Understand your home’s electrical capacity
Electrifying your home doesn’t always require a service upgrade
Planning to add new electrical load to your home? Whether you’re fuel switching or planning other installations that will rely on electric power – these projects will increase your home’s electricity needs. Common installations include:
- Installing a heat pump or a Level 2 electric vehicle (EV) charger.
- Adding a pool or hot tub.
- Home expansions or additions of a suite.
Homeowners often wonder if their home’s electrical panel will be able to support it – and the costs associated with upgrading it. The overview below provides guidance for load calculations and alternatives to service upgrades, which often aren’t required.
Two ways to calculate a home’s capacity
To prepare for installation, your electrical contractor will have to do a load calculation to make sure your home has enough electrical capacity. It’s also required for the electrical permit.
There are two common ways that your electrical contractor could calculate your home’s electrical capacity. For the most accurate results, we recommend the meter data method.
With the traditional – calculated load – method, the electrical contractor will use a standardized calculation which uses the square footage and estimated usage figures for all appliances in the home based on proxy data.
It relies on industry averages to estimate how much electricity your home uses, and how much it might be using at any one time, which is then compared to the capacity of your current electrical service.
Using your meter data creates a more accurate calculation. With this method, your electrical contractor will review your actual usage over a 12-month period.
This method has been approved by Technical Safety BC since 2023, but not all contractors are using it yet. This method provides an accurate number for the most important data point, your maximum demand load (the highest amount of electricity you use at once), as well as your consumption patterns.
Given that it requires 12 months of meter data for your account, this method isn’t available for new construction or if you’ve moved in the last 12 months. In those scenarios, your contractor should use the traditional method.
Download your meter data
Your electrical contractor can’t access your meter data, so you’ll need to download it for them. Here’s how:
- Log in to MyHydro. If you don’t have a MyHydro profile yet, create one first.
- Go to the data export centre.
- Select the export type: consumption history.
- Set the date range for the last 12 months.
- Change the interval to hourly.
- Select Export data.
Your data should be ready within 24 hours. You’ll receive an email when it’s ready, and you can then download the file.
Using the data
After you share your meter data with your electrical contractor, they can:
- Use the approved formula from Technical Safety BC or the local municipality to convert your peak kilowatt-hour (kWh) usage to amps.
- Then, they’ll essentially subtract that from your service size (e.g. 100 amp) to calculate the remaining capacity.
The results may indicate that you have enough available capacity for the new electrical load and don’t need to take any further steps before installing it.
If the results show that you would be nearing or over the capacity of your service, you’ll need to decide what to do next.
Service upgrades and load management alternatives
Your electrical contractor may recommend a service upgrade to accommodate the new electrical load, but this can increase project costs and timelines significantly and may not always be necessary.
Talk to them about alternatives listed below – which optimize your home’s existing capacity – before deciding to upgrade your electrical service.
Load management options
There are energy management technologies available to balance load between your home’s big draws of electricity. They’ll monitor the draw and automatically engage as needed to ensure you don’t exceed your capacity.
| OPTION | BEST FOR |
|---|---|
EV power management device |
|
Power management device |
|
| OPTION | BEST FOR |
|---|---|
| Removal of unneeded electrical load from the panel |
|
Energy efficiency renovations |
|
Energy efficient equipment replacements |
|
Follow energy efficiency tips to reduce your usage |
|
Upgrade your service panel
If you need to upgrade your service, it’s essential to avoid oversizing your system unnecessarily, as this can lead to higher costs for installation and equipment.
Recommendations to avoid oversizing your electrical service:
- Get a professional load calculation done by an electrician, using the meter data method (outlined above) if it’s available to you. This will assess your current electrical service and should also consider any upcoming projects that might increase your electrical demand (e.g., installing an EV charger, heat pump, or home expansion).
- Based on the results of the load calculation, discuss with your electrician whether upgrading from 100 amps to 200 amps is sufficient, for example, rather than to 320 or 400 amps.
- Before upsizing your service, explore energy efficiency options like switching to LED lighting, replacing inefficient appliances, and adding home energy management systems. These provide long-term savings and reduce energy waste.
More about service upgrades: