Buying solar panels for your home: what to check

What should you know about your home before asking for quotes?

Gather 12 months of electricity bills. The kilowatt-hour total shows how much a system should produce, and the pattern shows when you use it. Note any changes you expect, such as an electric vehicle, a heat pump or a home addition, since they raise consumption. Then look at the roof: its age, its pitch, which way it faces and what shades it. A roof that needs replacing in a few years is best fixed before panels go on it.

Ask each installer to use the same inputs so that quotes compare fairly. Our guide on how many solar panels a house needs shows how consumption turns into system size, and the best panel direction explains orientation.

Which equipment and warranty details matter?

Do not pick on panel rating alone. The quote should state the number of panels, their wattage, the inverter type, the racking and the monitoring. Compare warranties for each part, because panels, inverters and workmanship are covered separately and run for different lengths. A long panel warranty does little if the installer is gone. See solar panel warranties explained and solar inverter types for what to compare.

Ask how degradation is treated, and check that the system carries a recognised electrical certification for the province. Do not rely on brand names in a listing; look at the paperwork behind them.

How do you choose and vet an installer?

Collect at least three written quotes. Check licensing for electrical work in your province, business history, insurance, and references from recent customers with similar systems. Ask who actually does the roof work and the electrical connection, and whether subcontractors are used. Be wary of pressure to sign the same day, of savings claims with no calculation behind them, and of vague line items.

A fuller list is in the solar installer checklist, and how to compare solar panel quotes shows how to line up proposals on a common basis.

What should the contract and paperwork cover?

• Scope and price. System size, equipment list, what is included, and what triggers extra charges.
• Schedule and payment terms. Deposit size, milestones and completion date.
• Permits and utility connection. Who applies, who pays, and what happens if approval is delayed.
• Production estimate. The assumptions behind it; see how to read a solar production estimate.
• Warranties and service. In writing, with contact details and response expectations.
• Insurance and taxes. Tell your home insurer, and see the solar paperwork and tax checklist.

What about incentives, financing and the payback?

Treat any incentive as unconfirmed until you have read the current rules. Programmes have existed at federal, provincial and utility level, and their terms change. Check the Government of Canada energy-efficiency pages, your provincial energy ministry and your utility, and read the Canada solar incentives guide and solar financing options. Payback estimates should use your own electricity rate and a realistic share of power used on site, as set out in solar panel payback period.

For a sense of how long-lived solar infrastructure is judged, see the Drake Landing performance results, where output was tracked across many years.

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