==Proceedings:All accepted (Registered & Presented) papers of REEE 2020 will be collected in the E3S Web of Conferences (Open Access proceedings in Environment, Energy and Earth Sciences)and submitted for indexing by CPCI (Web of Science), Scopus and Ei Compendex. ==Special Issue-Energies(ISSN 1996-1073)Energies is a peer-reviewed open access journal of related scientific research, technology development, engineering, and the studies in policy and management and is published monthly online by MDPI, which is indexed by the Science Citation Index Expanded (Web of Science), Ei Compendex, Scopus and other databases. Impact Factor: 2.707 (2018) ;5-Year Impact Factor: 2.990 (2018) ==History:REEE 2018 proceedings are published online (E3S Web of Conferences,Volume 80,2019),indexed by Ei Compendex & Scopus already. REEE 2019 proceedings are published online (E3S Web of Conferences,Volume 122,2019),indexed by Ei Compendex & Scopus already. ==Committee:Conference Chair:Prof. Elmar Bollin, Offenburg University of Applied Sciences, Germany Program Chairs:Prof. Jin Su Jeong, Universidad de Extremadura, Spain;Prof. Jorge Loredo, University of Oviedo, Spain;Prof. Aurel Lunguleasa, Transilvania University of Brasov, Romania. Technical Committee:Prof. Silvia Brunoro, University of Ferrara, Italy;Assoc. Prof. Patrizia Beraldi, University of Calabria, Italy;Prof. Florinda Martins, ISEP, Portugal;Dr. LU Lin, The Hong Kong Polytechnic University, Hong Kong;Assoc. Prof. Magdalena Ligus, Wroclaw University of Economics, Poland;Assoc. Prof. Chong Wen Tong, University of Malaya, Malaysia;Assoc. Prof. Mohammad Salah, Hashemite University, Jordan;Asst. Prof. Cheung Sai Hung, Nanyang Technological University, Singapore;Assoc. Prof. Anas Al Tarabsheh, Abu Dhabi University, United Arab Emirates;Assoc. Prof. Issa Etier, Hashemite University, Jordan;Assoc. Prof. Mohammad Lutfi b. Othman, Universiti Putra Malaysia, Malaysia;Assoc. Prof. Jasronita bt. Jasni, Universiti Putra Malaysia, Malaysia;Dr. Tanzeel-ur-Rashid, UET Taxila, Pakistan;Prof. Kuo-Lung Lian, National Taiwan University of Science and Technology, Taiwan;Prof. Krishnamachar Prasad, Auckland University of Technology, New Zealand.