ECRA/ESA licensed contractor Mon–Sat 7am–7pm 24/7 emergency callout
Barrie Electrical Co. (705) 555-0147

Guide

Can You Put an EV Charger on a 100 Amp Service?

How the CEC Section 8 load calculation actually works, why load management is usually cheaper than a service upgrade, and what both cost in Barrie.

Last updated
July 2026

The short version: probably yes, and probably not the way the first quote you get suggests.

The calculation nobody shows you

Section 8 of the Canadian Electrical Code sets out how to calculate the demand on a residential service. It is not a guess and it is not optional — it is what an ESA inspector will check against.

The relevant part for EV charging is that a charger is a continuous load, so it counts at 125% of its rating. A 40 amp charger is a 50 amp demand. A 48 amp charger is a 60 amp demand.

Now put that against a 100 amp service that already has:

LoadDemand contribution
First 90 m² of living area5,000 W
Each additional 90 m²1,000 W each
Electric range6,000 W typically
Electric water heaterFull rating
Electric dryerFull rating
Central air conditioningLarger of AC or heat, not both
EV charger at 40 A12,000 W (at 125%)

Convert to amps at 240 V and it becomes obvious quickly. A house with gas heat, a gas range, a gas dryer and gas water heating has a lot of room. A house with electric water heating, an electric range and central air does not.

This is the whole answer, and it is why “can I charge on 100 amps” has no general answer — it depends on what else is electric in your house.

The three honest options

1. It already works

Run the calculation, it passes, install the charger. Common in Barrie houses with gas heating and gas hot water — which is most of the housing stock served by Enbridge in the city, though notably not many rural properties in Oro-Medonte and Springwater where propane and electric water heating are more common.

Cost: $900–$1,800 for a typical attached-garage install.

2. Load management

An energy management system monitors the total draw on the service and throttles or interrupts the charger when the rest of the house needs the capacity. Under CEC Rule 8-500 this permits a Level 2 charger on a service that would otherwise fail the calculation.

This is the option most people are not offered and it is usually the right one.

Cost: $550–$800 for the device and setup, on top of the install.

The practical experience: on the handful of evenings a year when you run the oven, the dryer and the air conditioning simultaneously, your car charges slightly slower. You are asleep. You will not notice.

3. Service upgrade to 200 amps

The real answer when the house has genuinely outgrown its service — electric heat, a heat pump without gas backup, a planned second charger, a basement apartment, a hot tub, a workshop.

Cost: $2,200–$3,800 in Barrie depending on overhead or underground service. See our panel upgrade cost guide for what drives the range.

The dishonest fourth option

Install the charger anyway on the assumption that you will never run everything at once.

We get called to fix the results of this. It is not a code position, it will not pass inspection if it is inspected, and if the work was never notified to ESA, it is undocumented work sitting on an overloaded service. The immediate symptom is a main breaker that trips on cold January evenings. The insurance conversation after an electrical fire is worse.

If a quote for a charger on a 100 amp service does not mention either a load calculation or a load management device, ask why not before you accept it.

Hardwired or plug-in

Hardwired is what we recommend. The charger is permanently connected, there is no receptacle to fail, and it is the cleaner installation.

NEMA 14-50 receptacle is legitimate and has one real advantage: you can take the charger with you when you move. Two conditions. It must be on a GFCI breaker under current code. And the receptacle must be an industrial-grade unit — Hubbell, Bryant, or equivalent. The receptacles that melt under sustained 40 amp load are almost invariably $12 big-box units, and they melt because a 40 amp continuous load is genuinely demanding on a connection designed for occasional RV use.

If someone quotes a plug-in install, ask which receptacle they are fitting.

What it costs in Barrie

ScenarioTypical cost
Attached garage, panel in basement below, short run$900–$1,300
Attached garage, long run or finished basement to fish$1,300–$1,800
Detached garage, trenched underground feed$2,200–$4,000
Add: load management device and setup$550–$800
Add: 200 A service upgrade if genuinely required$2,200–$3,800
ESA permitIncluded

A note on the detached garage: in Barrie that is a seasonal job. Trenching frozen clay in February is not something we quote, and the frost here goes to about 1.2 metres. Plan detached-garage runs for May through October.

On rebates

Federal and provincial EV charger incentive programs change frequently and several Ontario-facing ones have closed or been restructured. We do not quote net-of-rebate prices, because a quote that depends on a program neither of us controls is not a quote.

Check what is currently available yourself before you commit, and treat any rebate as a refund arriving later rather than a discount on the invoice. If a contractor’s price only makes sense with a rebate attached, ask what happens if the program has closed by the time you apply.

What about Level 1?

Worth mentioning because it gets dismissed too fast. A standard 120 V outlet adds roughly 8 km of range per hour — about 80 to 100 km over an overnight charge.

For a plug-in hybrid, or a commute under 60 km a day, that is genuinely sufficient and it costs nothing. The one requirement is that it must be a dedicated circuit. Sharing it with the chest freezer and the workshop outlet is how people spend a winter resetting a breaker.

If you are unsure whether you need Level 2, try Level 1 on a dedicated circuit for a month first. It costs $300 to have one run and it answers the question with your actual driving rather than a spreadsheet.

FAQ

Related questions

Can I install a Level 2 EV charger on a 100 amp panel?

Often yes, using a load management device that throttles the charger when the rest of the house needs capacity. Sometimes yes without one, if the house has gas heat, a gas range and a gas dryer. The Section 8 calculation decides it, and it should be run before anyone quotes.

Is load management cheaper than a service upgrade?

Substantially. A load management device is $550 to $800 installed in Barrie; a 200 amp service upgrade is $2,200 to $3,800. Since your car charges overnight either way, the device is usually the better answer.

Does an EV charger need a permit in Ontario?

Yes. Adding a dedicated 240V circuit requires notification to the Electrical Safety Authority and an inspection. It is a modest cost and it is what makes the installation visible to your insurer.

What happens if an electrician installs a charger without the calculation?

It will not pass inspection if it is inspected, and if it was never notified it is undocumented work on an overloaded service. The practical risk is nuisance tripping of the main breaker, and the insurance risk after a fire is worse.

Talk to a Barrie electrician

Describe the problem over the phone. We can usually tell you whether it needs a truck today or can wait for a scheduled visit — and roughly what it costs — before anyone books anything.

(705) 555-0147

Mon–Sat 7am–7pm · 24/7 emergency callout

(705) 555-0147 Same-day callback before 4pm