According to modelling from the Monash University Energy Institute, unmanaged EV (electric vehicle) charging during evening peak periods could significantly increase electricity demand and drive additional infrastructure costs across the network.
Battery electric vehicles accounted for 14.6 per cent of new car sales in March 2026, according to the Federal Chamber of Automotive Industries’ VFACTS data. This reflects the sector’s continued growth as Australia accelerates transport electrification.
Researchers said the issue to solve is mainly when charging occurs. Evening periods already represent the highest demand window for the grid, as solar generation declines while households simultaneously increase electricity consumption.
The institute’s submission to the Victorian Parliamentary Inquiry into Electricity Supply for EVs modelled two future charging scenarios using the Monash Renewable Energy Integration Lab framework.
One scenario reflected ‘convenience charging,’ where motorists plug in after returning home between 5pm and 9pm. The second modelled a more ‘grid-friendly’ approach, shifting charging into daytime and overnight periods when renewable generation and spare network capacity are more readily available.
The modelling found that by 2050, unmanaged charging could push peak demand to around 100 gigawatts, compared with approximately 50 gigawatts under managed charging arrangements.
Associate Professor Julie Karel, Department of Materials Science and Engineering, explained that the findings highlight the importance of aligning EV charging behaviour with renewable energy generation profiles.
“It’s tempting to think the problem is simply ‘more demand’, but electricity systems don’t usually fail because demand increases gradually. They get stressed when everyone wants power at the same time, in the same few hours,” Professor Karel said.
“The modelling shows that by 2050, peak demand is about 100 gigawatts under unmanaged evening charging, compared with about 50 gigawatts under grid-friendly charging.”
“But if charging is shifted into daytime hours when solar is strong, and into quieter overnight periods, EVs can actually help the system by using clean energy when it’s available and easing pressure later on.”
The submission identified workplace charging, public ‘solar sponge’ charging hubs and managed overnight charging as key mechanisms to reduce pressure on evening demand peaks. It also pointed to the role of time-of-use tariffs, smart charging standards and default managed charging systems in shaping consumer behaviour.
The research also highlighted equity challenges associated with EV infrastructure access. Monash University research found that while most Victorian EV owners or prospective buyers prefer home charging, many apartment and unit residents lack access to private charging infrastructure. Researchers warned this could leave renters and apartment dwellers dependent on more expensive and less convenient public charging options.
The submission further examined electrification impacts for large vehicle fleets, including buses, noting that localised charging demand at depots may create network stress despite relatively small increases in overall electricity consumption.
Researchers argued that future policy settings, pricing structures and charger deployment strategies will play a central role in determining whether EVs place additional strain on the grid or support a more flexible and renewable-focused electricity system.
For more information, visit the Monash University website.
