 or Level-1).

The Electric Highway proposal with fast-DC stations between Perth and Margaret River would make an excellent demonstration project. It will allow electric vehicles to break free from the city and reach a popular holiday destination as well as major regional centres.

The lack of an Australian standard for an EV charging connector is seen as a significant hurdle for EV adoption as well as for the roll-out of charging stations. Failure to prescribe a particular connector/inlet type could lead to the import of cars and charging stations which are incompatible with one another.

Additional research is required to better understand potential positive and negative implications of large numbers of EVs on the electricity network. This requires the cooperation of energy utilities, government policy makers, EV industry, and universities.

The full WA EV Trial report is available from UWA/REV.

Thomas Bräunl is Professor of Robotics; Director, WA Electric Vehicle Trial at University of Western Australia.

He worked for the WA EV Trial consortium as Technical Director. EV Trial participants were: CO2Smart, UWA/REV, EV Works, City of Perth, City of Swan, City of Mandurah, Landcorp, Water Corp, WA Dept. of Transport, WA Dept. of Environment and Conservation, RAC WA, Telstra, Mainroads, The West Australian.

ARC Linkage partners are UWA Eng., UWA Business School, Murdoch Univ., AEVA, WA Dept. of Transport, Co2Smart. Station sponsors are Galaxy Resources and City of Fremantle.

This article was originally published at The Conversation.
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