The complexity of the calculations behind electric car efficiency is highlighted by a recent report from CHOICE magazine. CHOICE is highly regarded in Australia for providing excellent advice to consumers regarding product purchases. However, I questioned what I believed to be poor assumptions underpinning their advice to consumers. See their report on electric cars here.
After I gave my feedback, what followed was an honest and open conversation with Peter Giles, Product Innovation Manager at CHOICE. The article is an exploration of that conversation and is published with permission from CHOICE.
CHOICEPeter Giles: “Just to clarify – I work on a team looking for new ways to engage our audience. We did some research where we interviewed a lot of EV owners and also people who intend to buy an EV soon. We found that the people who intended to buy an electric car wanted more information about running costs, range, charging and batteries. They also said they wanted a simple guide that provided clear and precise information to help them research the area. We created a Quick Start EV Guide as an online guide to help them with their research. This is not really a report as such, just an attempt to condense the information into an easily accessible guide.
“Also keep in mind that the EV Guide is a prototype we’ve just launched and we’re still gathering user feedback – and will look to update it based on that.”
Let’s take a look CHOICE‘s analysis. First up are the operating costs. CHOICE comparing a Corolla petrol sedan to an MG ZS EV. It’s not a fair comparison.
CHOICE: “[A] Camry benchmarked against a Model 3 might be a good way to go. It was difficult to choose the electric car to benchmark – initially we looked at the Hyundai Kona, which has a hybrid, petrol and electric model – but the hybrid is not on sale in Australia.
“We went with the MG because it sold well and is affordable, but I take your point that the Tesla Model 3 is by far the biggest seller of any electric car in Australia so far – I think a Toyota Camry probably would be the most equivalent sedan in hybrid and petrol variants. We’ve also had some feedback that perhaps we should have benchmarked against a larger SUV like a RAV4 – perhaps we could do this once the Model Y has caught on (and I’m sure it would look much more favorable to the electric cars) .”
Next: Petrol costs are assumed to be 4 times the cost of electricity. I pay 13¢ a kWh at best and 24¢ at worst. CHOICE assumes a price of 30¢ per kWh. Gasoline costs $1.80 per gallon today. Petrol can be up to 8 times the price of electricity.
CHOICE: “With electricity prices, we generally work with 30¢/kWh – when you take into account utility charges etc. it can be around this on average – of course depending on when you use the car. If you paid to charge at a fast charging station, it would be more. Electricity prices are rising at the moment.”
The other assumption I questioned was that they expect you to pay the same amount to maintain an electric car as you would for a gas car – allocating about $300 a year for servicing.
CHOICE: “Point taken on maintenance costs – if you have better data sources than EVENERGI (who provide backend data to the NRMA and EV Council website, I would appreciate any recommendations – we have used their data for the benchmarked vehicles.
“I think our choice of cars may have influenced this as well, as Toyotas are quite cheap to maintain (compared to say a Mercedes). Apparently the EV Council estimates that petrol cars cost around 7¢ per litre. km in servicing costs, while EVs are around 2¢ per km in comparison. Do you think this would be a fairer comparison for us to use? From my understanding, EVs cost a bit more for tires as they are heavier.”
The information on charging speeds and times seems reasonably accurate. However, I asked about charging from 0% to 80%. Most electric drivers don’t let their car run down to zero before plugging in.
CHOICE: “Thanks for your point about charge times – on our driving range tool we actually estimated 20-80% charge, so maybe for consistency we should update the estimates on the landing page – I’ll look at updating this on your suggestion.”
Then we come to environmental impact, where the report shows in a graph that an electric car charging from the current NSW grid produces more carbon dioxide than a hybrid car running on petrol alone. A quick check of the NSW grid shows it’s running on 40% solar at the moment. So these numbers can’t possibly be true.
The Australian grid is becoming greener at a rapid pace, and this needs to be taken into account.
CHOICE: “Finally on CO2 output we have calculated this based on the NSW grid (equivalent to QLD and VIC) – about 70% from coal currently according to National Energy and Greenhouse Reporting – 2021 But our modeling takes into account the growth of renewable energy over the next 5 years – a reduction of around 10% emissions per year in NSW We included the solar section to emphasize the huge cost benefits of being able to generate your own renewable energy (and charge up during the day) .”
CHOICE goes on to point out that an EV battery has an 8 year warranty and should be cheaper to replace after that time. The assumption is that an EV battery will hit 100% degradation during the warranty period. These kinds of comments can perpetuate the belief that EV batteries need to be replaced frequently.
CHOICE: “We generally point out the time that EV batteries are under warranty – we don’t mean to suggest that it needs to be replaced in 8 years, but that battery costs will be significantly lower by then.”
It’s great to see a magazine with a quality reputation CHOICE to give advice to those who want to “change”. I really appreciated the opportunity to engage with them in a frank and informative conversation. They are looking for feedback, what do you think?
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