Solar battery storage and home battery backup in Ottawa

Lithium ion batteries have proven to be an extremely useful part of solar energy projects: they let you store extra solar energy, which can then be used on gloomy days and whenever backup power is needed. At KAJK Constructors, we help you benefit from this solar energy storage. From the product selection to installation and more, we'll be by your side.

One of the main concerns we hear about solar energy is the lack of sufficient sunlight, on a rainy day for example. With a lithium battery installed, all of those concerns wash away. Why lithium batteries are a great fit for solar projects:

A grid-tied solar system has to stay synchronized with the grid to run. When Hydro Ottawa's supply drops, the panels stop feeding your home. CanREA's 2024 Go Solar Guide says the panels “will not power the home during a power outage unless there is energy storage attached.” The shutdown is deliberate: ESA warns that power fed back into a dead line can put utility crews “in serious jeopardy.”

A battery built for backup changes that. When the grid fails, the system disconnects from the street and runs the circuits it was designed to carry from stored energy, recharged by the panels whenever the sun is up. On normal days it carries surplus solar into the evening and through a run of grey weather.

How long it lasts depends on capacity and on what you ask it to run. Hydro Ottawa's battery storage page says the right size depends on your energy use and how much backup you need. For scale, the Home Renovation Savings program's contractor checklist (October 2025) describes a typical home project as 5 to 10 kW of solar with a 13.5 kWh battery.

It pays off when at least one of three things is true: you need power during outages, you are on a rate plan with an expensive peak, or the rebate path suits your house. The second is easy to check. These are the Ontario Energy Board's prices, set for November 1, 2025 and still the current table when we read it on 2026-10-01. The OEB resets them every November 1.

On Ultra-Low Overnight, the weekday 4 p.m. to 9 p.m. price is ten times the overnight price. Every kilowatt-hour your battery supplies in that window is one you do not buy at 39.1 cents. On Time-of-Use the gap is about two to one, so there the savings case is thinner and backup does more of the work.

Ontario's Home Renovation Savings program, run by Enbridge Gas and Save on Energy, pays $300 per kWh of battery, up to half the battery's cost and no more than $5,000. Panels earn a separate rebate of $1,000 per kW, also capped at $5,000. We read those terms on homerenovationsavings.ca on 2026-10-01. The catch is in the program's own words: anyone who takes the incentive is “not eligible to participate in a net-metering agreement” with their utility.

Most of what turns up under “battery storage negatives” concerns the grid-scale projects proposed around Ottawa. For a battery at a home or a business, these are the trade-offs:

We stay with the project from product selection to installation. On a home system with a battery, the order of work looks like this:

We size lithium storage for large commercial and industrial buildings as well as homes. Above 12 kW AC, Hydro Ottawa requires a Connection Impact Assessment stamped by an Ontario professional engineer, and its faster simplified assessment excludes any project with batteries. The standard fee for a generator up to 500 kW was $1,130 when we read it on 2026-10-01. Our commercial and industrial solar page covers the incentives a business can use.

Storage also pairs with charging. ESA Bulletin 86-1-7 notes that many smart chargers let you choose whether the car charges from the grid, the panels or the battery, which matters if you plan an EV charger after the panels. For a house, start with residential solar, and see the full list of current energy incentives before you decide.