Yes, a 100A service may support an EV charger, but the service rating alone is not enough to confirm it. Your existing electrical demand, proposed charging load and equipment determine the appropriate design. A service upgrade is one option; suitable charging settings or an EV energy management system may provide another.
For Toronto and GTA homeowners, the first step is an assessment before purchasing charging equipment. That lets us compare options around your home and driving needs.
Why an empty breaker space is not the answer
Panel space and service capacity are different considerations. A panel can have room for another breaker while the electrical demand still needs attention. Conversely, a shortage of breaker positions does not by itself tell us the home requires a larger service.
We review the installed equipment and proposed loads, including cooking, heating, air conditioning, water heating and other significant appliances. Planned additions belong in the discussion too. A charging design based on today’s equipment should account for a renovation already being planned.
Option 1: A charging rate suited to the available capacity
You may not need the highest output available from a charger. The vehicle’s AC charging capability, daily driving and time parked at home help determine a practical target.
Where the assessment and equipment permit, a properly designed installation at an appropriate charging rate may fit the existing service. Any adjustable settings used in the electrical design must meet the applicable requirements; we do not rely on a casual app change that can be reversed without considering the installation.
Option 2: EV energy management
An EV energy management system, often called EVEMS, monitors electrical demand and controls charging so the installation operates within its designed limits. Depending on the equipment, charging may pause or its power may be adjusted when household demand increases.
ESA recognizes energy management as part of EV charging design under the Ontario Electrical Safety Code. It is not a shortcut around assessment, equipment approval or correct installation. The selected arrangement needs to suit the service, charger and applicable requirements.
Ask how the system resumes charging, what occurs if communication is lost and whether it supports your future plans. Different products have different operating behaviours.
Option 3: Increase the service capacity
A service upgrade may be appropriate when the wider electrical plan needs more capacity or the charging alternatives do not meet your requirements. Consider the complete project if you are also adding electric heating, a second vehicle or substantial renovation loads.
An upgrade involves the customer-side electrical installation and the utility’s connection requirements. Keeping a 100A service with load management and increasing it to 200A are different scopes, so compare complete proposals.
| Approach | Question to resolve |
|---|---|
| Suitable charging rate | Does the permitted installation provide enough charging for your routine? |
| EVEMS | Does the equipment’s control behaviour fit your household demand and vehicle use? |
| Service upgrade | Does the overall electrical plan justify greater capacity and the associated utility work? |
A schedule is different from capacity management
Scheduling charging overnight can be convenient, but a timer alone should not be assumed to provide the same capacity-management function as a designed EVEMS. Other loads can operate overnight, and household routines can change.
Tell us your usual charging hours so they can inform the recommendation. We still establish an electrical design that meets the applicable requirements.
What to share before we quote
- Your address, vehicle make, model and year.
- Typical daily driving and overnight parking time.
- Charger model, if selected, and any plans for a second EV.
- Photos of the closed panel and proposed charging location.
- Existing major appliances and planned electrical additions.
The quote should distinguish wiring, charger supply, EVEMS, any panel work and utility costs. An EV charger installation requires an ESA notification before work starts. Electric FX handles the notification for our work and provides acceptance documentation once the installation is accepted.
Learn about our EV charging and load-management installations and service upgrade options, or request an assessment.
Further reading: ESA EV charging systems bulletin; ESA homeowner charging guidance; Alectra homeowner charging guide.