Start with the same scope
Check the panel model and quantity, inverter arrangement, mounting, electrical work and monitoring. A proposal should distinguish the array’s rated capacity from an estimate of electricity produced over time.
Then look for enabling work. Roofing, structural investigation, trenching or service changes may be included, provisional or excluded. The difference matters to the total project cost.
- Exact equipment and quantities
- Scope of installation and electrical work
- Assumptions about the existing building
- Itemised exclusions and provisional allowances
Ask where the forecast comes from
A production forecast should identify the site assumptions and the method behind the estimate. National resource maps can support an early conversation, but they do not inspect a particular roof.
Ask what the financial model assumes about electricity use, rates, operating costs and future performance. A central estimate should be presented as an estimate, not a contractually guaranteed outcome.
Understand the utility arrangement
Connection and billing arrangements need to be confirmed with the relevant utility. In Ontario, the OEB describes net metering as using renewable electricity on site and receiving bill credits for eligible exports.
Those Ontario credits offset electricity-consumption charges, not every line on the bill, and unused credits cannot be carried forward indefinitely. The OEB states a maximum 12-month carry-over. Other provinces have their own arrangements.
Read the responsibility column
Who makes the applications? Who pays the identified fees? What happens if a required approval changes the design? Those responsibilities should be clear before the project moves forward.
Compare equipment warranties, workmanship terms and ongoing support separately. Ask what happens if a product issue requires diagnosis, shipping, labour or removal and reinstallation.
Pause before signing
Verify the legal name of the contracting party, the qualifications needed for the work and the applicable insurance. Read payment milestones, cancellation terms and the process for changes to the scope.
If financing, leasing or a power-purchase arrangement is involved, review it as its own agreement. Do not assume a low monthly figure means a lower total cost.
- Can I explain what I am buying?
- Can I identify the uncertain inputs?
- Do I know what could add cost?
- Do I know who is responsible after handover?
Questions, answered.
Is the cheapest price per watt always the best value?
No. That comparison can omit differences in equipment, included work, site complexity, warranty terms and support. Compare a consistent scope first.
Should incentives be treated as confirmed savings?
Only after current eligibility, application requirements and approval have been established. A proposal should not quietly subtract an unapproved incentive from the amount you may need to pay.
Where should I verify Ontario net-metering rules?
Start with the Ontario Energy Board’s net-metering guidance and your electricity utility. Confirm eligibility and connection feasibility before investing in a system.
Further reading
For primary guidance, see Natural Resources Canada: solar energy and Ontario Energy Board: net metering. Ontario-specific rules do not apply across every province. Confirm the current requirements with your utility.