sustainability Article Techno-Economic Assessment of Energy Retrofitting Educational Buildings: A Case Study in Saudi Arabia Mohammad B. Hamida 1,2 , Wahhaj Ahmed 1 , Muhammad Asif 1, * and Faris Abdullah Almaziad 3   Citation: Hamida, M.B.; Ahmed, W.; Asif, M.; Almaziad, F.A. Techno-Economic Assessment of Energy Retrofitting Educational Buildings: A Case Study in Saudi Arabia. Sustainability 2021, 13, 179. https://dx.doi.org/10.3390/ su13010179 Received: 2 December 2020 Accepted: 23 December 2020 Published: 27 December 2020 Publisher’s Note: MDPI stays neu- tral with regard to jurisdictional claims in published maps and institutional affiliations. Copyright: © 2020 by the authors. Li- censee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/ licenses/by/4.0/). 1 Architectural Engineering Department, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia; mohammed.b.humaidah@gmail.com (M.B.H.); wahhaj156@gmail.com (W.A.) 2 Department of Management in the Built Environment, Faculty of Architecture and the Built Environment, Delft University of Technology, 2628 BL Delft, The Netherlands 3 Department of Building Engineering, College of Architecture and Planning, Imam Abdulrahman Bin Faisal University, Dammam 31451, Saudi Arabia; fmaziad@iau.edu.sa * Correspondence: asifm@kfupm.edu.sa; Tel.: +966-13-860-7906 Abstract: The buildings and construction sector accounts for the majority of the energy consumption in the Kingdom of Saudi Arabia (KSA). For a sustainable future, energy consumption in the sector should be reduced and existing buildings need to be energy retrofitted. A number of studies present energy retrofitting of residential buildings in KSA; however, there is a lack of studies presenting retrofitting of educational buildings. Thus, the aim of this study is to adopt a BIM-based approach to assess Energy Conservation Measures (ECMs) in a prototypical Government-built educational build- ing in Dammam, KSA. The methodology consists of six prime steps, (1) case study data collection, (2) energy auditing, (3) proposing ECMs, (4) BIM model development, (5) energy assessment, and (6) economic assessment. The energy audit revealed several inefficiencies in the building construction and operation and four ECMs were proposed and simulated. It was found that annual energy consumption can be reduced by 22.7% in the educational building, and the investment for the four ECMs is paid back in 2.7 years only. Therefore, implementing the proposed ECMs is a viable option to energy retrofit such educational buildings in the country, and the presented BIM-based approach can be adopted to efficiently conduct the energy retrofitting process. Keywords: educational buildings; energy efficiency; energy auditing; Energy Conservation Measures (ECMs); sustainability; KSA 1. Introduction Presently, climate change is one of the most serious threats to society. Climate change is evident around the world in the form of rapidly increasing number of natural disasters and rate of global warming. Countries globally are introducing initiatives and measures to mitigate the effects of climate change. The buildings and construction sector is one of the biggest contributors to climate change, and accounts for more than 40% of the materials consumption, 30% of the total global energy consumption, and more than one- third greenhouse gas emissions globally [1]. In the past century, some areas of the earth have experienced an increase in temperature by 2.5 ◦ C[2]. According to estimates, a 77% reduction in total Carbon Dioxide (CO 2 ) emissions in the buildings and construction sector is necessary to limit the increase in temperature of Earth by 2 ◦ C by 2050 [3]. To achieve this target, some of the developed countries have already introduced energy efficiency measures and trends indicate a reduction in the rate of CO 2 emissions [4]. However, the same cannot be said of the developing nations where CO 2 emissions is constantly on the rise. The Kingdom of Saudi Arabia (KSA) is a developing country with one of the highest energy consumption trends in the world, and this is evident from the fact that the per capita energy consumption in Saudi Arabia is almost threefold higher than that of the global Sustainability 2021, 13, 179. https://dx.doi.org/10.3390/su13010179 https://www.mdpi.com/journal/sustainability