Analytical Study of the Effect of Climate Change on Building Energy Demand in Nigerian Cities Using Climate Projections

Climate change projections indicate rising temperatures across Nigeria that will substantially increase building cooling energy demand, and quantifying these effects analytically for major Nigerian cities is essential for building energy code development and long-term infrastructure planning. This study analytically estimated the effects of climate change on building energy demand across four representative Nigerian cities: Kano (hot dry), Lagos (hot humid), Abuja (hot semi-arid), and Calabar (tropical humid), using CMIP6 climate projection data under SSP2-4.5 and SSP5-8.5 scenarios for the 2050 and 2080 time horizons. EnergyPlus building energy simulations were conducted for three representative building archetypes (single-storey residential, multi-storey office, and single-storey institutional) using current and projected climate files developed using the CCWorldWeatherGen morphing methodology. Cooling degree days and heating degree days were calculated for current and future climates. Results showed that annual cooling energy demand is projected to increase by 23 to 38% by 2050 and 41 to 67% by 2080 across all cities and archetypes under SSP5-8.5. Kano showed the largest absolute cooling demand increases due to its existing high baseline temperature. Heating demand, already negligible, becomes zero in all cities by 2080 under both scenarios. Passive design adaptation measures (improved insulation, shading, and ventilation) were simulated to reduce but not eliminate projected demand increases. The study provides city-specific energy demand projections as inputs for the revision of the National Building Energy Code for 2030 to 2050 planning horizons.

Keywords: climate change, building energy demand, EnergyPlus, Nigerian cities, cooling energy