Surging petrol prices mean even bigger savings for electric vehicle owners

Back in 2019 I tried to answer the eternal “how long is a piece of string?” question when it comes to what it costs in electricity to run an EV.

With the spikes in petrol prices as well as the fall in EV prices resulting in more and more EVs on the roads and/or intentions to buy one as the next vehicle, it seems a good time to revisit the topic.

With petrol prices in Australia spiking to $2.38 per litre and beyond recently, this time I’ll recast the numbers using this worst-case petrol figure, as well as look at what different electricity prices can do to the equation.

For this revised example, I am picking the Western Australian electricity price ‘EV Add On’ electricity tariff structure from Synergy. I would suggest this tariff structure is a good example of one that reflects the growing use of renewable generation and the resultant shifts in periods of high and low electricity supply capacity.

First-up, the assumptions:

• Annual average distance driven per light passenger vehicle in Australia1: 11,100 km
• Average kWh/100km for an EV2: 15kWh/100km
• Average petrol consumption for light passenger vehicles in Australia1: 11.1L/100km
• Recent worst-case petrol price during school holidays: $2.38/L. Brisbane, mid-September.
• Low electricity tariff: 8.2c/kWh. Synergy (WA) super off-peak rate, 9am to 3pm.
• Overnight off-peak rate: 18.45c/kWh. Synergy (WA) 11pm to 6am.
• General off-peak rate: 22.55c/kWh. Synergy (WA) 6am – 9am/9pm – 11pm.
• High electricity tariff: 51.2c/kWh. Synergy (WA) peak rate, 3pm to 9pm.

Calculations:

• Average annual EV electrical use: 11,100km x 15/100 = 1665 kWh per year.
• Fuel used for an ICE vehicle at 11.1L/100km and $2.38/L over the same distance: $2809.18

So let’s put the above together to see what that means for average EV recharging versus average petrol car costs using different tariffs for 11,100kms a year.

Summing up: even if you charged your EV at the highest peak rate, the ‘average’ BEV recharging cost is still only 30% of the ‘average’ ICE vehicle petrol cost. If sticking to the Super Off-peak rate, recharging costs are less than 5% of petrol costs.

And, of course, the gains will be even more significant if your EV does 20,000kms, or 30,000kms a year.

Sadly, the figures provided by the Australian Bureau of Statistics for average litres per 100 km for passenger vehicles worsened from 10.8 L/100km in 2012 to the last year it was calculated in 2020 (11.1 L/100km). It would not surprise me if that figure has worsened still since then.

This provides yet another argument for the urgent need to bring in Australian fuel efficiency standards that reflect the falling L/100km figures in almost all other OECD countries.

Feel free to recalculate the numbers based on your own vehicle petrol fuel economy/price and electricity tariffs – although you do get a lot of better electricity price options than you get from petrol stations in the ever annoying price cycle that always seems to hit a high during school holiday periods.

By the way, even with the notorious Victorian EV Tax, for 11,100 km this only adds $311 to the annual fuel bill for those EV drivers residing there.

Mind-you, with those electricity tariff structures and the lifestyle options offered in such a large and diverse state – I wonder how long it will take for the WA government to start a campaign to attract interstate EV owners to move to WA?

And, as Sophie Vorrath reports in this article, some retailers are offering even better tariffs to those happy to be flexible. See: Ioniq 5 owner charges car for a month for less than cost of one litre of petrol

I will now finish with the same paragraph I ended that 2019 article:

Based on the above figures – it is inarguable though that an EV is cheaper to run than an ICE vehicle, plus the EV has reduced servicing costs, reduced wear on the brakes, and no tailpipe emissions adding to local pollution problems. The EV also has the capacity to continually reduce its energy CO2 emissions as the grid shifts from fossil fuelled to renewable sources: all unlike an ICE vehicle which is forever tied to running on carbon based fuels.

As a final, final note: if you want to calculate your own EV electricity running costs, the Green Vehicle Guide offers a useful calculator. It can be found at: https://greenvehicleguide.gov.au/Calculators/HomeChargingCalculator

Footnotes:

1. Australian Bureau of Statistics: Survey of Motor Vehicle Use, Australia, 12 months ended 30.6.2020 (data collection by the ABS on this topic ceased at that date).
2. A rough figure that I chose to be half-way between the lowest and highest values for the top 20 BEVs available on the Australian market (Source: Green vehicle guide. MG4 64kWh battery at 1.3kWh/100km and MG ZS EV at 1.71kWh/100km).