Evaluation of a Kirigami-inspired double-skin adaptive façade for natural ventilation and solar harvesting to enhance indoor environment and energy performance

A novel kirigami-inspired design concept for an environmentally responsive adaptive façade is presented and evaluated for the objectives of solar energy harvesting and adaptive ventilation through controllable surface orientation and opening. The concept is a double-skin façade where the outer skin includes a straight cut kirigami-inspired adaptive component. Controllable actuation of the kirigami-inspired section opens the outer skin for ventilation while also changing the orientation of the outer surface for solar tracking. The primary objective of this study is to evaluate the potential benefits for this concept integrated within a building façade for solar energy harvesting, air changes, and indoor temperature control. As such, a computational study is used to estimate the proposed facade concept's performance within various generalized building-environment scenarios. The methodology is detailed to computationally estimate the potential environmental performance of this concept with respect to solar harvesting with adhered solar panels, as well as air changes and HVAC cost for associated interior spaces. The example scenarios include various building components, from a single room to multiple building stories, and two geographic locations with significantly different environmental conditions, and both daily and yearly performance estimates are shown. The component is most effective when the outdoor temperature is near to the desired indoor temperature and wind speeds are mild, but can still reduce HVAC usage for more disparate temperatures. For example, in the scenarios shown the component can eliminate HVAC use for a $5°$C difference between outdoor and indoor temperature and reduces HVAC usage for temperature differences up to $15°$C. Moreover, the component has the potential to significantly increase net energy generation, with yearly performance estimated for the scenarios to be as much as 25% greater than that of a flat closed façade. However, the component cut parameters can have a significant impact on environmental performance, and thus require careful design consideration.