Experimental studies on summer performance and feasibility of a BIPV/T ethylene tetrafluoroethylene (ETFE) cushion structure system

Abstract

An ethylene tetrafluoroethylene (ETFE) cushion structure integrated photovoltaic panels is proposed for solar energy utilization of cushion structures. It can maintain cushion operation by photovoltaic electricity and provide a way of collecting thermal energy due to enclosed cushions. An experimental mockup composed of a three-layer ETFE cushion and amorphous silicon photovoltaic panels (a-Si PV) has been developed and a series of experiments have been conducted in summer, especially under sunny and sunny to cloudy conditions. On the whole, the experimental results showed that this system operated smoothly and steadily. In this paper, two studies, i.e. one-day study and three-day study have been done to investigate system performance and feasibility.For energy, the average stored electricity was 61Wh and the average ratio of consumption electricity to output electricity under sunny condition was lower than that under sunny to cloudy condition. Meanwhile, an average temperature difference between air temperatures inside and outside of the cushion was 18.1°C. Therefore, system electricity feasibility and potential in solar energy utilization have been verified. For cushion structures, temperatures on structural ETFE membranes used to resist external loads were within the acceptable range and pressure performance was satisfactory. Therefore, structure feasibility has been demonstrated.This study reveals the technical feasibility of ETFE cushion structure integrated photovoltaic. It provides a way to expand the application of building integrated photovoltaic/thermal (BIPV/T) to cushion structures.