EV mythbusting: Grid stability and road damage

‍In the next in our series plugging you into the facts about electric vehicle charging, batteries, affordability and more, we take a look at the impact of EVs on the electricity grid, the health of roads, and other weighty issues.

Do electric vehicles take more than they give? If you believe some popular myths, they’re like a hot but evil reality show contestant: good looking, for sure, but high maintenance and doing untold damage on the quiet. Common claims by sceptics and the misinformation brigade: that the electricity grid won’t cope with mass charging of EVs, that roads will be damaged by their weight, and even that they will collapse multi-storey carparks.

This is weighty stuff, requiring a serious fact-check.

EVs and the grid

In Australia, states and territories have set targets for electric cars to represent 50 to 90 percent of total car sales by 2030. sSales of EVs have doubled since 2022, and are climbing despite the odd blip. When half the nation’s car owners – let alone all of them – are driving electric, will the electricity grid cope?

For answers, let’s go straight to the Electric Vehicle Council of Australia, which has been collecting data to address those claims the grid will fail.

The first thing to understand, according to the EVC, is that while there will be more demand on the grid, this won’t happen overnight: “If every car on Australia’s roads today was to become electric, this would result in around a 15% increase in overall electricity demand. Given this transition will occur over the next 25 or so years (in order to achieve net zero by 2050), there is more than enough time for this level of new energy generation to come online.”

In the meantime, Australia is already charging in smart ways that not only reduce sudden impact on the grid, but can actually make it more resilient.

In a recent report titled “Home EV charging and the grid: Impact to 2030 in Australia”, the EVC notes that: “Most at-home EV charging currently takes place either in the middle of the night or during the middle of the day, with relatively little charging occurring during peak periods.

“Assuming this behaviour continues and the uptake of EVs aligns with government targets for 50% of new vehicles to be EVs by 2030, the contribution of EVs to peak demand by 2030 is likely to be limited to about 1% of total grid peak demand.”

Essentially, it’s predicted an increasing number of people will charge at home overnight, taking advantage of cheap, off-peak electricity rates, and the middle of the day, when solar energy is abundant on the grid. This reduces costs, helps to stabilise the grid – and of course benefits the environment. 

When it comes to public charging, there are positive signs that drivers can be encouraged to behave in ways that support the grid. In partnership with the South Australian Government, Chargefox conducted a trial that aimed to explore whether time-of-use pricing strategies can encourage drivers to charge during periods when solar energy is abundant and wholesale energy prices at their lowest. Our findings: indeed they can.

You can read more here about the recent study Chargefox conducted with support from the South Australian government.

Giving back

Managing the time of day that EV owners plug into the grid is one thing, but what if EVs could actually contribute to the energy supply? After all, the average EV battery stores enough electricity to power a household for two days or more than 4 times that of the popular Tesla Powerwall 2 home battery. The idea is that the car battery acts as a portable power pack, allowing drivers to power their homes or sell power back to the grid when demand is high. Win, win.

This is not the stuff of science fiction: carmakers including BYD, Hyundai, Renault and Nissan are already installing the technology that makes bi-directional charging possible. 

In Australia, we have the technology and products for vehicle-to-grid transmission, and this month (November 2024) came the regulatory breakthrough, Energy Minister Chris Bowen announcing that “Standards Australia has ticked off the new standard that will allow vehicle-to-grid charging in Australia”. Manufacturers and charging companies will apply to the Clean Energy Council to have their product approved, with hopes bi-directional charging will be “a reality by Christmas this year”.

“It’s about ensuring grid stability, and it’s about ensuring maximum use of every single electron– ensuring consumers get maximum value from their assets.” Minister Bowen said.

The bottom line: with advancements in grid management, increased renewable energy supply, regulatory support and better understanding of consumer charging behaviour, there’s no reason to fear that a nation of EV drivers will be left in the dark.

A weight problem?

It’s a persistent argument against EVs: their batteries make them heavier than their ICE counterparts, so surely that means more damage to roads … and wasn’t there a story about a multi-storey carpark collapsing under the weight of EVs? (Spoiler alert: yes, there was a made-up tabloid story, which has become an urban myth, and no it didn’t happen.)

Even our friends at the NRMA have weighed in with the headline: “EVs are heavy. Are they safe on our roads and carparks?” While the NRMA doesn’t exactly answer that question, a recent study by engineers at University of Technology Sydney (UTS) gets to the heart of the matter with a report titled “Do battery electric cars significantly increase average fleet mass? Unlikely.”

The UTS report explains: most popular electric cars sold in Australia are relatively light, while the best-selling fossil-fuelled cars are now relatively heavy SUVs or utes. (In 2024, Australia’s most popular ICE vehicles are the Toyota Hilux and the Ford Ranger, each weighing more than 2500kg. By comparison, the most popular EV, the Tesla Model Y, weighs 2000kg.)

“When adjusted for actual top 10 vehicles sold and using realistic mass values, the average mass of battery electric and fossil-fuelled cars differs by just 68kg,” wrote the report’s author, Robin Smit. “That difference is not significant, especially because electric cars are much more energy efficient.”

There’s no denying the safety issue: our roads and car parks, especially those built last century, must be tested for their ability to stand up to the pressures of the modern passenger vehicle. 

Anecdotally it seems that many who are most vocal about the weight of EVs being an issue are also more likely to favour big SUVs and American style pickup trucks.

As the UTS report concludes, in the face of an alarming trend towards “car obesity” – the emergence of ever larger, heavier cars of all kinds – claims that EVs do the most damage just don’t stack up.

‍Sources:

Electric Vehicle Council: Can the current energy grid handle the increasing number of electric vehicles on the road?

The Guardian: Sceptics say EVs will overwhelm the grid. In fact, they could be part of the solution

The Conversation: Electric vehicles can provide the backup Australia needs

DCCEEW: Standards Australia will allow vehicle to grid charging in Australia

Chargefox: Smart Charging Trial

The Conversation: Do EVs greatly increase the average mass of cars on the road?

NRMA: EVs are heavy. Are they safe on our roads and carparks?  

The Driven: Weight of electric vehicles will not crush bridges, car parks, or the planet

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