Updated October 2026 · By the Solar Power Store Canada team in Barrie, Ontario
In short: Most battery backup sump pump kits add a second, smaller 12 V pump that only runs when the power is out. For a bigger pump (1/2 HP and up), two pumps, a finished basement or long outages, a better setup is a lithium battery and an inverter that run your main pump itself, at full capacity. Our recommended build is a Luxpower LXP6K 6 kW inverter, a Maple Leaf Beaver Heated 48 V LiFePO4 battery and a Maple Leaf Mountie outdoor battery cabinet, sold together as our Sump Pump Battery Backup Kit for $4,471.99 with one battery or $5,902.99 with two (10% off the regular price of the parts), with an optional solar panel and Goose ground mount package. One battery gives a 1/2 HP pump about 4.7 hours of actual pumping, which covers much longer outages because sump pumps cycle on and off, and you can add batteries for more. Our team in Barrie supports and repairs the equipment we sell, and we can ship to you or directly to the homeowner, or help arrange the installation.
The 4 ways to back up a sump pump
| Option | How it works | Pumping capacity | Main drawbacks | Best for |
|---|---|---|---|---|
| 12 V backup pump + battery | A second DC pump in the pit, run from a 12 V battery and charger | Usually lower than your main pump | Smaller pump; lead-acid batteries need replacing every few years; protects the pit only | Small pumps and light water flow |
| Water-powered backup pump | Uses city water pressure to pull water out of the pit | Depends on your water pressure | Needs municipal water and a backflow preventer; uses a lot of water; will not work on a well; check local plumbing code | Homes on city water with good pressure |
| Inverter + lithium battery | Runs your existing main pump from a battery when the grid fails | Full capacity of your main pump | Higher upfront cost; needs an electrician | Bigger pumps, finished basements, long outages, backing up other essentials too |
| Generator | Portable or standby generator powers the pump circuit | Full capacity | Fuel, noise, maintenance; a portable unit needs someone home to start it | Whole-home backup. See our backup and standby generators |
Why a lithium battery and inverter is better for big sump pumps
- Your main pump keeps working at full capacity. There is no smaller second pump to fall behind during a heavy storm.
- Long-life LiFePO4 battery. The Beaver Heated is rated for 6,000+ cycles, with no topping up, no fumes and no yearly replacement.
- Cold-weather ready. The batteries sit outdoors in the insulated Mountie cabinet, rated down to -40°C, and the Beaver Heated battery's built-in heater works from -25°C.
- Backs up more than the pit. The same system can keep the fridge, furnace fan and internet running.
- Grows with you. Add batteries for longer runtime, or solar panels later. The LXP6K accepts up to 8,000 W of solar input.
Our recommended setup: Luxpower + Beaver Heated + Mountie
| Part | What it does | Price (CAD) |
|---|---|---|
| Luxpower LXP6K 6 kW split-phase inverter | Powers your pump circuit from the battery and recharges it from the grid (or solar) | $1,999 |
| Maple Leaf Beaver Heated 48 V 100 Ah LiFePO4 | 5.12 kWh battery (4.92 kWh usable) with built-in heater, UL9540A certified | $1,500 each |
| Maple Leaf Mountie battery cabinet | Insulated, IP65 waterproof outdoor cabinet for up to six Beavers; protects them down to -40°C | $1,379.99 |
| Beaver 2 AWG battery cable kit | Battery cables and grounding | $89.99 per battery |
That comes to $4,968.98 with one battery, or $6,558.97 with two. Our Sump Pump Battery Backup Kit bundles all four parts for 10% less, $4,471.99 or $5,902.99, and you can add four or eight 550W+ solar panels on a Maple Leaf Goose ground mount to recharge during long outages. For two pumps, a large pump plus your fridge and furnace, or the longest outages, step up to the Luxpower SNA 12K + 4 Beaver + Mountie kit: a 12 kW inverter and 20.48 kWh of storage for $12,199.99. Like all the systems we sell, it is supported and repaired by our team in Barrie, Ontario.
How long will a battery run my sump pump?
Hours of pumping = usable battery kWh × 1,000 ÷ your pump's running watts. Typical running watts from utility generator-sizing charts are about 800 W for a 1/3 HP sump pump and 1,050 W for a 1/2 HP pump. For larger pumps, check the nameplate (volts × amps).
| Pump (running watts) | 1 Beaver (4.92 kWh) | 2 Beavers (9.84 kWh) | 4 Beavers (19.68 kWh) |
|---|---|---|---|
| Typical 1/3 HP (800 W) | 6.2 hours | 12.3 hours | 24.6 hours |
| Typical 1/2 HP (1,050 W) | 4.7 hours | 9.4 hours | 18.7 hours |
| Larger pump (1,500 W) | 3.3 hours | 6.6 hours | 13.1 hours |
These are hours of actual pumping. A sump pump runs in cycles, so the battery lasts much longer in real life: a 1/2 HP pump that runs 15 minutes an hour uses about 0.26 kWh an hour, so one Beaver covers roughly 18 hours of storm, less the inverter's own standby use.
Sizing the inverter for a big pump
Pump motors draw a surge when they start, often about twice their running watts (around 2,150 W for a typical 1/2 HP pump). The 6 kW LXP6K has plenty of room for one pump of that size plus a few essentials. If you have two large pumps or want to add a well pump or other motor loads, choose the 12 kW SNA 12K. Either way, have a licensed electrician check your pump's nameplate and starting current before you buy.
Installation tips
- Put the pump on its own backed-up circuit. The inverter feeds the pump circuit, running it from the grid normally and switching to battery when the power goes out.
- Mount the inverter indoors, above the flood line. The LXP6K is an indoor unit rated for 0°C to 50°C.
- Put the batteries outdoors in the Mountie. In Canada, battery storage like this can't be installed in a basement. The insulated IP65 steel cabinet protects them outdoors down to -40°C.
- Keep a high-water alarm in the pit and test the system every few months by switching off the inverter's grid supply breaker.
- Get a permit. Connecting an inverter to your home's wiring needs an electrical permit and inspection (ESA in Ontario). We ship to you or directly to the homeowner for your own licensed electrician, or we can help arrange the installation.
Grow it into home battery backup
The same batteries and inverter are the start of a home backup system: add Beavers for longer runtime, add solar panels to recharge during long outages, or move up to a whole-home system. See our Home Battery Backup Systems and our guide to Tesla Powerwall alternatives in Canada.
Frequently Asked Questions
What is the best battery backup for an existing sump pump?
For small pumps and light inflow, a 12 V backup pump kit is the simplest. For 1/2 HP and larger pumps, or when you also want the fridge and furnace on backup, a lithium battery and inverter that run your main pump is the better choice. Our recommended build is the Sump Pump Battery Backup Kit: a Luxpower LXP6K, a Beaver Heated battery and a Mountie cabinet for $4,471.99.
How long will a battery backup sump pump run?
One 4.92 kWh Beaver battery runs a typical 1/2 HP (1,050 W) pump for about 4.7 hours of actual pumping, which usually stretches across 18 hours or more of a storm because the pump cycles on and off. Two batteries double that, and four quadruple it.
Can I use a deep cycle battery for a sump pump?
Yes, 12 V backup pump kits use deep cycle batteries, usually lead-acid, which need replacing every few years. A 48 V LiFePO4 battery with an inverter lasts far longer (the Beaver Heated is rated for 6,000+ cycles) and runs your main pump instead of a smaller backup pump.
Does a battery backup work in a Canadian winter?
Yes. The batteries go outdoors in the insulated Mountie cabinet, which protects them down to -40°C, and the Beaver Heated battery's built-in heater works from -25°C so it can charge in the cold.
Can I put the batteries in my basement?
No. In Canada, battery storage like this can't be installed in a basement. That's why our kit includes the Mountie, an insulated, waterproof cabinet that sits outside. The inverter mounts indoors, on a wall near your electrical panel and above any flood level.
Do I need an electrician?
Yes. Connecting an inverter to your home's wiring needs a licensed electrician, an electrical permit and an inspection (ESA in Ontario). We can help arrange the installation.
Is a water-powered backup sump pump a better option?
It can be if you are on city water with good pressure, since it needs no battery. It uses a lot of water, needs a backflow preventer, will not work on a well, and is not allowed everywhere, so check your local plumbing code.
Will the same system run my fridge and furnace?
Yes, if you size it for them. Add their running watts to your pump's, and add batteries to keep the same runtime. Send us your pump's nameplate and what else you want to back up, and we will size it for you.
Who supports and repairs the system?
We do. Our team in Barrie, Ontario supports and repairs the Luxpower and Maple Leaf equipment we sell. Call 1-888-421-5354 or email hello@solarpowerstore.ca.