Progress in development of ultra-lightweight solar panel using space solar sheet

Development of an ultra-lightweight solar panel using space solar sheets is currently being carried out. The panel utilizes space solar sheets consisting of InGaP/GaAs dual-junction high-efficiency thin-film solar cells. The panel employs a simple frame-type structure. The initial breadboard model consisted of three main panels and two lateral panels. The dimensions of the 1.0-cm-thick unit panel were about 55 cm × 70 cm. In this study, the initial breadboard model was improved. The lateral panels were trimmed of weight while maintaining adequate stiffness. Additionally, unique deployment mechanisms for the lateral panels were adopted. The new system is much lighter than the conventional spring-driven mechanism, and as a result, the improved model finally achieved the high specific power of 100 W/kg.