Assessment of Energy and Environmental Impacts of Transition from Road to Rail Passenger Transportation: A Case Study of Tanzania's SGR Electric Train

The study assesses the energy and environmental impacts of transitioning from road to rail passenger transportation in Tanzania, with a focus on the Dar es Salaam–Dodoma corridor, which is served by the newly implemented Standard Gauge Railway (SGR) electric train. Tanzania's heavy reliance on diesel-powered road transport contributes to high fuel consumption and significant greenhouse gas emissions. This research evaluates the SGR as a sustainable alternative, powered primarily by hydropower. Using a mixed-methods approach, the study collected and analysed data from the Tanzania Railway Corporation, transport authorities, and utility providers to compare energy consumption and emissions between the SGR electric trains and conventional diesel buses operating on the same route. Findings reveal that the SGR transports 4,231 passengers daily across five train services, equivalent to 89 conventional buses. Electric trains consume approximately 9,065.21 kWh daily, while buses require 160,378.00 kWh to transport the same passenger volume, representing a daily energy saving equivalent to 14,275 diesel litres. Environmentally, SGR operations generate only 2.982 tCO₂e per day, compared to 40.548 tCO₂e from buses, resulting in a substantial daily reduction of 37.566 tCO₂e in emissions. The analysis demonstrates that electric rail transport consumes 4.15–4.74 kWh per kilometre and 1.92–2.85 kWh per passenger, which is significantly lower than buses, at 54.06–94.61 kWh/km and 36.99–38.27 kWh/passenger. Similarly, emissions per passenger-kilometre are markedly lower for rail transport across all metrics. These results confirm that transitioning from road to electric rail passenger transport offers substantial energy efficiency gains and environmental benefits, supporting Tanzania's sustainable development objectives and climate commitments. The study provides empirical evidence for policymakers to prioritise rail infrastructure expansion, reducing the transport sector's carbon footprint while meeting growing mobility demands in an economically and environmentally sustainable manner.