Estimation of rainfall and wind impacts on fuel consumption of passenger vehicles: A physical model approach

With the continuous changes in climate, increased attention is required to address the adverse impacts of climatic variables on automobile fuel consumption and emissions. In recent studies, various prediction models have been employed to quantify the influence of weather-related factors on vehicular fuel consumption. The paper introduces three interrelated vehicle-based physical models designed to quantify the effects of rainfall and wind speed/direction on fuel consumption of four commercial vehicles - Matiz, Astra, Pregio, and Urvan, utilizing monthly weather data from Accra. The results indicated that the presence of headwind and rainfall substantially increased fuel consumption, whereas tailwind contributed to a reduction. Fuel increments under rainfall and headwind ranged from 2% to 10% and 4% to 16%, respectively across the vehicles, depending on the monthly variation in weather intensity. Conversely, the reduction in fuel consumption due to tailwind ranged between 1% and 3%, insufficient to counteract the more significant increases induced by headwind. The combined impact of rainfall and wind increased fuel consumption by 10% to 37% relative to the effect of rainfall alone and by 5% to 66% compared to headwind effects, depending on monthly intensity levels. The proposed models demonstrated robust performance in analyzing weather-induced fuel consumption and can be effectively applied to estimate offline vehicular fuel usage prior to a journey.