Solar for nearly every façade surface

A study of the potential energy offset utilizing ClearVue Solar Vision Glass and Spandrel for the façade of a 40-story office building

Independent analyst firm, Footprint was engaged by ClearVue Technologies Ltd. to develop a 40-story energy efficient archetype office model with the objective of evaluating the efficacy of selected energy strategies in pursuit of a net zero energy design.

Integral to the design is a ClearVue PV building integrated photovoltaic (BIPV) system. The BIPV window glazing panels are rated to generate 29 W/m2 electricity while the opaque walls include spandrel panels with ClearVue PV dark glass which have a generation capacity of 200 W/m2.

This report examines a 40-story office building archetype energy model which has BIPV in both glazing and spandrel panels and a rooftop photovoltaic (PV) array. The report compares the energy performance of the models with 40%, 50%, 60%, and 70% window-to-wall ratios (WWR). The model presents the energy performance of a low carbon energy efficient design along with the renewable energy generation of the on-site photovoltaic arrays.

• This report identifies the renewable output from the high-rise office building archetype with ClearVue PV on glazing and dark spandrel panels among 15 international cities.
• It shows that BIPV helps considerably reduce both energy use intensity and greenhouse gas emissions in seeking to meet the Toronto Green Standard absolute intensity target values.
• For the model with 40% WWR, buildings in 11 cities are able to achieve Net Zero or Net Positive Energy with the building mounted PV arrays. All sites had over 85% of their annual consumption generated by the building mounted photovoltaic systems.
• As the window-to-wall ratio of the buildings was increased, the area of the higher W/m² BIPV spandrel panel was offset by glazing reducing the overall building renewable generation while the building cooling load increased. However, even at 70% window-to-wall ratio, all locations of the Archetype 40 storey model had more than 50% of their annual energy generated by the building mounted PV arrays.
• The emissions savings by the PV systems varied with the jurisdiction emissions factor as well as with the location solar resource but ranged up to over 1,500 to 1,600 tonnes of CO2e (43 kg-CO2e/m² of gross floor area) in regions with high solar availability and higher emissions factors.