Three photovoltaic (PV) technologies account for nearly all panels installed in Canadian residential projects: monocrystalline silicon, polycrystalline silicon, and thin-film. Each is manufactured differently, occupies a different market position, and performs differently in specific conditions. Understanding these distinctions helps homeowners and contractors select panels appropriate for a given roof geometry, budget, and climate.
Monocrystalline Silicon Panels
Monocrystalline panels are made from silicon ingots grown as a single continuous crystal using the Czochralski process. The resulting cells have a uniform dark appearance — typically black or very dark blue — and a distinctive rounded-corner shape in older designs; newer PERC and half-cut cell formats fill the full rectangular cell area.
Efficiency
Commercial monocrystalline panels available in Canada in 2025–2026 typically achieve module efficiencies of 20–23%. High-efficiency PERC (Passivated Emitter and Rear Cell) and TOPCon (Tunnel Oxide Passivated Contact) variants from manufacturers such as LONGi, Jinko, and Canadian Solar reach the upper end of that range. Higher efficiency means more power per square metre of roof area, which is valuable when available roof space is limited.
Temperature Coefficient
Monocrystalline panels typically have a temperature coefficient of around -0.30% to -0.35% per °C above 25°C. In Canadian summers, rooftop panel temperatures can reach 60–70°C under direct sun, which reduces output. During winter, cold temperatures actually slightly increase output relative to the rated value at STC (Standard Test Conditions of 25°C).
A monocrystalline silicon solar panel. Photo: Wikimedia Commons (CC)
Suitability for Canada
The combination of high efficiency, strong low-light performance (relevant in overcast provinces like British Columbia and Nova Scotia), and increasingly competitive pricing makes monocrystalline panels the dominant choice for residential installations across Canada. The higher upfront cost per watt compared to polycrystalline is partially offset by the smaller number of panels required to achieve the same system capacity.
Polycrystalline Silicon Panels
Polycrystalline panels are produced by melting raw silicon and casting it in moulds, which allows multiple crystal domains to form as it cools. The resulting cells have a distinctive speckled blue appearance. This manufacturing process is less energy-intensive and historically produced lower-cost panels, though the cost difference compared to monocrystalline has narrowed significantly since 2020.
Efficiency
Polycrystalline modules typically achieve efficiencies of 16–18%. This requires more roof area to achieve the same system output as a monocrystalline array. For homeowners with ample south-facing roof space and a tighter budget, polycrystalline remains a practical option, though their market share in new residential installations in Canada has declined as monocrystalline prices have fallen.
Temperature Performance
Temperature coefficients for polycrystalline panels are slightly worse than for monocrystalline, typically in the -0.38% to -0.42% per °C range. The practical difference in annual output between the two technologies due to temperature alone is modest in most Canadian climates, where extreme summer heat is less persistent than in southern US markets.
Thin-Film Panels
Thin-film PV deposits semiconductor material — most commonly cadmium telluride (CdTe) or copper indium gallium selenide (CIGS) — onto a substrate such as glass, metal, or polymer. The resulting panels are lighter and more flexible than crystalline silicon alternatives.
Efficiency and Form Factor
Commercial thin-film modules typically achieve 10–14% efficiency, though laboratory records for CIGS cells exceed 23%. The lower module efficiency means thin-film requires substantially more roof area per kilowatt than crystalline silicon, which limits its use in constrained residential applications. Thin-film is more commonly used in large commercial and utility-scale installations in Canada.
Advantages in Specific Conditions
Thin-film panels have a lower temperature coefficient than crystalline silicon (typically -0.20% to -0.28% per °C) and perform relatively better under diffuse or high-temperature conditions. Some products also have lower degradation rates under partial shading across the panel face compared to string-connected crystalline panels.
Residential application in Canada: Thin-film is rarely specified for standard residential rooftop installations in Canada due to the larger area requirement. Its primary residential relevance is in building-integrated PV (BIPV) applications — solar roof tiles, facades, or skylights — where the integration requirement justifies the lower efficiency.
Comparison Summary
| Property | Monocrystalline | Polycrystalline | Thin-Film (CdTe/CIGS) |
|---|---|---|---|
| Typical efficiency | 20–23% | 16–18% | 10–14% |
| Temperature coefficient | -0.30 to -0.35%/°C | -0.38 to -0.42%/°C | -0.20 to -0.28%/°C |
| Relative cost per watt | Medium–High | Medium | Varies (niche) |
| Area per kW | ~4.5–5 m² | ~5.5–6.5 m² | ~7–10 m² |
| Common residential use in Canada | Yes, dominant | Yes, declining | Limited (BIPV) |
| Low-light performance | Good | Moderate | Good–Excellent |
Panel Warranties and Degradation
Most crystalline silicon panels sold in Canada carry a 25–30 year linear power warranty guaranteeing that output will not fall below a specified percentage of rated power over the warranty period — typically 80% at year 25–30. Annual degradation rates are usually specified in the product datasheet and commonly range from 0.4% to 0.6% per year for quality crystalline panels.
Thin-film manufacturers typically offer similar warranty periods, and some CdTe products from First Solar have published strong field degradation data in utility-scale contexts.
When comparing panels, the temperature-corrected performance at actual site conditions and the warranty terms are more meaningful than peak wattage alone. Two panels with different rated outputs may produce nearly identical annual energy at a given Canadian location once temperature de-rating and degradation projections are applied.
Certifications Relevant to Canada
Panels installed on grid-connected residential systems in Canada must be certified to relevant standards. The CSA Group publishes standards for PV modules used in Canada, and certification to IEC 61215 (crystalline silicon) or IEC 61646 (thin-film) is expected. Panels listed on the Natural Resources Canada equipment eligibility lists for incentive programs must meet additional criteria depending on the program.
Related: How to Size a Residential Solar System — Choosing the Right Solar Inverter