What an Ottawa system produces in a year
The figure to start from is about 1,200 kWh a year for every kilowatt of panel capacity installed in Ottawa. Scale it to whatever size gets proposed: on that basis a 6 kW array sits near 7,200 kWh a year and a 9 kW array near 10,800, before you subtract for shading, for roof planes that face away from south, and for the winter weeks when panels are under snow. Those subtractions are why two houses on the same street can be quoted very different production from identical hardware, and why a number produced without a site visit is a guess.
System size has a practical ceiling as well as a physical one. Hydro Ottawa handles micro-generation for systems of 12 kW or less, and nearly every residential project fits inside that band. Within it, the sensible limit is your own consumption rather than your roof area, because Ontario credits exports instead of buying them. Panels that produce more than your household uses across a year mostly earn credit you will never spend.
Connecting to Hydro Ottawa, and how long it takes
Hydro Ottawa credits micro-generation customers, meaning systems of 12 kW or less, for excess electricity sent to the grid, and it arrives as an on-bill credit rather than a payment. The process starts with a Service Request that selects net metering. Hydro Ottawa responds in 15 to 60 days with a Service Layout, and that layout is valid for 90 days, so the gap between approval and installation is a real constraint worth scheduling around rather than discovering late.
Electrical Safety Authority Connection Authorization is required before Hydro Ottawa will energize the system. That makes the electrical inspection a gate rather than a formality at the end of the job: without the authorization the array does not go live, however finished it looks from the street. Ask your installer where ESA sits in their schedule, not just whether they handle it.
The fees attached to micro-generation are small but easy to misread on a bill. There is a $10 account setup charge, a small daily service charge, and an offsetting daily rate-rider credit applied against that charge. Ask to see those lines identified on a sample bill so you know what you are actually paying to stay connected as a generator.
What your exported kilowatt hours are worth
Ontario net metering credits exported solar kilowatt hour for kilowatt hour at the retail electricity rate, applied against future bills. Unused credits carry forward for up to 12 months and then expire, and there is no cash payment for net annual excess. In practice you are banking summer production against winter consumption, and the bank has a time limit.
That structure is why sizing is a consumption question. A year of your own bills tells you how much you draw and when, and a system built to that is worth more than a larger one built to fill the roof. Ontario's residential pricing is time-of-use, which makes using your own generation as it is produced more valuable than exporting it and pulling it back later, and it is the main reason storage comes up in these conversations at all.
Ottawa's permit rule and the engineer requirement
Ottawa requires a building permit for any solar collector, photovoltaic or thermal, with a face area of five square metres or more. A residential array of any meaningful size clears that threshold comfortably, so plan on a permit being part of your project rather than an exception you might dodge.
The city also requires that a professional engineer licensed in Ontario design the system and review the installation. The one route around the permit is narrow: a flush mounted array where an engineer has already assessed the existing roof as structurally sound. Both paths put an engineer in the loop, so when you compare quotes, check that the engineering work is priced in rather than added later as a change.
The city's stated first-review turnaround is about five business days for residential buildings, which is quick by Ontario standards, though a first review is not a final approval if comments come back and drawings have to be revised. The ESA electrical inspection is separate from the municipal permit and, as above, controls when the system can be energized.
What Ottawa's housing mix means for your roof
Ottawa's occupied private dwellings, per the 2021 census, are led by single-detached houses at about 42%, followed by row houses at about 21%, apartments in buildings of five or more storeys at about 19%, low-rise apartment buildings under five storeys at about 11%, and semi-detached houses at about 5%. Most homes here therefore have a private roof to work with, which is not true of every Canadian city this size.
The mix matters more than the total. A single-detached house generally gives an installer a full, unobstructed roof to design around. A row house often has a narrow and sometimes shaded south-facing face, which caps usable panel area and can make a smaller array the only honest proposal. Semi-detached homes usually still allow an individual install but share a party wall and roofline with the neighbour, which is worth flagging early. Apartment dwellers, in either tall or low-rise buildings, need landlord or condo corporation approval rather than a homeowner permit, and that is a different conversation entirely.
Rebates and financing an Ottawa homeowner can use
One recent rule change lines up neatly with Hydro Ottawa's micro-generation band. As of May 1, 2026 the Ontario Energy Board raised the simplified micro-embedded generation threshold from 10 kW to 12 kW, so more residential systems now qualify for the streamlined connection process, which is the same 12 kW ceiling Hydro Ottawa uses for micro-generation customers.
The main provincial money is Ontario's Home Renovation Savings Program, launched in January 2025 and running its 2026-27 program year from April 1, 2026 to March 31, 2027, with combined rebates of up to $10,000 for solar PV paired with battery storage. Read the condition before the number: homeowners taking the HRSP solar incentive are generally directed to a load-displacement configuration rather than full net metering, so confirm the current rules with your installer before applying, because it can change how your exports are treated.
Federal help is thinner than it was. The Canada Greener Homes Loan, interest-free up to $40,000, stopped accepting new applications on October 2, 2025, and only previously approved loans are still being funded. The replacement, the Canada Greener Homes Affordability Program, launched in September 2025 and delivers no-cost retrofits through participating provinces, which do not currently include Ontario, for low to median income households; solar is federally eligible but each province sets its own technology list. Canada has no federal investment tax credit for residential solar, so nothing comes back at tax time on that basis.