Parametric modeling approach for economic and environmental life cycle assessment of medium-duty truck electrification

Abstract

Using a parametric modeling approach, we evaluate economic and environmental life cycle trade-offs of medium-duty electric trucks in comparison with nine non-electric technologies (e.g., conventional diesel, biodiesel, compressed natural gas, etc.) for U.S. model year 2015. Life cycle results for electric trucks vary strongly with weighted positive kinetic energy, whereas those for non-electric trucks vary the most with average trip speed. Our parametric life cycle assessment models explain 91%–98% of the variability in life cycle inventory and impact assessment results, revealing “how” and “why” the trade-offs of truck electrification change with different input conditions.In terms of cost, whether total cost of ownership or also including health and climate impact costs, model year 2015 battery electric trucks in severe applications such as urban driving provide positive and robust net benefits in many areas of the U.S. However, for typical operations, petroleum diesel with idle reduction or hybrid-electric technology provide the largest overall life cycle cost benefit.Battery electric, idle reduction, and hybrid trucks emit lower life cycle greenhouse gas emissions across the board in comparison with the other technologies. Despite lower carbon-intensity, electric trucks tend to be water-intensive because of cooling water consumption for thermo-electric power plants. Hybrid trucks create higher NOx emissions and thus larger associated environmental impacts. Idle reduction is beneficial to urban-type applications. Compressed natural gas trucks are the least water-intensive but may not reduce greenhouse gas emissions. Using marginal rather than average factors for electric grid emissions calculations doesn't change the overall life cycle comparisons. Improving driving behavior has universally positive effects for which the exact magnitude and sensitivity depend on environmental impact indicators and technologies.