## 1 Introduction  
Renewable energy generation technologies have been continuously developed owing to concerns related to the environment and energy independence. The rapid growth of photovoltaic (PV) technology compared to other renewables has led to numerous studies on this topic [1, 2]. As part of these studies, building-integrated photovoltaic (BIPV) systems play an essential role in generating electricity [3]. Recently, the BIPV market has been estimated to grow by approximately 40% per year from 2018 to 2026 [4]. In the case of BIPV, there are two limiting factors regarding the weight and installation area of the module to be installed [1, 2]. To solve these problems, it is necessary to study the design of high-power and lightweight c-Si PV modules for BIPV systems.  
Generally, glass is most commonly used for the front and rear covers in BIPV because it is a highly transparent, mechanically stable, and sustainable material that is familiar within the building industry. However, the weight of conventional PV modules with c-Si solar cells, ranging from 12 to 16 kg/m\({}^{2}\) for glass-backsheet modules and from 16 to 20 kg/m\({}^{2}\) for glass-glass modules, limits their usage on roofs or facades of buildings [5, 6]. Modules with a non-glass cover include a polymer such as ethylene tetrafluoroethylene copolymer (ETFE), polyamide (PA), polypropylene (PP), polyethylene terephthalate (PET), and polyvinyl fluoride (PVF), which are typically used for lightweight applications such as foods and facades of buildings [7, 8, 9, 10]. Although the lightweight PV module is very attractive, it is not yet applicable to BIPV owing to reliability and low module stiffness issues. The thin polymer sheet used to substitute the glass does not completely protect the solar cells owing to its low mechanical stability.  
Recently, many researchers have investigated the enhancement of the mechanical stability of lightweight PV modules for BIPV systems [7, 10, 11, 12, 13]. [PERSON] et al. employed an Al honeycomb sandwich structure at the rear of lightweight and mechanically stable c-Si PV modules [12; 13]. This glass-free and lightweight PV module architecture exhibited enhanced mechanical stability and reliability. However, conversion power enhancement of lightweight PV modules for BIPV systems has not yet been studied. In this study, we combined a shingled-type PV design for high-power conversion and glass-free lightweight module with an Al honeycomb sandwich structure on the rear side. The shingled-type c-Si PV module has a larger active area compared to the conventional PV module [14; 15; 16; 17; 18]. Because serially connected shingled-type strings do not have a busbar electrode on the front side this design increases the module power for the same installed area used in conventional PV modules. In our previous work, we fabricated an 1100 mm \(\times\) 1980 mm shingled-type c-Si PV module and performed conversion power and standard reliability tests [15]. Based on the combination of a shingled-type design and an Al honeycomb sandwich structure, we fabricated a high-power, lightweight c-Si PV module and analyzed the electrical properties and reliability of the PV modules.