Considering greenhouse gas emissions in maintenance optimisation

Keywords Maintenance policy; Greenhouse gas emissions; Condition-based monitoring; Two time scales; Integer nonlinear programming Highlights * The paper considers the greenhouse gas emission of a system as a degradation process. * It also considers the failure process due to other causes. * It proposes two methods to model the bivariate stochastic process. * Maintenance policies are proposed to optimise the expected cost rate. Abstract Greenhouse gases (GHG) from human activities are the main contributor to climate change since the mid-20th century. Reducing the release of GHG emissions is becoming a thematic research topic in many research disciplines. In the reliability research community, there are research papers relating to reliability and maintenance for systems in power generation farms such as offshore farms. Nevertheless, there is sparse research that aims to optimise maintenance policies for reducing the GHG emissions from systems such as automotive vehicles or building service systems. To fill up this gap, this paper optimises replacement policies for systems that age and degrade and that produce GHG emissions (i.e., exhaust emissions) including the initial manufacturing GHG emissions produced during the manufacturing stage and the emissions generated during the operational stage. Both the exhaust emissions process and the failure process are considered as functions of two time scales (i.e., age and accumulated usage), respectively. Other factors that may affect the two processes such as ambient temperature and road conditions are depicted as random effects. Under these settings, the decision problem is a nonlinear programming problem subject to several constraints. Replacement policies are then developed. Numerical examples are provided to illustrate the proposed methods. Author Affiliation: (a) Kent Business School, University of Kent, Canterbury, Kent CT2 7PE, United Kingdom (b) School of Management, Xi'an Jiaotong University, Xian, China (c) School of Economics and Management, Beijing University of Technology, Beijing 100124, China * Corresponding author. Article History: Received 3 November 2021; Accepted 3 October 2022 Byline: Shaomin Wu [s.m.wu@kent.ac.uk] (a,*), Di Wu (b), Rui Peng (c)