BIPV Performance

Solar irradiance - the amount of solar energy available at a given location - is the single largest determinant of BIPV energy output. It varies significantly by geography, climate, and elevation, and is measured in kilowatt-hours per square metre per year (kWh/m2/year). In Canada, Prairie provinces receive among the highest irradiance at 1,400-1,600 kWh/m2/year; Ontario and Quebec average 1,300-1,500 kWh/m2/year; BC's Lower Mainland and Atlantic Canada range from 1,100-1,300 kWh/m2/year. Building orientation determines which elevations generate most. South-facing facades receive maximum annual exposure. East and west elevations produce approximately 70-80% of south-facing output. North facades produce 40-60% - less than south, but significantly more than the zero output of conventional cladding.

• South facade: highest annual generation, strongest return per module.
• East and west facades: moderate generation, approximately 70-80% of south output.
• North facade: lowest generation but still meaningful - conventional cladding produces zero.

Beyond cardinal direction, the physical position of individual modules on the facade affects how much direct solar radiation each module intercepts. Horizontal modules capture more direct irradiance because a greater portion of the cell area faces skyward across the sun's annual path - horizontal configurations produce higher output per module. Vertical modules capture less direct radiation but align with standard cladding geometry on most commercial buildings, making full use of available facade area. Tilted modules represent the optimal configuration where architecturally feasible. The Mitrex eFacade TILT product addresses this directly, angling panels toward the sun to maximize the angle of incidence and increase annual energy capture.

Horizontal modules deliver higher output per module through greater direct irradiance capture, while vertical modules remain the standard for commercial facades, maximizing surface area deployment. For projects prioritizing maximum energy output, the eFacade TILT offers an angled configuration purpose-built to capture more sunlight.

Colour specification affects how much light reaches the photovoltaic cell layer through the glass facing. Mitrex's patented coating process maximizes light transmittance for every colour option - the coating is embedded in the glass rather than applied to the surface, making it permanent and scratch-resistant. Two additional proprietary coatings further improve performance: the anti-reflective (AR) coating reduces surface reflection, delivering up to 3.8% improvement in direct axis power and up to 4.7% improvement in total annual energy output. The anti-soiling coating prevents particulate adhesion, reducing soiling rates by up to 90% and sustaining output between cleaning cycles. Seasonality is expected - December and January output in Canadian markets is typically 40-60% lower than peak summer months due to shorter daylight hours and lower solar angle.

• AR coating: up to 4.7% improvement in total annual energy generation.
• Anti-soiling coating: up to 90% reduction in soiling rates vs. uncoated modules.
• Seasonal variation is normal and fully accounted for in annual energy projections.

Rooftop solar panels are optimally tilted and oriented for maximum energy capture - a south-facing 30-degree tilt in Toronto will outperform a vertical south-facing BIPV facade on a per-module basis. However, the comparison misses the point. The vertical facade area of a multi-storey commercial building is typically many times larger than its roof footprint. Full facade BIPV deployment generates substantially more total energy than rooftop panels alone, because it accesses a surface that conventional solar cannot use at all. BIPV and rooftop solar are complementary. Projects that deploy both maximize generation from every available surface. Cold temperatures do not reduce BIPV output - photovoltaic cells perform more efficiently in cold conditions than in extreme heat, making Canadian climates well-suited to year-round BIPV generation.

Facade surface area on multi-storey buildings far exceeds the available roof footprint, and since BIPV and rooftop solar are complementary, both can be deployed on the same building to maximize generation from every available surface. Cold temperatures also improve PV cell efficiency, making Canadian climates well-suited to year-round BIPV generation.

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