Big automotive manufacturers are stepping up the production of electric trucks as a core strategy to decrease the greenhouse gas emissions of their vehicles.
Life cycle greenhouse gas emissions for each vehicle class and powertrain. Average lifetime emissions account for differences in grid emissions for electricity balancing areas and county-level differences in drive cycle and temperature effect on fuel economy. Image credit: From Woody et al. in Environmental Research Letters, 2022.
Light-duty vehicles, including SUVs sedans, and pickup trucks, are, at present, accountable for 58% of greenhouse gas emissions in the United States transportation sector. In 2020, pickup trucks were accountable for 14% of light-duty vehicle sales in the United States, and the market share of both SUVs and pickups has increased in the last few years.
But what impact will pickup truck electrification really have on the decarbonization of the transportation sector?
Researchers from the University of Michigan and Ford Motor Co. answered this question in a new study and measured the savings in greenhouse gas emissions in relation to gasoline-powered pickup trucks. The study has been published in the March 1st online issue of the journal Environmental Research Letters.
This is an important study to inform and encourage climate action. Our research clearly shows substantial greenhouse gas emission reductions that can be achieved from transitioning to electrified powertrains across all vehicle classes
Greg Keoleian, Study Senior Author and Professor, School for Environment and Sustainability, University of Michigan
During the study, scientists performed a cradle-to-grave assessment of the life cycle of pickup trucks and compared the effects of pickup truck electrification to those of SUV and sedan electrification.
With an emphasis on measuring greenhouse gas emissions, the scientists examined three diverse model-year 2020 powertrain options — hybrid-electric vehicles, internal-combustion-engine vehicles, and battery-electric vehicles — for midsize SUVs, midsize sedans and full-size pickup trucks, responsible for differences in fuel economy, vehicle production, annual mileage, and vehicle lifetime across vehicle classes.
They discovered that for SUVs, sedans and pickup trucks, battery-electric vehicles have around 64% lower cradle-to-grave life cycle greenhouse gas emissions compared to internal-combustion-engine vehicles on average spanning the United States.
This study can help us to understand the potential impact of electrification from an emissions-reduction perspective, particularly as we introduce new electric vehicles, and how we can continue to accelerate our progress towards carbon neutrality. We’re proud to partner with U-M in this critical work.
Cynthia Williams, Global Director of Sustainability, Homologation, and Compliance, Ford
The research delivers many key findings. Scientists, for instance, learned that substituting an internal-combustion-engine vehicle with a battery-electric vehicle resulted in better total tonnage of greenhouse gas emissions reductions as the vehicle size expands, because of the higher fuel consumption of larger vehicles.
Although the percentage savings is nearly the same throughout vehicle classes, on average, substituting an internal-combustion-engine SUV with a battery-electric SUV saves 56 metric tons of carbon dioxide equivalent; substituting an internal-combustion-engine sedan with a battery-electric sedan saves 45 metric tons of carbon dioxide equivalent; and substituting an internal-combustion-engine pickup with a battery-electric pickup saves 74 metric tons carbon dioxide corresponding to the lifetime of the vehicles, illustrated Max Woody, the study's first author and research expert at U-M’s Center for Sustainable Systems.
The team also discovered that battery-electric vehicles produce a greater percentage of greenhouse gas emissions in their manufacturing compared to internal-combustion-engine vehicles because of battery production, but this impact is counterbalanced by savings in their operation.
For internal-combustion-engine vehicles and battery-electric vehicles, the break-even time is 1.4 to 1.6 years for SUVs, 1.2 to 1.3 years for sedans, and 1.3 years for pickup trucks, based on the average U.S. grid and vehicle miles covered.
This study expands upon previous studies that have focused on comparing battery-electric vehicle sedans to their internal-combustion-engine or hybrid counterparts. We report emissions for vehicle production, use, and end-of-life stages on a per-mile basis and over the total vehicle lifetime.
Greg Keoleian, Study Senior Author and Professor, School for Environment and Sustainability, University of Michigan
Keoleian continued, “In addition, we analyzed the regional variation in emissions considering differences in electricity grid mixes and ambient temperatures, and we also explored the effects of the rate of grid decarbonization on emission reduction.”
Vehicle emissions differ across the country, as various temperatures and diverse drive cycles impact a vehicle’s fuel economy. For electric vehicles, the greenhouse gas emissions intensity of the local electricity grid is also a crucial factor.
The study created maps to display the lifetime grams of carbon dioxide equivalent/mile for each powertrain (hybrid vehicles, internal-combustion-engine vehicles, and battery-electric vehicles) and vehicle type (SUV, sedan, and pickup truck) by county spanning the United States.
Scientists learned that public concerns regarding battery-electric vehicles having greater emissions than internal-combustion-engine vehicles or hybrids are largely groundless, as battery-electric vehicles outclass hybrids in 95-96% of counties, while battery-electric vehicles outclass internal-combustion-engine vehicles in 98-99% of counties, even assuming only modest progress toward grid decarbonization.
Charging strategies can additionally decrease battery-electric vehicle emissions. The research learned that charging during the daytime with the lowest grid emissions intensity can lower emissions by 11% on average.
Deployment of electric vehicles and expansion of renewable energy resources like solar and wind should be done at the same time. The benefit of each is increased by the development of the other.
Max Woody, Study First Author and Research Expert, Center for Sustainable Systems, University of Michigan
Keoleian is also the director of the Center for Sustainable Systems. The study’s other authors include Parth Vaishnav of the U-M School for Environment and Sustainability and Center for Sustainable Systems, and Robert De Kleine, Hyung Chul Kim, James Anderson, and Timothy Wallington of Ford Motor Company’s Research and Innovation Center.
The research received support from Ford Motor Co. through a Ford-University of Michigan Alliance Project Award.
Journal Reference:
Woody, M., et al. (2022) The role of pickup truck electrification in the decarbonization of light-duty vehicles. Environmental Research Letters. doi.org/10.1088/1748-9326/ac5142.
Source: https://umich.edu