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Gohlke, David

Publications and source records attributed to Gohlke, David.

18 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Fleet-Level Energy and Emissions Analysis of the US Off-Road Sector with VISION: Off-Road

In the United States (US), the off-road sector (i.e., agriculture, construction, etc.) contributes to approximately 10% of the country’s transportation greenhouse gas (GHG) emissions, similar to the aviation sector. The off-road sector is extremely diverse; as the EPA MOVES model classifies it into 11 sub-sectors, which include 85 different types of equipment. These equipment types have horsepower ranging from 1 to greater than 3000 and have very different utilization, which makes decarbonization a complex endeavor. To address this, Argonne’s on-road vehicle fleet model, VISION, has been expanded to the off-road sector. The GHG emission factors for several energy carriers (biofuels, electricity, and hydrogen) have been incorporated from Argonne’s GREET model for a sector-wide well-to-wheel (WTW) GHG emissions analysis of the present and future fleet. Several technology adoption and energy decarbonization scenarios were modeled to better understand the appropriate actions required to drive towards net-zero emissions of the off-road sector. Results show that WTW decarbonization up to 67% can be achieved from 2023 to 2050 in a business-as-usual scenario. But with aggressive sales increases of electric and hydrogen powertrains, WTW decarbonization up to 77% can be achieved, which can further increase to 85% if electricity production is aggressively decarbonized by 2035.

lifecycle↗
DOE OSTI2024

Potential Adoption and Benefits of Co-Optimized Multimode Engines and Fuels for U.S. Light-Duty Vehicles

Exploring a diverse portfolio of technologies for decarbonization is crucial to understanding the potential impacts of different technological solutions and their associated environmental implications. Using high-octane, high-sensitivity biofuel blends in co-optimized multimode engines can increase engine efficiency and reduce vehicle emissions. Here, the multimode engine research focuses on the benefits of light-duty vehicle engines, which can operate in multiple modes depending on the vehicle's load. Low-temperature combustion can improve efficiency and reduce emissions (such as those from oxides of nitrogen and particulate matter) during low-load operation, while spark ignition performance is maintained in high-load operation. These advanced engines can be optimized to run on blends of biobased fuels. This analysis models scenarios for potential market adoption of co-optimized multimode vehicles fueled by three different bioblendstocks: ethanol, isopropanol, and isobutanol. An integrated modeling approach is used to forecast the energy and environmental impacts of the deployment of co-optimized multimode vehicles and fuels in the light-duty sector over the 2020-to-2050 time horizon. The multidisciplinary approach combines vehicle sales modeling, system dynamics modeling of the biorefining industry, and life cycle assessment to estimate the emissions and energy benefits. The models consider market forces such as consumer preferences for vehicle attributes, biofuel supply and demand dynamics subject to biorefinery capacity build-out and bioresource constraints, and forecasted changes to the U.S. bulk energy system over time. Market adoption of co-optimized vehicles is evaluated across a wide parameter space for incremental vehicle cost and engine efficiency improvement. This analysis reveals that the deployment of co-optimized multimode fuels and vehicles results in up to a 5% reduction in annual sector-wide life cycle greenhouse gas (GHG) emissions by 2050, relative to a business-as-usual scenario, but is also indicates environmental trade-offs, such as higher life cycle water-use. Emission benefits could potentially increase beyond 2050, as the new technologies penetrate the market and gain a foothold. Results also show that, under certain circumstances, vehicles with engines co-optimized for use with high-octane, high-sensitivity biofuel blends can be cost-competitive with conventional gasoline, while reducing GHG emissions. Our modeling results indicate that co-optimized multimode fuels and engines can be strategically leveraged in tandem with electrification to decarbonize the light-duty sector. Co-optimized vehicles could play a role in the early years of the time horizon, while electric vehicles (EVs) could become more competitive in the later years, highlighting the complementary benefits of these technologies for GHG reductions.

Oke, Doris↗
DOE OSTI2024

Refueling Infrastructure Deployment in Low-Income and Non-Urban Communities

The U.S. National Blueprint for Transportation Decarbonization identifies the need to invest in infrastructure supporting low- and zero-emission vehicles, especially in low-income and overburdened communities, to eliminate nearly all greenhouse gas emissions from the transportation sector by 2050. The alternative fuel vehicle refueling property tax credit (26 U.S. Code § 30C) includes eligibility criteria intended to encourage investment in underserved communities based on the economic characteristics or urban character of the census tract in which the fueling infrastructure is installed. Eligible census tracts are those that qualify for the New Markets Tax Credit or that are not located within urban areas as defined by the U.S. Census Bureau. This study quantifies how many fueling-related amenities are currently located in census tracts that qualify and do not qualify for the 30C tax credit based on IRS Notice 2024-20. For existing electric vehicle charging stations, 51% of Level 2 and 60% of Direct Current Fast Charging public stations are located in eligible census tracts. 73% of natural gas, propane, and hydrogen fueling stations are in qualifying census tracts and 75% of biodiesel and renewable fuel stations are in qualifying census tracts. This compares with 73% of existing gas stations in eligible census tracts. For deploying the refueling infrastructure to satisfy future demand, this study shows that truck stops (94%), commercial truck stops (92%), and Federal Highway alternative fuel corridors (89%) are predominantly located in eligible locations. Additionally, significant percentages of the population (62%), light-duty vehicle registrations (64%), and medium- and heavy-duty vehicle registrations (68%) fall within eligible areas.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2024

Quantification of Commercially Planned Battery Component Supply in North America through 2035

There is the potential for rapid growth in battery manufacturing in North America in the coming years, as indicated by investment plans which companies have announced. Argonne National Laboratory is tracking these investment announcements to understand the availability of domestically produced battery cells and battery components over the next decade. We find that companies have made announcements for over 1,300 GWh/year of lithium-ion battery cell production by 2030, enough to conservatively supply ten million electric vehicles and expected growth in stationary grid storage. From 2021 to 2032, battery cell production is modeled to grow 28-fold. For each of the core battery components of lithium-ion batteries (cathodes, anodes, separators, electrolytes, and foils), we describe the current announced capacities for materials with respect to cell production and end-use demand, finding similar rapid growth for each.

25 ENERGY STORAGE↗
DOE OSTI2024

Adoption of Plug-in Electric Vehicles: Local Fuel Use and Greenhouse Gas Emissions Reductions Across the U.S.

The dependence on gasoline-powered light-duty automobiles has made U.S. households vulnerable to the burden of fuel costs. Tailpipe emissions from these vehicles constitute 58% of greenhouse gas (GHG) emissions in the U.S., which are damaging to the environment (EPA, 2023). The adoption of plug-in electric vehicles (PEVs) has been shown to effectively reduce fuel costs and GHG emissions. However, local effects on these benefits are not well understood by American consumers, potentially limiting adoption and therefore the realization of PEV benefits at scale (MacInnis & Krosnick, 2020; EY Americas, 2023). To fill this research gap, this study estimates the fuel cost savings and GHG emission reductions at the state and ZIP code levels by considering local fuel prices, vehicle class preference, average vehicle model year, fuel efficiencies, and driving intensities. The study's findings reveal that the adoption of PEVs can yield substantial benefits in terms of fuel cost savings and GHG emission reductions nationwide. Specifically, driving a battery electric vehicle (BEV) is estimated to result in annual savings of up to $\$2,200$, while driving a plug-in hybrid electric vehicle (PHEV) can lead to savings up to $\$1,500$, when compared to an internal combustion engine vehicle (ICEV) of equivalent size. Moreover, using population-weighted averages by ZIP code, BEVs and PHEVs show the potential to save 400 and 200 grams of carbon dioxide equivalent per mile, respectively, compared to a representative ICEV of the same class. The magnitude of fuel cost savings and emissions reduction vary by region due to various factors. Generally, regions with high gasoline prices, low electricity prices, preferences for larger vehicles, and high driving intensities tend to see relatively large fuel savings. The emissions reductions are more pronounced in areas with clean grids where consumer preferences lie with large vehicles. This regional variability underscores the importance of considering local contextual factors when assessing the potential benefits of PEV adoption. In more than 99% of U.S. ZIP codes, PEVs result in overall savings in fuel use (and subsequent costs) and GHG emissions. While not a central focus of this analysis, reductions in GHG tailpipe emissions from PEV adoption would also come with reductions in criteria pollutant emissions, contributing to improved local air quality depending on the PEV penetration, population density, and electricity generation infrastructure in the locality.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2024

Securing Critical Materials for the U.S. Electric Vehicle Industry: A Landscape Assessment of Domestic and International Supply Chains for Five Key Battery Materials

This study explores the prospective supply of upstream critical materials, providing insights into the U.S.'s capacity to meet its Electric Vehicle (EV) and Energy Storage System (ESS) deployment targets for 2035. It evaluates the proportion of critical materials demand that can be met by domestic upstream sources and the amount that will require non-U.S. sources. The analysis considers geological resources and current international development activities, contributing to the understanding of mineral supply security as the global community strives for net-zero emissions by 2050. The study focuses on five materials assessed in the 2023 DOE Critical Materials Assessment – Lithium, Nickel, Cobalt, Graphite, and Manganese.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2023

Incorporating Social Vulnerability Variables in Measures to Quantify Access to Opportunities

Herein this study quantifies access to travel opportunities to understand what societal factors are linked with local access and to identify communities with reduced access. We introduce a method to compare accessibility across all census tracts in the United States that can be used across geographically diverse communities ranging from sparsely to densely populated areas. This study considers six key opportunities which we consider essential for all communities (grocery stores, public schools, daycares, primary care doctors, pharmacies, and parks), and six additional destinations which can be viewed as a social safety net (homeless shelters, women’s shelters, food pantries, libraries, vocational schools, and banks). We quantify accessibility to these opportunities within a 15 min walk, transit trip, bicycle ride, and automobile drive for every census tract in the United States, and observe a decrease in vehicle miles traveled and vehicle ownership in tracts with increased walkability. Through analysis at the census tract level, this study incorporates variables of social vulnerability with these cumulative opportunity metrics to better understand diminished accessibility as attributed to social and racial inequities. As example findings, we find decreased access to financial services in communities with high minority and limited English speaking populations, no apparent change in access for childcare in communities with high percentages of single-parent families, and potentially increased or decreased access to women’s healthcare resources for Black women depending on the travel mode.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2022

Mitigation of emissions and energy consumption due to light-duty vehicle size increases

Analysts need to consider the shift of light-duty vehicle sales from cars to light trucks to accurately project fuel consumption, greenhouse gas emissions, and consumer spending. Here, we find that energy consumed by on-road light-duty vehicles in the United States can vary by 10% by changing assumptions regarding the sales mix. Scenarios aligned with third-party forecasts, assuming a greater sales proportion of light trucks and fewer cars, yield petroleum consumption 3–8% higher than forecasts from the U.S. Energy Information Administration (EIA), with greenhouse gas emissions 5–7% higher and a 4–9% increase in consumer spending on vehicles and fuel. This incremental energy consumption can be offset by additional technologies for these vehicles. If most sedans were phased out in favor of larger sport utility vehicles, we find a sales share of 30% battery electric vehicles or 39% hybrid electric vehicles would equal the emissions of the EIA Reference Case.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2022

Assessment of Light-Duty Plug-in Electric Vehicles in the United States, 2010 – 2021

The number of plug-in electric vehicles (PEVs) sold in the United States has consistently grown since 2010, reaching 4% of the light-duty vehicle market in 2021. This report examines how the characteristics for these PEVs has changed over this decade, evaluating range, energy efficiency, costs, and performance. Given the vehicle characteristics, this report estimates miles driven, electricity consumption, petroleum reduction, and greenhouse gas emissions attributable to electric vehicles. This report also explores vehicle manufacturing and battery production, considering supply chains from battery cells to assembly. Over 2.1 million PEVs have been sold in the United States through December 2021, with 1.3 million of these all fully-electric battery electric vehicles (BEV), and 800,000 plug-in hybrid electric vehicles (PHEV) which have the capability of using gasoline. The sales-weighted average range for BEVs reached 290 miles in 2021 and 28 miles for PHEVs. We estimate that electric vehicles have driven 68 billion miles on electricity since 2010, thereby reducing national gasoline consumption by 0.54% in 2021 and 2.5 billion gallons cumulatively through 2021. In 2021, PEVs used 6.1 terawatt-hours of electricity to drive 19.1 billion miles, offsetting 700 million gallons of gasoline. We find that this fuel switching reduced consumer fuel costs by $1.3 billion in 2021. Since 2010, 65% of PEVs sold in the United States have been assembled domestically, and over 110 gigawatt-hours of lithium-ion batteries have been installed in vehicles to date.

25 ENERGY STORAGE↗
DOE OSTI2022

Regional Variation in Light-Duty Plug-in Electric Vehicle Emissions

Automobile electrification is viewed as one of the key requirements for deep decarbonization of transportation. However, the exact magnitude of decarbonization from switching from a combustion of petroleum-based fuels to grid-derived electricity is a complex issue. Variations in local grid mixes lead to differing carbon intensities of electricity in different regions. This complexity is compounded by geographical differences in vehicle characteristics. This analysis considers these geographic differences to produce a historical assessment of the fuel-cycle carbon emissions of plug-in electric vehicles (PEVs) in the United States from 2011 to 2021. We find that PEVs in the United States decreased in electricity-derived carbon intensity, from 187 grams per mile to 110 grams per mile from 2011 to 2021 due to improvements in the electric grid and vehicle efficiency. Through 2021, PEVs emitted a total of 13.6 million metric tons of greenhouse gas (GHG) emissions in the United States, including both emissions from electricity and gasoline, while driving a total of 100 billion miles. Of this total, 8.39 million metric tons was due to electricity consumption. Over the same distance, comparable gasoline vehicles would have emitted between 29 and 41 million metric tons of GHG, leading to a reduction of 15 to 27 million metric tons. Relative to national-level assessments that do not factor in this regional difference, these electric vehicles resulted in 13% greater reductions in GHG emissions than previously calculated. In the future, announced goals to further decarbonize the electricity sector will continue to reduce the emissions of PEVs, including reducing emissions rates for vehicles already on the road, further improving the benefits relative to the unchanging emissions of contemporaneous gasoline vehicles.

02 PETROLEUM↗
DOE OSTI2022

Shared Mobility Data Availability and Usage Trends

In this report, we summarize data availability of new shared mobility technologies by mobility type and region and analyze how shared mobility usage varies by time and by demographic factors in the United States. The shared mobility technologies include ridehailing from transportation network companies (TNC), bikeshare, and scooter share. There is a wide range in shared mobility usage per capita across the country, even within urban areas. We observe that there was steady growth of new shared mobility usage from 2015 to early 2020, before COVID-19 reduced overall ridership. An analysis focused on Chicago shows that despite the availability of good public transportation, high usage of new shared mobility modes is centered in high income communities, especially by households who own less vehicles. However, we find that TNC is used for first-mile and last-mile in lower income communities. Analysis on the bikeshare usage also shows that household income is shown to not be a statistically significant factor when accounting for other factors including employment density, population density, percentage of college graduates, and bike-lane proximity.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2022

Vehicle Residual Value Analysis by Powertrain Type and Impacts on Total Cost of Ownership

Vehicle depreciation is a key factor in determining the total cost of vehicle ownership and consumer purchase behavior. This report examines how light-duty-vehicle residual values have evolved over time for conventional and advanced vehicle technologies, accounting for important factors such as market segment, size class, and country of assembly. Advancements in electric vehicle technology have led to plug-in vehicles exhibiting depreciation curves similar to those of conventional vehicles. This report compares two methods for determining depreciation trends (snapshot method and time-series method) in order to identify potential impacts on calculating vehicle total cost of ownership given differing data availability.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2022

Using Mapping Tools to Prioritize Electric Vehicle Charger Benefits to Underserved Communities

Mapping tools can play an important role in incorporating equity into planning, implementing, and evaluating investments in electric vehicle (EV) charging stations, also referred to as EV chargers or electric vehicle supply equipment (EVSE). Federal, state, and local organizations need methodologies for using mapping tools as they pursue equity-focused goals to ensure that the benefits of investments in EV chargers flow to energy and environmental justice (EEJ) underserved communities. This report provides examples of how to apply mapping tools to identify priority locations for installing EV chargers that may benefit EEJ underserved communities through four EV charger planning approaches: corridor charging, community charging, fleet electrification, and diversity in STEM and workforce development. It also explores various methodologies for calculating low-public EVSE density. Ensuring that the benefits of EV charger investments flow to underserved communities involves prioritizing locally identified needs and incorporating community input when choosing charging station locations. Installing EV chargers in a census tract identified as an EEJ underserved community does not inherently mean that those EV chargers provide benefits to residents of that community. In addition, representatives of historically disadvantaged communities or environmental justice communities have concerns that installing EV chargers in their communities could potentially exacerbate or propagate existing inequities. While the methodologies described in this report may help identify priority census tracts for equity-focused EV charger investment, additional community engagement and site evaluation are necessary to determine whether EV chargers are accessible, affordable, and convenient to EEJ underserved community residents and what benefits the local community is looking to realize with EV charger installations. This report is the culmination of many discussions with project leaders from DOE-funded projects deploying EV chargers in communities across the nation, organizations representing EEJ underserved communities, state agencies developing EV investment plans, utilities making major EV investments, and DOE national laboratory experts working in transportation electrification. The authors distributed a draft report for peer review, and reviewer comments are summarized in this report. These methodologies are likely to evolve as more EV charger funding programs are implemented and more real-world data is available to measure the effectiveness of strategies for incorporating equity in EV charger deployment projects. Continued efforts to document best practices and critically evaluate whether equity-focused programs achieve their goals are needed as transportation electrification proceeds at the local, regional, and national levels.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2022

Vehicle Residual Value Analysis by Powertrain Type and Impacts on Total Cost of Ownership

Vehicle depreciation is a key factor in determining the total cost of vehicle ownership and consumer purchase behavior. This report examines how light-duty-vehicle residual values have evolved over time for conventional and advanced vehicle technologies, accounting for important factors such as market segment, size class, and country of assembly. Although plug-in vehicles have historically depreciated faster than conventional vehicles, advancements in electric vehicle technology have led to plug-in vehicles exhibiting depreciation curves similar to those of conventional vehicles. This report compares two methods for determining depreciation trends (snapshot method and time-series method) in order to identify potential impacts on calculating vehicle total cost of ownership given differing data availability.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2021

Domestic Sales Mix of Plug-In Electric Vehicles by Trim Variant and Vehicle Characteristics

As plug-in electric vehicles (PEVs) take up a larger share of the United States vehicle market, their variety increases as well. Since many electric vehicle manufacturers offer multiple PEV trim variants, the distribution of vehicle characteristics such as battery capacity, all-electric range, electricity consumption, and curb weight cannot be determined by sales data alone. Sales data and vehicle registration data were analyzed to quantify and map the trim variant distribution of PEV models from nine automakers. With this information, we quantify national sales-weighted characteristics of fourteen different models over ten years, including battery capacity, fuel economy, and vehicle weight. We find a positive correlation between share of all-wheel drive variants for Tesla vehicles and average annual snowfall, and general uniformity nationwide in other vehicle characteristics. The estimated trim variant distributions will be useful in informing decisions regarding materials recycling and EV impact on the energy grid, and this study found that the total installed battery capacity in PEV in the U.S. was 76 GWh through 2020.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗