Argonne releases new cradle-to-grave lifecycle analysis of US LDV vehicle-fuel pathways
06 August 2022
Argonne National Laboratory has published a new cradle-to-grave (C2G) lifecycle analysis (LCA) of US LDV vehicle-fuel pathways. The report was prepared by Argonne researchers and members of the US Drive Integrated Systems Analysis Technical Team. This analysis builds on a previous comprehensive life cycle analysis, updating that study’s 2016 assumptions and methods.
US Drive—United States Driving Research and Innovation for Vehicle efficiency and Energy sustainability—is a government-industry partnership among the US Department of Energy; USCAR, representing Stellantis, Ford Motor Company, and General Motors; five energy companies (BP America, Chevron Corporation, Exxon Mobil Corporation, Phillips 66 Company, and Shell); three utilities (Southern California Edison, Michigan-based DTE Energy, American Electric Power); and the Electric Power Research Institute.
The study provides a comprehensive analysis of the cost and greenhouse gas (GHG) emissions of a variety of vehicle-fuel pathways; the levelized cost of driving (LCD); and the cost of avoided GHG emissions. The C2G analysis assesses light-duty midsize sedans and small sport utility vehicles (SUVs) across a variety of vehicle-fuel technology pathways, including conventional internal combustion engine vehicles (ICEVs); flexible hybrid electric vehicles (HEVs); plug-in hybrid electric vehicles (PHEVs); battery electric vehicles (BEVs) with varying vehicle ranges; and fuel cell electric vehicles (FCEVs).
The 2022 report accounts for a broader range of vehicle technologies and considers both current (2020) and expected future (2030-2035) conditions. Reflecting increased research interest in synthetic liquid fuels produced using renewable low-carbon electricity and CO2 sources, e-fuels were added to the potential future fuel technologies that are evaluated.
Selected fuel pathways were constrained to those deemed to be nationally scalable in the future. Additional concerns, such as consumer choice, regional variability, and infrastructure availability for FCEV and BEV, were not directly accounted for. High production volume is assumed unless explicitly specified. The electricity mix used in stationary processes (unless otherwise specified) comes from the 2035 US grid generation mix projected by the US Energy Information Administration (EIA) in the Annual Energy Outlook (AEO) 2021.
Fuel production pathways considered
The GHG emissions evaluation was carried out by expanding and modifying Argonne’s GREET model suite (2020 version) with inputs from industrial experts. This C2G GHG assessment includes both fuel and vehicle production life cycles. Cost assessments represent a final cost/price to the consumer, excluding taxes on the final product (e.g., fuel sales tax) and/or credits (e.g., vehicle subsidies).
Vehicle fuel economies and component sizes were estimated using Argonne National Laboratory’s vehicle simulation tool, Autonomie, using a consistent set of vehicle performance criteria across vehicle-fuel combinations.
The main case presented in the body of the report is the high powertrain technology progression pathway with the central cost cases for each fuel. The ranges presented in the cost analyses include the low technology progression vehicle coupled with the high fuel cost (when available, and the central case when not), and the low range is the high technology progress with the lowest fuel cost (when available).
By far the largest and the most consequential change in the input assumptions between the 2016 study and this current update is in battery costs for BEVs. The past 5-10 years have seen dramatic reductions in the cost of EV batteries while, similarly, battery cost projections have also changed significantly over the past 5 years. It is hard to overstate the importance of the improvements in battery costs on this analysis.
—“Cradle-to-grave lifecycle analysis of US light-duty vehicle-fuel pathways” (2022)
C2G GHG emissions of various vehicle-fuel pathways for small SUVs assuming high technology progress. The down-arrows show a plausible reduction of the carbon footprint of the vehicle-fuel pathway from low-carbon fuels and electricityANL.
The modeled costs of avoided GHG emissions for the majority of future technology cases, considering the full 15-year vehicle lifetime, are below $200/tonne CO2e with many options below zero—i.e., they cost less than the ICEV and emit fewer emissions.
Additionally, the BEV400 and FCEV pathways are markedly different from the current technology case. The cost of those technologies, though still a major component of overall vehicle cost, is modeled to improve significantly over the intervening period, leading to a much lower total vehicle cost.
Lifetime cost versus GHG emissions by vehicle-fuel pathway for the Future Technology case for small SUVs (2020$). ANL
For the future technology case, HEV, PHEV, and BEV platforms offer the lowest modeled costs of avoided GHG emissions, with many options having a negative cost—i.e., the cost is less than that of the gasoline ICEV. The FCEVs offer lower cost GHG emissions opportunities than the ICEV technologies with the exception of the E85 vehicle operating on corn stover and the CNG vehicle operating on RNG.
The over-arching observation drawn from the report is that large GHG reductions for LDVs are achievable through low-carbon fuel pathways, with vehicle efficiency improvements also playing an important role. Low-carbon fuels can have significantly higher costs than conventional fuels; however, vehicle cost is the major (60–90%) and fuel cost the minor (10–40%) component of LCD.
This analysis, which of course using GREET is highly robust in many respect, is of course dependent on the assumptions and boundary conditions used.
My view would be that developments such as, but not limited to, this more efficient electrolyser from Hysata:
https://www.greencarcongress.com/2022/08/20220805-hysata.html
Should enable, certainly in the US, largely on site production of hydrogen from nearby solar resources, greatly reducing costs and improving efficiency.
I would note though that they have not done anything daft, like assuming current costs for hydrogen in California continue indefinitely - on page 37 they give $4gge as their assumption for electrolysis using solar and wind.
They do seem to have used present efficiencies for electrolyser throughout though, as far as I can see ( page 28), and assume that solar and wind is not produced on site.
In addition, this analysis does not include fuel cell/ battery plug in hybrids, which eliminate the extreme pressure on resources and hassle of lugging around thumping great batteries whilst covering day to day running around with somewhat more efficient battery electric propulsion.
Not that I have anything against batteries, if they are made in sufficiently earth abundant materials, and hopefully lighter and more compact.
CATL's sodium batteries spring to mind.
Another area outside the analysis is high temperature PEMS using methanol etc. which might be rather less efficient but would be heckuvva convenient
Posted by: Davemart | 06 August 2022 at 02:31 AM
I would also point out that folk who state that they charge their cars from solar on their roof mostly don't.
They charge them at night, when the sun don't shine.
Of course, there are ways around it, ranging from spells and incantations to offsets, or more realistically to home battery set ups, but that costs money and energy to make the extra batteries and reduces efficiency, touted as the great benefit of BEVs.
I would like to see in the US car parks etc routinely covered by solar arrays, which really would make plugging in very energy efficient.
But any analysis of comparative merits has to take into account some degree of storage for the electricity to supply BEVs, something which is inherent in using hydrogen etc.
That is going to be in Argonne's calculations here, but many folk routinely pretend it does not exist as an issue.
Posted by: Davemart | 06 August 2022 at 03:02 AM