INTERNATIONAL JOURNAL of RENEWABLE ENERGY RESEARCH M. H. Mubarok et al., Vol.9, No.4, December, 2019 Mapping Technological Trajectories of Crystalline Silicon (c-Si) PV Using Patent Analysis Muhammad Husni Mubarok*, Ully Yunita Nafizah**‡, Muhammad Yorga Permana*** *Energy Academy Indonesia (ECADIN) ** Faculty of Industrial Engineering and Information System, Telkom University, Bandung, Indonesia *** School of Business and Management, Institut Teknologi Bandung, Bandung, Indonesia (m.h.mubarok@ecadin.org, ullyyunita@telkomuniversity.ac.id, yorga.permana@sbm-itb.ac.id) ‡ Corresponding Author; Ully Yunita Nafizah, Bandung, Indonesia, Telp: +628122175994, ullyyunita@telkomuniversity.ac.id Received: 14.10.2019 Accepted:20.11.2019 Abstract- This paper is the first to identify the technological development of crystalline silicon (c-Si) PV technology by analyzing network patent and main trajectory. The data used is the US granted patent from 1976 until 2010, thus resulted of 1,100 patents data. The network of patent citation data is analysed based on the key network measure (i.e., number of nodes, density, in-degree centrality, and out-degree centrality) and followed by developing the network trajectory. The main path analysis is obtained by using both SPLC method (Search Path Link Count) and the SPNP method (Search Path Nodes Pair). The main path further is analyzed along with its sub-path to understand the evolution of c-Si PV technology. The results indicate that: 1) the c-Si Solar cells technology has very low network density which means the patents are sparsely connected with each other, 2) The connected patents are the representative of the 'new' thin-film solar technology, 3) The most cited patent is not a part the main trajectory, meaning that there is a low correlation between patent and technology development, 4) The US, Japan, and Germany are the main actors in c-Si solar cells technology. US and Germany are identified as key pioneers during the early stage of this technology, while Japan appears at later stages, 5) Siemens is the main actor in the initial c-Si PV technology. Keywords Crystalline silicon (c-Si) PV technology, Network patent analysis, Technology development, Technology trajectory 1. Introduction With the growing concerns of energy security and climate change, research and development efforts for reducing the world's dependence on fossil fuel are intensified. As a result, various sustainable energy technologies from renewable energy sources has been flourished in the past decade; its average growth is 5.4% in the last ten years [1]. Moreover, the share of renewable energy in the energy mix is expected to rise from 15% by 2017 to reach 60% by 2050 in order to meet the Paris agreement [2]. The power sector is expected to contribute to a higher share of renewables in the energy mix as electricity is becoming more and more favourable as the form of end-use energy by the world’s population. Power generation from renewables is experiencing a remarkable growth [3] with one technology stand out among others: Solar Photovoltaic (PV) technology, 55% of newly installed renewables power plants in 2017 is from PV [1]. Many factors are attributed to the exceptional growth of solar PV technology apart from the decreasing cost of PV module [4], one of which is R&D of the PV technology. R&D is influential in technology development as it is a proxy for companies to create product development for the future. Moreover, the R&D of PV technology has been started as early as the 1850s, and it has yet shown any sign to stop in R&D with companies from various countries that are still developing PV technology. The state of the art of PV technology is a part of prior R&D that results in more than thousands of knowledge in PV technology. Both knowledge creation/development and knowledge diffusion are two of the essential seven functions in technological innovation system [5]. The knowledge development, as knowledge in other innovation, is fundamental in technological innovation as knowledge represents the function of learning by doing and learning by using [6]. Meanwhile, knowledge diffusion represents the exchange of information between actors in the field [5]. We argue that the exceptional growth of solar PV can be associated with a strong network of linking knowledge within PV technology, thus enabling a positive environmental condition for R&D to develop appropriate technology.