Abstract
BACKGROUND: Climate vulnerability in sub-Saharan Africa, including Nigeria, has heightened concern about household energy transitions and associated health and economic impacts. Despite clean fuel initiatives, uncertainty remains regarding household expenditure patterns, health expenditures, and socioeconomic drivers of adoption. OBJECTIVES: To examine (1) household cooking-energy and respiratory healthcare expenditures, (2) descriptive expenditure ratios comparing energy costs with respiratory healthcare spending including benefits of transitioning to cleaner energy solutions, and (3) the socioeconomic determinants that influence households' willingness to transition to cleaner cooking practices. METHODS: A cross-sectional household survey was conducted in Alimosho (Lagos State) and Ado-Odo Ota (Ogun State) in southwest Nigeria. Using a multistage cluster sampling approach, 292 respondents from 200 households were surveyed on cooking-energy expenditures, respiratory healthcare costs, and willingness to adopt clean fuels. Expenditure patterns were compared descriptively, and a model-based cost-utility analysis was performed to estimate the incremental cost-effectiveness ratio in US dollars per disability-adjusted life-years (DALYs) averted. A multivariable logistic regression model was used to examine socioeconomic predictors of willingness to adopt clean cooking. RESULTS: Clean-fuel (liquefied petroleum gas or electricity) households reported higher annual cooking-energy expenditures than polluting-fuel households (US 25.08vsUS 16.27), as well as higher respiratory healthcare expenditures (US 112.50vsUS 50.64). The healthcare-to-energy expenditure ratio was also higher among clean-fuel users (4.48 vs 3.11). In adjusted analyses, tertiary education was associated with higher willingness to adopt clean cooking, while larger household size and urban residence were associated with lower willingness. In the model-based economic evaluation over a 1-year horizon, clean cooking was cost-saving (dominant) across plausible DALY-averted scenarios. CONCLUSIONS: Expenditure differences by fuel type likely reflect underlying socioeconomic conditions and variations in healthcare access, rather than causal effects of fuel choice. The model-based cost-utility analysis suggests that clean cooking could be cost-saving or highly cost-effective under plausible assumptions. Policies that address affordability and supply constraints, alongside stronger longitudinal evidence, are needed to support equitable and sustained clean-cooking transitions in Nigeria and across sub-Saharan Africa.