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The paper argues that achieving tripled fuel economy requires a systems-optimization approach rather than incremental improvements. It proposes a combination of carbon-fiber composite body-in-white structures, low-drag aerodynamics, and series hybrid-electric propulsion. Modeling suggests that such a 'leapfrog' approach can yield vehicles achieving 80-100+ mpg while maintaining family-sedan utility and safety.

The briefing advocates for the co-design of high-octane fuels and vehicle engines to improve fuel economy and reduce greenhouse gas emissions in the U.S. transportation sector. It highlights the role of ethanol as a cost-effective octane source and details infrastructure progress, such as UL certification for E25 and testing for E30 and E40. The document also identifies eight bio-blendstocks from the DOE's Co-Optima initiative for further evaluation and notes engine testing conducted by Oak Ridge National Lab and industry partners.

The Rocky Mountain Institute (RMI) proposes a comprehensive federal strategy to cut U.S. greenhouse gas emissions and oil use by approximately 50% by 2020. The framework prioritizes reducing energy demand through efficiency in buildings, transport, and industry before substituting supply with renewables and biofuels. Key recommendations include implementing 'feebates' for vehicles, establishing a 'Smart Grid', and creating a national 'energy corps' for workforce training. RMI argues that climate protection is profitable and that the U.S. should move toward a system where all energy production and saving methods compete fairly without distorting subsidies.

The Rocky Mountain Institute (RMI) conducted a life cycle analysis (LCA) using the Argonne National Laboratories' GREET model to evaluate the environmental impacts of the Toyota Prius and the Hummer H3. RMI tested four scenarios, manipulating vehicle lifespan and assembly energy requirements to see if the conclusions of a CNW Research/Marketing report—which claimed the Prius was more harmful to the environment—could be replicated. RMI found that the Prius consistently has a lower environmental impact in terms of greenhouse gas emissions and energy consumption, regardless of whether assembly energy for the Prius was tripled or if the Hummer was assigned a longer lifespan (207,000 miles) compared to the Prius (109,000 miles). The report concludes that vehicle operation dominates emissions due to the Hummer's poor fuel economy, and that the CNW findings diverge significantly from scientifically reviewed work.

The paper proposes a 'hypercar' design based on the synergy of advanced-polymer-composite monocoques, ultralow drag, and hybrid-electric propulsion. It argues that this approach can increase fuel economy by 4–10 times compared to conventional cars, potentially reaching 60–120 km/l with fluid fuels or 250 km/l with fuel cells. The author emphasizes that the primary barriers to adoption are cultural rather than technical, as the industry relies on incremental steel-based design. Strategically, the shift to composites would lower fixed tooling costs, reduce reliance on oil, and enable a transition to distributed energy systems via fuel-cell vehicles acting as power plants.

The document provides technical instructions for using the Demand Branch Properties screen in LEAP to specify the fuel economy of newly purchased vehicles. It details the available units of measurement, the use of lifecycle profiles to account for vehicle aging, and the software's ability to automatically calculate stock average fuel economy based on sales and survival data. It also emphasizes the importance of entering historical fuel economy values to ensure accurate base year stock average calculations.

The document explains the two types of Lifecycle Profiles in LEAP: Aging Profiles, which track how variables like fuel economy change as devices age relative to a new device, and Distribution Profiles, which describe vintage distributions within a stock. It details the software interface for creating, editing, and importing these profiles, including the option to define values via manual data points or an exponential curve formula.

The document details the calculations for transport analysis, focusing on how vehicle stock is tracked by vintage and how fuel economy, mileage, and emissions degrade over a vehicle's lifecycle. It specifies that stock is determined by sales and survival profiles, while energy and pollutant emissions are calculated based on distance traveled and age-related degradation factors.

The 'Fraction of Scrapped Replaced (%)' variable in LEAP determines what proportion of scrapped devices are immediately replaced by new sales, which then affect the stock's energy intensities and emission factors. The default setting is 100%, meaning all scrapped vehicles are replaced, and these replacements are counted separately from the primary 'sales' variable.

The Union of Concerned Scientists reports that SUVs and light trucks in the United States have lower fuel economy and higher fatality rates than cars, contributing to higher consumer costs and increased global warming emissions. To address this, the organization designed the 'UCS Guardian' and 'UCS Guardian XSE' prototypes, which utilize existing technologies—such as unibody frames, improved aerodynamics, and electronic stability control—to increase fuel economy and safety. The report suggests that implementing these technologies across the light truck fleet could significantly reduce U.S. oil consumption and save thousands of lives annually.

The document advocates for immediate action to combat climate change using existing technologies. It identifies fossil fuel combustion and deforestation as the primary drivers of CO2 increase and proposes five 'common sense' solutions: increasing vehicle fuel efficiency, modernizing the electricity system with renewables, improving energy efficiency in buildings, protecting forests, and increasing federal R&D for clean energy. It emphasizes that these steps would reduce emissions while saving consumers money and enhancing energy security.

The Union of Concerned Scientists outlines ten primary ways to lower personal carbon emissions and financial costs, ranging from improving vehicle fuel economy and home energy efficiency to dietary changes and reduced consumption. A final recommendation emphasizes the collective impact of these actions, stating that a 20 percent emission reduction by all Americans could lead to the closure of 200 of the 600 coal plants in the United States.

The Union of Concerned Scientists analysis finds that California's cleaner fuels and vehicle policies—including cap and trade, the low carbon fuel standard, and vehicle standards—will reduce ownership costs for drivers. Weekly savings for new vehicle owners are projected to increase from $3.90 for a 2015 model to $8.98 for a 2025 model compared to a 2008 baseline. A 10-year-old used car purchased in 2025 is estimated to save its driver $7.46 per week compared to a similar used car purchased in 2015.

The document outlines a technical framework for calculating fuel use across various truck types—including tractor-trailers, straight trucks, and cargo vans—using data from the Freight Analysis Framework (FAF) and the Vehicle Inventory and Use Survey (VIUS). It establishes baseline fuel economies (e.g., 5.8 mpg for tractor-trailers) and projects improvements by 2025 based on technology packages such as aerodynamic devices and hybrid-electric powertrains. Additionally, it applies these methodologies to estimate the current fuel use and future savings for the fleets of UPS, FedEx, PepsiCo, The Coca-Cola Company, and Walmart.

The report assesses fuel cell vehicles (FCVs) as a path toward a clean-vehicle future in the US, focusing on hydrogen and methanol as primary fuels. It analyzes the environmental benefits, such as the potential for 'zero-emission vehicles' (ZEVs) when using renewable hydrogen, and compares FCV performance and safety to gasoline vehicles. The document also addresses the infrastructure challenges of hydrogen distribution and the economic value of reducing urban air pollution in cities like Los Angeles and New York City.

The document argues that current NDCs insufficiently address transport emissions, with only 29 countries specifying quantitative targets. It proposes three primary areas for enhancement: accelerating electrification and fuel economy, amplifying 'avoid and shift' measures like public transport and urban planning, and addressing freight emissions through clean fuels and information technology.

The analysis indicates that while existing federal and state tools can achieve significant emissions reductions, they are insufficient to meet the U.S. Copenhagen pledge of a 17 percent reduction below 2005 levels by 2020, or the IPCC's mid-century targets to limit global warming to 2 degrees Celsius. The report highlights the Clean Air Act and Department of Transportation fuel efficiency authority as key federal tools, noting that non-energy emissions reductions can be achieved without increasing energy prices. To reach a 2050 reduction goal of 80 to 95 percent, the report argues that Congress and states must augment existing regulatory tools.

The analysis finds that seven global transport initiatives could reduce global energy-related emissions by 3.7 percent by 2050. The most significant reductions are linked to mode-shifting to rail or public transport, though these require high effort. While electric vehicle and fuel efficiency targets are ambitious, the paper notes gaps in addressing heavy-duty vehicles and total travel demand, suggesting that better policy linkages and wider geographical coverage are needed to improve effectiveness.