Examining the relationship between dwelling energy efﬁciency and fuel poverty for retroﬁt strategies: A case study of the United Kingdom Minghao Liu , Zhonghua Gou * School of Urban Design, Wuhan University, Wuhan, China A R T I C L E INFO Handling editor: X Zhao Keywords: Fuel poverty Energy crisis Retroﬁts Household conditions Machine learning ABSTRACT In the midst of a global energy crisis, fuel poverty has become increasingly prevalent. This study examines the effectiveness of energy efﬁciency retroﬁts (EERs) in alleviating fuel poverty in the United Kingdom. Using the England fuel poverty dataset with XGBoost and interpretive analyses like Individual Conditional Expectation (ICE) and SHapley Additive exPlanations (SHAP), the research investigates the impact of EERs on fuel poverty. Findings reveal that while energy efﬁciency enhancements hold potential for improving conditions for vulner- able households, their effectiveness diminishes beyond a certain threshold. The study identiﬁes solid wall and cavity wall insulation, condensing boilers, well-insulated lofts, and central heating systems as the most effective retroﬁt measures. However, the optimal selection of retroﬁt methods varies depending on household and dwelling conditions due to interactive effects. Additionally, comprehensive cost-efﬁciency analyses show that installing condensing combination boilers in homes without existing boilers and adding cavity wall insulation to houses with uninsulated cavity walls are more cost-efﬁcient options. These insights shed light on the complex relationship between energy efﬁciency retroﬁts and fuel poverty, informing the development of targeted stra- tegies to address this pressing issue in the UK and globally. Abbreviations: Abbreviation Full Name AFCP After Fuel-Cost Poverty BEIS Department for Business, Energy, and Industrial Strategy CWI Cavity Wall Insulation ECO Energy Company Obligation EER Energy-efﬁcient Retroﬁtting EPC Energy Performance Certiﬁcate EPG Energy Performance Gap EWI External Wall Insulation ICE Individual Conditional Expectation LIHC Low Income High Cost OLS Ordinary Least Squares OR Odds Ratio SAP Standard Assessment Procedure SHAP SHapley Additive exPlanations SWI Solid Wall Insulation XGBoost eXtreme Gradient Boosting 1. Introduction Energy poverty or fuel poverty is a pressing global issue with far- reaching implications for health, education, and overall quality of life [1]. Furthermore, recent global crises, including the sovereign debt crisis, Brexit, the COVID-19 pandemic, and the Russia-Ukraine war, have caused rising energy prices and shortages, worsening energy poverty or fuel poverty [2–7]. Energy poverty or fuel poverty signiﬁ- cantly impacts the most vulnerable populations in both developing and developed countries [8–10]. It obstructs economic development, in- tensiﬁes inequalities, and hinders progress toward achieving the Sus- tainable Development Goals (SDGs) [1,11]. Addressing energy poverty is urgent, and energy efﬁciency retroﬁts provide a dual advantage: they not only reduce energy consumption but also help alleviate energy poverty. This article attempts to examine the relationship between dwelling energy efﬁciency and fuel poverty to guide retroﬁt strategies. Given the UK’s pioneering role in addressing energy poverty [12,13] and its provision of extensive data, this study focuses on the UK as a case study, aiming to offer suggestions for alleviating energy poverty glob- ally. The research investigates the impact of retroﬁt applicability, * Corresponding author. E-mail address: zh.gou@whu.edu.cn (Z. Gou). Contents lists available at ScienceDirect Energy journal homepage: www.elsevier.com/locate/energy https://doi.org/10.1016/j.energy.2024.133457 Received 14 July 2023; Received in revised form 5 September 2024; Accepted 12 October 2024 Energy 311 (2024) 133457 Available online 13 October 2024 0360-5442/© 2024 Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.