The ten month credit window, and why it changes sizing
Oshawa Power's Conditions of Service zeroes generation credits carried for the previous ten consecutive months. That is a shorter window than the province permits and shorter than the neighbouring Durham distributors run, and it is the most consequential local fact on this page. The whole logic of net metering is that a summer surplus pays for a winter deficit, and a shorter carry period gives that surplus less time to find a matching bill.
The practical effect is on sizing rather than on whether solar works. In Oshawa, be more careful about oversizing than you would be a few kilometres west. An array matched to your actual annual consumption behaves the same here as anywhere. An array built to fill the roof, generating well beyond what the household uses, produces credits that are more likely to expire before you draw them down. Ontario also pays no cash for annual net excess generation, so an expired credit is simply gone rather than converted into money.
That also shifts the value of storage. Because Oshawa Power bills on time-of-use, electricity you consume in the house while the array is producing, or that a battery holds for you until an expensive hour, is worth more than an export credit you may not spend inside the window. In most Ontario cities storage is a preference. Here the arithmetic behind it is a little stronger.
One line item does not move whatever you generate: the monthly fixed charge, published at $29.79. Solar offsets the energy you would otherwise buy, not a fixed distribution charge, so a bill gets smaller rather than disappearing. That figure comes from a rate sheet the utility was still serving as current but which carries an effective date of January 1, 2025, so check it against your own bill before you build a projection on it.
Connecting to Oshawa Power, step by step
Oshawa's distributor is Oshawa Power, licensed by the Ontario Energy Board as Oshawa PUC Networks Inc. and based at 100 Simcoe St. South. An array of 12 kW or less is treated as a Micro-Embedded Generation Facility, which is the category almost every residential rooftop system falls into.
The process starts with an email rather than a form. You send a Preliminary Consultation Information Request to GenerationConnections@oshawapower.ca, Oshawa Power runs a capacity check, and only then do you file the Micro-Embedded Generation Connection Application, known as Form C, with manufacturer specifications for both the generation source and the inverter. Have those specifications settled with your installer before filing, because a form submitted with placeholder equipment is a form that gets amended.
No Connection Impact Assessment is required at this size, and that is the main reason the 12 kW ceiling is worth designing to. Above it the study requirements change and so does the timeline. Once the application clears, Oshawa Power issues an Offer to Connect and a connection agreement, then installs a bi-directional meter once you supply an Electrical Safety Authority Connection Authorization.
Budget the connection as starting at $550 plus HST rather than as a fixed total. That figure is a floor: it excludes the bi-directional meter, which is a separate cost. Ask Oshawa Power for the all-in number for your specific service before you treat the connection as a rounding error in the project budget.
The Renewable Energy Approvals Checklist, and the heritage register
Oshawa publishes a Renewable Energy Approvals Checklist that answers the permit question directly, which is more than most Ontario cities do. Building-mounted solar photovoltaic needs a City building permit but no provincial Renewable Energy Approval. Free-standing PV of 12 kW needs neither. Free-standing PV above 12 kW needs an REA. The City's own portal lists Renewable Energy as its own permit type for solar panels, so you are not filing under a generic category.
A roof-mounted submission includes the application form, Schedule 1 for BCIN designers, fees, a site plan, plans showing the placement of the facility, and structural roof plans detailing its connections to the building. The structural roof plans are the line homeowners under-budget for. They are drawings of how the array attaches to the structure, produced by someone qualified to draw them, and they are not something an installer conjures on the day of submission. Ask early whether they sit inside the quoted price.
The checklist itself carries an older revision date than the rest of the City's building guidance while still being served as current. It accurately describes what Oshawa publishes today, but if your project is unusual it is worth a call to confirm nothing has shifted underneath it.
Ontario has no US-style homeowner associations, and Oshawa's heritage controls are narrow. The City keeps a municipal register under the Ontario Heritage Act covering properties designated individually under Part IV, properties inside a Heritage Conservation District under Part V, and non-designated properties listed under Section 27. Oshawa has exactly one Heritage Conservation District, in the core area of the South Field at the Oshawa Executive Airport. For virtually every homeowner, then, the only heritage question is whether their own property appears on the register, which is a single check rather than a process.
What an Oshawa roof produces in a year
Natural Resources Canada's municipal photovoltaic potential dataset puts Oshawa at about 1,167 kWh a year for each kW of installed capacity. A 7 kW array models at roughly 8,200 kWh a year on that basis, and a 12 kW array, the top of the micro-generation category, at roughly 14,000 kWh. Those numbers describe a well oriented, unshaded roof, so a site assessment will usually come back somewhat lower.
Production is strongly seasonal in this part of Ontario, with long summer days producing several times what short, overcast winter ones do, and snow cover flattening output for stretches. That is normal and the credit mechanism is built for it, but in Oshawa the shorter carry window means the summer surplus has less runway, which is a reason to look closely at the shape of your consumption rather than only its annual total. A household that heats with electricity has a different answer here than one that heats with gas.
Before a design is drawn, check the age of the roof covering. Modules are warranted for decades and are awkward to remove and refit, so if the shingles are close to replacement it is cheaper to do that first. It is also the cheapest moment to sort out any structural questions the roof plans will raise.
Oshawa has the most mixed housing stock in Durham's lakeshore
Per Statistics Canada's 2021 structural type data, single-detached houses are still the largest single group in Oshawa at about 55.5% of dwellings, but the balance is spread more widely than in the towns to the west. High-rise apartments are about 11.4% and low-rise buildings under five storeys about 9.7%, so more than a fifth of Oshawa dwellings sit in a building where the roof is not the resident's to decide about.
That matters more than the headline number suggests. If you live in an apartment, the useful first question is not which panels to buy but whether the building owner or condominium corporation will entertain a rooftop project at all. It is a five minute question that saves weeks, and the answer is often shaped by the building's own roof replacement schedule.
Row houses are about 9.7% of dwellings and often share a roofline with neighbours, which narrows the usable south-facing area. Semi-detached homes, about 8%, and duplexes, about 5.5%, usually still allow an individual install but share a structure with a neighbour, so the mounting layout needs to respect where one property ends and the next begins.
Rebates worth checking before you finalise a design
Ontario's Home Renovation Savings Program offers combined rebates of up to $10,000 for solar PV paired with battery storage. It launched in January 2025 and was expanded for the 2026-27 programme year, which runs April 1, 2026 to March 31, 2027. The battery pairing is a better fit in Oshawa than in many Ontario cities, for the reason set out above: with a shorter credit carry window and time-of-use pricing, electricity stored and used at home holds its value more reliably than a credit waiting for a bill to land against.
Read the fine print on configuration before you apply. Homeowners taking the HRSP solar incentive are generally directed to a load-displacement configuration rather than full net metering, which is a design decision, not a paperwork one, and it interacts directly with the Form C application you file with Oshawa Power. Confirm the current rules with your installer before either application goes in.
Federally, 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 Canada Greener Homes Affordability Program replaced it in September 2025, providing no-cost retrofits through participating provinces, which do not currently include Ontario, for low- to median-income households, with solar PV federally eligible but each province setting its own technology list. Canada has no federal investment tax credit for residential solar comparable to the United States one, so discount any quote that assumes one. Beyond that, ask whether any municipal or utility financing, such as a local improvement charge arrangement, is currently open in your area.