Systems
Backup Power for a BC Home: Standby Generator vs Home Battery
When the power goes out on a wet BC winter night, what keeps your heat, your fridge, and your sump pump running? A standby generator and a home battery solve it in different ways, and both have to be planned at electrical rough-in.
Every winter, one wet, windy night takes out the power somewhere in the Lower Mainland or the Fraser Valley for hours, sometimes for a couple of days. A tree comes down on a line, and a whole neighbourhood goes dark. For most homes that means a cold night and a fridge you are afraid to open. For a home on a well and a sump pump, it can mean a lot worse.
The question we get after every one of those storms is the same. How do I make sure my heat, my fridge, and my basement pump keep running when the grid drops. There are two real answers, and they work in very different ways.
One is a standby generator that switches on by itself and runs on fuel. The other is a home battery that stores electricity and quietly powers the house until it runs low. Choosing between them is not really about the device. It is about how your power fails, what you need to keep on, and, most of all, planning the wiring before the walls close.
The two ways to keep the lights on
A standby generator is a fixed unit that sits outside the house, usually on a small pad. It runs on natural gas from the utility or on propane from a tank. When the grid goes down, it starts automatically and feeds the house through a transfer switch. As long as the fuel keeps coming, it keeps running, which is its big strength: a natural-gas standby unit can carry a home through a multi-day outage without anyone touching it. The trade-offs are that it makes noise while running, it needs regular servicing like any engine, and it needs a fuel source at the lot.
A home battery is a sealed unit, often wall-mounted, that stores electricity. It charges from the grid when power is normal, or from rooftop solar if the home has it. When the grid drops, it powers the house instantly and silently. The trade-off is time. A battery only runs for as long as its stored charge lasts. Once it drains, it needs the grid to come back or the sun to come up so it can recharge. For short, frequent outages it is close to perfect. For a two-day blackout in December, a single battery will not carry a whole house the whole time on its own.
Neither one is simply better. They solve different problems.
Match the choice to how your power actually fails
The right call comes from looking at your real situation, not a brochure.
How long do your outages last? If you live somewhere that loses power often but only for an hour or two, a battery handles that beautifully and you never hear it. If you are on a rural Fraser Valley lot where a winter storm can take the line down for two or three days, a fuel-burning standby generator is the honest answer, because a battery would drain long before the grid returned.
Do you have gas at the lot? A natural-gas standby generator is simplest where a gas line already serves the home. On an all-electric home with no gas, propane is the fallback for a generator, which means a tank to fill. That tips more of these homes toward a battery, especially if solar is already in the plan.
Are you already planning solar? A battery and rooftop solar work together. Solar recharges the battery during the day so it can carry the home again at night, which stretches a battery through a longer outage in a way it never could on its own. If you are thinking about solar, plan the battery in the same conversation. We cover the wiring side of that in our guide to a solar-ready custom home in BC.
A generator runs long but loud. A battery runs quiet but not forever. The wrong question is which is better. The right one is how your power actually fails, and what you can live without until it comes back.
Icon Projects Team
Decide what actually has to stay on
Here is the decision that saves the most money and the most trouble: you almost never need to back up the whole house.
Powering everything, every outlet, the electric range, the hot tub, the whole cooling system, means a much bigger generator or a bank of batteries. And most of that load is things you can happily do without for a few hours. The smarter approach is a backed-up sub-panel: a separate small panel that carries only the circuits you truly need when the grid is down.
For most BC homes, that essential list looks like:
- The heating system. In an all-electric home this is the heat pump, or at least enough of the mechanical system to keep the house from getting cold. This is the whole point on a winter night, and it ties directly into the loads we plan in our electrical planning guide and the mechanical loads in our heat pump and HRV guide.
- The refrigerator and freezer, so you are not throwing out a week of food.
- The sump pump. On a home with a basement or a high water table, this one can prevent a flood, and a power outage during a storm is exactly when the pump is needed most.
- Well pump, if the home is on a well. No power, no water, so on an acreage this is essential.
- Some lights, key outlets, internet, and a way to charge phones, so the house is livable and you can see what is happening in the area.
We work out this list with each owner at design, then group those circuits together so they land on the backed-up sub-panel. That grouping is a rough-in decision. Once the walls are closed, moving circuits onto a backed-up panel means opening them again.
The transfer switch is the piece that makes it safe
Whatever backup source you choose, it connects to the house through a transfer switch. This is not an optional extra. It is the part that keeps everyone safe.
A transfer switch moves the home between grid power and backup power, and it makes sure the two are never connected at the same time. This matters for a serious reason. If a generator or battery fed power backward onto the utility line during an outage, it could send electricity down a line that crews believe is dead, and that puts the people restoring your power in danger. The transfer switch prevents that. Any code-compliant backup install in BC has one.
An automatic transfer switch senses the outage and does the swap by itself, usually within seconds, then switches back when the grid returns. A manual one is cheaper but needs someone home to flip it. For a standby generator most owners want the automatic version, so the house recovers on its own even when nobody is there.
The transfer switch, the backed-up sub-panel, and the wiring path out to wherever the generator or battery will sit all belong in the electrical rough-in. All electrical work like this is done on a permit through Technical Safety BC and by a licensed electrical contractor. Planning it early is the difference between a clean install and a wall-opening retrofit.
Plan the path even if you are not buying yet
A lot of owners are not ready to commit to a generator or a battery on day one. That is fine. The move that costs almost nothing now and saves a lot later is to rough in the path.
At a minimum, we plan the panel to have room for a future backed-up sub-panel, group the likely essential circuits, and leave a wiring path out to the spot where a generator pad or a battery would go. If a battery is a real possibility, the panel is set up to accept it, since a battery pushes power back into the panel and the panel has to be ready for that, the same as it would be for solar. None of this means buying the equipment now. It means not building a house that fights you when you decide to add backup later.
This is the same principle that runs through every system we plan ahead: the empty conduit, the spare panel space, the wiring path. It is cheap as a line on a drawing and expensive as a renovation. We lay out the broader version in our home-automation wiring guide.
Frequently asked questions
Should I choose a standby generator or a home battery for my BC home? It depends on how your power actually fails. A standby generator runs on natural gas or propane and can carry a home for as long as the fuel holds, which suits long multi-day outages and rural lots. A home battery runs silently and cleanly but only for as long as its stored charge lasts, then it needs the grid or solar to recharge, which suits short, frequent outages and homes that already plan for solar. Icon Projects sizes the choice to your outage history and what you need to keep running, then wires the house so either one drops in cleanly.
What is a transfer switch and why do I need one? A transfer switch is the device that safely moves your home between grid power and backup power. It stops your generator or battery from ever feeding electricity back onto the utility line, which protects crews working to restore the grid and is required. An automatic transfer switch does the swap on its own within seconds of an outage. Icon Projects plans the transfer switch and its dedicated circuits at the electrical rough-in, because retrofitting it into a finished home means opening walls.
Do I have to back up my whole house? No, and usually you should not. Backing up everything means a much larger generator or battery, and most of the load in a home is things you can live without for a few hours. The common approach is a backed-up sub-panel that carries only the essentials: heat, the fridge, some lights, the sump pump, internet, and key outlets. Icon Projects works out that essential list with you at design, so the backed-up circuits are grouped together and sized right.
Can I add backup power after my home is built? You can, but it is cleaner to plan it at rough-in. The transfer switch, the backed-up sub-panel, and the wiring path to where a generator or battery will sit are all easy to run while the walls are open. Adding them later means fishing new circuits and often re-working the panel. Icon Projects at minimum roughs in the path and the panel space so a future generator or battery is a straightforward install, not a renovation.
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