What makes one solar quote cost more than another

Why is system size the biggest factor?

A bigger system costs more in total, but usually less per watt, because fixed costs such as the site visit, permit work, electrical connection and project management are spread over more panels. That is why price per watt is a handy yardstick and why the same figure from a small and a large system should not be compared blindly. Our guide to solar price per watt explains how to use it.

The arithmetic is simple. If a quote for a 6 kW system is 12,000 dollars, that works out to 2 dollars per watt (12,000 divided by 6,000 watts). The figures here only show the division, not what quotes cost today. Size should come from your electricity use and roof space, not from a sales target, and how many solar panels you need shows how to estimate it.

Which equipment choices change the price?

• Panel grade. Higher-efficiency panels cost more per panel but need less roof for the same output, which helps on small roofs.
• Inverter type. A single string inverter is usually cheaper than micro-inverters or optimizers on each panel, but the latter can help with shade. See solar inverter types.
• Racking and mounting. Roof mounts are cheaper than ground mounts, and unusual roofs need special hardware.
• Monitoring and safety devices. Rapid-shutdown equipment and monitoring hardware add to the equipment list.
• Battery. A battery can add more than the panels themselves in some quotes; see solar battery storage in Canada.

What do labour, roof and site add?

Installation labour covers design, roof work, wiring, inspection and commissioning. A simple south-facing roof with a clear run to the electrical panel costs less to install than a steep, multi-faced roof with a long conduit run. Older homes may need an electrical service upgrade before a solar system can connect, which can add a noticeable amount. Roofs near the end of their life may need work first.

Winter access, snow loads and local labour markets influence price too. Regional price differences are real, and the solar panel cost in Alberta guide shows one provincial view, while solar panel cost in Canada gives the national picture.

What about permits, fees and sales costs?

Permits, inspections and utility connection fees vary by municipality and utility. Some installers include them in the price, others list them separately. Marketing and sales costs are also built in, and they vary a lot between a small local firm and a large door-to-door operation. Ask what is included, and see solar panel permits in Alberta for an example of the steps involved. Tax treatment of GST or HST on solar is covered in GST and HST on solar panels and rebates.

How do you compare quotes on a fair basis?

Ask each installer for system size in kilowatts, number and rating of panels, inverter model type, warranties, what is included for permits and connection, and the estimated yearly production with its assumptions. Divide each total by system watts, then adjust for equipment differences. Do not treat the cheapest quote as the best or the dearest as the safest. The guide on how to compare solar panel quotes goes line by line.

Incentives and loans change the net cost, but they come and go, so look at current terms on the Government of Canada energy-efficiency pages, your provincial energy ministry and your utility, as covered in the Canada solar incentives guide.

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