Science

Faster isn't always better. Slow-charging EVs could have big benefits

Thinking about an EV as your next car, but worried about where to charge it, and whether you'll need a pricey electrical upgrade to your home? If you have parking and a plug somewhere nearby, your home is probably EV ready, say those who have embraced 'slow' charging.

Level 1 charging is sufficient most of the time, experts say, using an outlet you probably already have

Woman standing beside car that is plugged in for charging
Julia McNally says she finds that Level 1 charging, using a regular wall outlet, is all she needs to keep her electric vehicle powered up. (Submitted by Julia McNally)

When Julia McNally decided to buy an EV and started her research, she came across a lot of articles and ads pushing an apparent must-have accessory — a speedy home charger designed specifically for EVs.

"Everything was pointing me to Level 2," recalled McNally, director of climate action at Toronto Hydro.

She knew that all EVs can do Level 1 slow charging, or "trickle charging," from a regular 120-volt wall outlet, adding about six kilometres of range per hour (except in very cold winter temperatures, which can slow charging speeds). And she already had an outlet of those in her backyard, near the alleyway where she planned to park her new Mini EV. 

But more than four out of five U.S. EV owners used Level 2 for home-charging in 2023, according to market research firm J.D. Power. Using a higher 240 voltage, often needed for a stove or dryer, Level 2 chargers can add about 30 to 50 kilometres of range per hour and refill a typical EV's entire 400-kilometre range overnight.

Meanwhile, Level 3, or DC fast chargers, often installed along major highways, can add 250 kilometres of range per hour (some are even faster) and charge a battery to 80 per cent in 30 minutes.

Why faster may not be better

Some experts, such as Daniel Breton, CEO of Electric Mobility Canada, have argued people "really need" Level 2 chargers at home, as it can take days to charge an empty battery to full at Level 1.

But most people don't drive the hundreds of kilometres needed to empty their battery each day — and there's a downside to faster charging.

"You're adding cost," McNally said — potentially thousands of dollars.

Installing a Level 2 charger requires a licensed electrician, she said. In Toronto, it means consulting with Toronto Hydro and the Electrical Safety Authority. And homeowners often will need to increase the size of their electrical panel, adding additional costs.

But it's something more Canadians may be thinking about soon, amid Canada's zero-emission vehicle mandate, requiring that 20 per cent of cars, vans and light trucks sold in Canada be electric, hybrid or hydrogen-powered cars by next year. The goal is to reach 100 per cent zero-emission vehicle sales by 2035.

Conservative Leader Pierre Poilievre had vowed to scrap the target if elected, but with a Liberal re-election, the target still stands.

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Level 2 charging isn't just more expensive and logistically difficult for individual EV owners. In some Canadian communities, the aging electrical grid may not be able to handle too much Level 2 charging at once.

For example, a recent Yukon University study found that if more northerners install Level 2 chargers and electric heating, that could cause problems for transformers — a key piece of equipment in local electricity distribution networks. (However, it found electric heating would be a much bigger issue than EVs).  At the time of the study, published last December, there were 344 EVs in Yukon, a third of them plug-in hybrids, and only 88 EVs in all of Northwest Territories, half of them plug-in hybrids.

Blake Shaffer, a University of Calgary associate professor, studied the situation in his community with local utility Enmax. He previously told CBC News that electricity distribution networks would need "significant" upgrades in order for all EV drivers to be able to charge at Level 2.

"That's where the real challenge of EVs comes about," he said, noting high costs for both individuals and electric utilities.

McNally says Toronto Hydro has adequate capacity for "whatever EVs and heat pumps come at us." She acknowledged, however, that in cases where someone does ask Toronto Hydro for extra capacity "you need to pay for the upgrades."

Meanwhile, Level 1 takes advantage of wall outlets that people often already have, including residents of apartments or condo buildings. In colder parts of Canada, many parking spaces have a plug intended for block heaters. (Although tenants may have to negotiate with their landlord to use it for charging.)

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Many people don't need Level 2 at home

Living in Toronto, McNally doesn't drive 400 kilometres a day; typically, she only covers 600 kilometres in an entire month. So she knew that Level 1 charging was probably good enough for her needs.

That's not unusual — even outside Canada's largest city.

Shaffer studied the driving and parking habits of 129 EV drivers in Calgary from December 2021 to December 2022. (While that was during the tail end of the pandemic, Statistics Canada reports very similar commute times in Calgary in 2022 and 2024.) The study found 29 per cent of drivers only ever needed Level 1 charging because they drove very little relative to the time they were parked. Another 53 per cent could use Level 1 most of the time, but might need to visit a public Level 2 or fast charging station up to once per month to top off their battery.

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The City of Vancouver estimates that the average driver can meet their daily driving needs in under four hours using a Level 1 charger and in about 45 minutes using a Level 2 charger. Either of those is plenty of time if people have a place to park and charge overnight.

Level 1 can even work for drivers far from Canada's biggest cities.

Rob van Adrichem lives in Prince George, B.C., and got an electric car this past summer. He only has Level 1 charging at home, but tops up at Level 2 chargers at the park or the library in town if he needs to. 

"I'm finding Level 1 is no problem," he said. "I think people get scared off on Level 2s  because they think it's going to be thousands of dollars and I don't know that it's always necessary."

Ali Mohazab is co-founder of a startup called Parkizio Technologies that helps people such as apartment dwellers access electricity for charging. He said people thinking about switching to an EV may imagine doing a variation of what they did with their gas car: driving to empty and then going to a gas station and filling the entire tank — something they're forced to do because they don't have a gas pump at their home. 

Mohazab said that "gas mentality" may not allow people to see that with an EV, "every parking opportunity is a charging opportunity" and it doesn't matter if you charge faster so your battery is full at 1 a.m. instead of 8 a.m. when you leave for work — you can just leave it plugged in overnight. He added, "If you kind of look at your car as a, you know, cell phone with wheels, then it really makes sense."

McNally has found that she doesn't even need to charge every day, even at Level 1. "I charge about once a week," she said. "Couldn't be easier."

But how can you tell if Level 1 will be enough for you?

Level 1 is probably enough for most people, Mohazab says, except those who drive all day for work, such as Uber drivers.

McNally suggests this rule of thumb: "If you drive less than 60 kilometres a day, you are probably just fine with the regular plug that is already at your house."

She recommends that new EV owners start with Level 1 to keep things cheap and simple.

"Start there, see how it works, learn your patterns — and then if you really want Level 2, you can add that cost later."

Corrections

  • A previous version of the story said at the time of the Yukon University study, there were only 88 EVs in Yukon, half of them plug-in hybrids. In fact, that figure was for the Northwest Territories in March 2024. In Yukon, there were 344, a third of them plug-in hybrids.
    May 02, 2025 8:02 AM EDT

ABOUT THE AUTHOR

Emily Chung

Science, Climate, Environment Reporter

Emily Chung covers science, the environment and climate for CBC News. She has previously worked as a digital journalist for CBC Ottawa and as an occasional producer at CBC's Quirks & Quarks. She has a PhD in chemistry from the University of British Columbia. In 2019, she was part of the team that won a Digital Publishing Award for best newsletter for "What on Earth." You can email story ideas to [email protected].

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