Insights from the evolution of transport technologies, 1800–2020: Energy use, transitions, and efficiency

The replacement of fossil fuels by electricity and other alternative fuels in transport will not be that sector's first energy transition. Using transport history as an analogue for the future can offer helpful insights for today's policymakers. The present work investigates the evolution of world energy use in the transport sector, identifying its energy transitions (at the final and useful stages), and evaluating the impact of past transitions on energy use over the period 1800–2020. To perform these analyses, a novel long-run dataset of energy use and efficiencies of water, rail, road, and air transport was developed. Our main findings are: (1) final energy use in transport increased 300-fold between 1850 and 2019, while useful energy rose 460-fold over the same period, (2) final-to-useful efficiency of the transport sector improved from 15 % to 23 % in the period 1850–2019, (3) the transport sector has experienced 3 transitions: from renewables to coal, from coal to oil products, and from oil to electricity and biofuels (ongoing), all of which lasted for several decades, and (4) past energy transitions in transport resulted in growth of final energy use, regardless of changes in final-to-useful energy efficiency (backfire). Moreover, this work concludes that the quality of energy services was an important driver of past transitions, a factor to be explored when adopting new technologies.