Life cycle assessment of city buses powered by electricity, hydrogenated vegetable oil or diesel

Authors

Anders Nordelöf
Mia Romare
Johan Tivander

Document Type

Journal Article

Publication Date

2019

Subject Area

place - europe, place - north america, mode - bus, technology - alternative fuels, technology - emissions, planning - environmental impact, infrastructure - vehicle

Keywords

LCA, City, Bus, Battery, Electric, Vehicle, Plug-in, HVO, Diesel, Public transport

Abstract

This study explores life cycle environmental impacts of city buses, depending on the: (1) degree of electrification; (2) electricity supply mix, for chargeable options; and (3) choice of diesel or hydrogenated vegetable oil (HVO), a biodiesel, for options with combustion engine. It is a case study, which uses industry data to investigate the impact on climate change, a key driver for electrification, and a wider set of impacts, for average operation in Sweden, the European Union and the United States of America. The results show that non-chargeable hybrid electric vehicles provide clear climate change mitigation potential compared to conventional buses, regardless of the available fuel being diesel or HVO. When fueling with HVO, plug-in hybrid and all-electric buses provide further benefits for grid intensities below 200 g CO2 eq./kWh. For diesel, the all-electric option is preferable up to 750 g CO2 eq./kWh. This is the case despite batteries and other electric powertrain parts causing an increase of CO2 emissions from vehicle production. However, material processing to make common parts, i.e. chassis, frame and body, dominates the production load for all models. Consequently, city buses differ from passenger cars, where the battery packs play a larger role. In regard to other airborne pollutants, the all-electric bus has the best potential to reduce impacts overall, but the results depend on the amount of fossil fuels and combustion processes in the electricity production. For toxic emissions and resource use, the extraction of metals and fossil fuels calls for attention.

Rights

Permission to publish the abstract has been given by Elsevier, copyright remains with them.

Comments

Transportation Research Part D Home Page:

http://www.sciencedirect.com/science/journal/13619209

Recommended Citation

Nordelöf, A., Romare, M., & Tivander, J. (2019). Life cycle assessment of city buses powered by electricity, hydrogenated vegetable oil or diesel. Transportation Research Part D: Transport and Environment, Vol. 75, pp. 211-222.