Electric cars are an imminent threat to the power grid unless we change our behavior

Electric cars could increase demand on the electricity grid during the evening peak by at least 30% unless households adopt smart charging, according to a new trial.

Origin Energy has partnered with the Australian Renewable Energy Agency (ARENA) to understand ways to change the behavior of electric car owners ahead of their mass adoption in Australia.

With the threat of blackouts a reality amid higher prices and demand, Origin’s e-mobility general manager Chau Le said the network will struggle once electric vehicles became more popular.

“At the moment, our power grid is not doing well at all,” she said.

“If we were to add an additional 30% of peak load to the network during these times of high prices and constraints on the network, it would require significant investments to increase capacity.”

To manage the looming threat, Origin and ARENA tested “smart charging”, the results of which were released yesterday.

Smart chargers, costing between $2,000 and $3,000, were installed in the homes of 150 EV users and baseline data collected.

Chargers allow people to set their charging times, for example when there is more low-cost renewable energy being produced or to support the grid during times of peak demand.

He found that without intervention, 30% of recharges were made during the evening peak, between 3 p.m. and 9 p.m.

However, Ms Le said participants were very engaged and early adopters of the technology and that many regular motorists may not pay as much attention to optimal charging times.

How they changed the charging behavior of electric vehicles

The first trial saw participants receive a 10 cents per kilowatt-hour credit on their electricity bill for off-peak charging.

This reward reduced load during evening peak to 10%, a 67% decrease from baseline.

The second trial saw Origin take the reins of charging times to limit them mostly to off-peak hours through a “plug-in and forget” method.

They could even react with agility to “critical peak events”, as seen at the beginning of last weekto turn off any load.

This method reduced evening peak usage to just 6%, an 80% decrease from the baseline.

Despite the incentives leading to significant behavior change, EV drivers still charged during the evening peak between 6-10% of the time.

“If that 6% is all in one network patch, it will have a magnified impact on that local substation or local connection,” Ms Le said.

Ms Le said the third part of the trial, which is ongoing, would see Origin work with power distributors (Citipower, Powercor and United Energy) to understand whether the grid would need to be upgraded to meet the baseline usage observed in trials, once mass adoption of electric vehicles takes place.

ARENA chief executive Darren Miller said he funded $840,000 of the $2.9 million trial, adding that three more with retailers and distributors were also underway across the country.

Mr Miller said ARENA, an independent federal government agency, was investing in research because it was “very concerned” about what might happen when electric vehicles become more popular.

“Additional investments will have to be made and it will also cost us all on our electricity bills at the end of the day.

“I think if we do it really well, we might expect there wouldn’t be a lot of extra cost from the distribution companies.

“We can ensure that we don’t have to invest an extraordinary amount of money in the distribution system, poles and wires outside our homes and businesses, to cope with this additional load.”

Electric vehicles are expected to become more popular from 2025when the price of batteries is expected to drop so much that cars reach price parity with traditional vehicles.

Mrs Le pointed to search this showed that if electric vehicles made up 80% of new car sales by 2030 and were all plugged in during the evening peak, instantaneous charging would double peak electricity demand.

“I am very confident that we will obtain a cost advantage”

The final trial document is due in December, but Ms Le said early results showed that the financial rewards helped get drivers to charge during off-peak hours.