Modelling Nigerian residential dwellings: bottom-up approach and scenario analysis

Nigeria's residential buildings consume a substantial amount of the country's energy, so achieving a net-zero building sector with a rapidly growing population is a key challenge. To bridge the gap in research at a national level and support Nigeria's commitment to an unconditional 20% reduction in emissions by 2030, this study develops bottom-up archetype models of different residential building typologies to estimate the energy and material use of Nigerian residential buildings. This creates an overview of the residential stock and how different archetypes perform. The study calculates a baseline energy and material use of Nigeria's residential building stock using the BuildME tool and converts these data into CO2 emissions using a life-cycle assessment. Scenarios are modelled for 2020. Nigeria's residential dwellings use approximately 0.3 kt of material per dwelling over a lifetime of 50 years and 2404 kWh/yr of energy per dwelling. Annualised, dwellings emit 2500 kgCO2-eq per dwelling due to material and energy use. Scenarios proposed for meeting Nigeria's emissions targets will require improved energy efficiency, decarbonising the building envelope through a shift in construction materials and decarbonising grid electricity. POLICY RELEVANCE This study provides a comprehensive analysis of the energy and material use of residential buildings in Nigeria, focusing on achieving the country's commitment to a 20% reduction in emissions by 2030. It employs a bottom-up approach to model energy and material use, revealing the peculiarities of the dwelling stock across Nigeria's four climatic zones. The study explores the implications of different policy scenarios on sustainable housing. The research suggests that meeting Nigeria's emissions targets requires improved energy efficiency, a shift in construction materials and decarbonisation of grid electricity. It also highlights the potential benefits of a policy switch to materials such as timber, earthen blocks, adobe bricks and clay, which could significantly reduce construction-related emissions. These changes could improve the quality of life of households in Nigeria, combat climate change on a global scale and bring economic advantages to Nigeria.