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The document defines electric vehicles (EVs) as cars or trucks powered by electric motors using batteries or fuel cells, distinguishing them from conventional hybrids. It categorizes EVs into battery-electric vehicles, plug-in hybrids, and hydrogen fuel cell vehicles, noting that EVs generally produce fewer greenhouse gas emissions than fossil-fuel vehicles. The guide highlights that battery-electric cars offer the lowest emissions and simplest maintenance, while plug-in hybrids provide a bridge for those with longer trips, and fuel cell vehicles offer fast refueling but suffer from limited infrastructure, particularly in the US.

Hydrogen fuel cell vehicles use hydrogen gas and oxygen to generate electricity for an electric motor, emitting only water and heat. They offer refueling times and driving ranges (200-300 miles) similar to conventional gasoline vehicles, making them suitable for long-distance travel or users without home charging. While hydrogen production can cause pollution, these vehicles can reduce emissions by over 30% compared to gasoline cars, even when using natural gas as a source.

A drivetrain delivers power from a vehicle's engine or motor to its wheels, influencing fuel consumption, mechanical efficiency, and cost. Hybrid vehicles employ three primary drivetrain types: series, where only the electric motor powers the wheels; parallel, where the engine and motor work in tandem; and series/parallel, which combines both methods to optimize efficiency across different speeds. While series/parallel systems offer the best fuel performance, they are more expensive due to the need for larger batteries, generators, and advanced computing.

The 2014 Automaker Rankings by the Union of Concerned Scientists evaluates the environmental performance of the eight best-selling automakers in the U.S. for model year 2013. For the first time since the series began in 2000, all eight analyzed companies reduced their average global warming emissions compared to 1998 levels. Hyundai-Kia is ranked as the 'Greenest Automaker,' unseating Honda, due to fleet-wide improvements in fuel efficiency through engine downsizing and turbocharging. Conversely, Chrysler is identified as the worst performer, earning the 'dirtiest tailpipe' distinction. The report attributes overall industry progress to more stringent federal fuel economy and tailpipe emissions standards, noting an 87 percent drop in smog-forming tailpipe emissions from the U.S. fleet since 1998.

The document examines the strategic importance of rare earth minerals (REMs) for clean technologies and the geopolitical friction caused by China's dominance of their production. It highlights how China's shift toward environmental regulation and energy security has led to export restrictions, triggering WTO disputes with the USA, Japan, and the EU. The author argues that the REM case reveals the inadequacy of current international trade governance in balancing short-term economic priorities with long-term sustainability and resource scarcity.

The document describes how hybrid vehicles combine internal combustion engines with electric motors and batteries to improve fuel efficiency and reduce pollution. It details specific features such as idle-off, regenerative braking, power assist, and electric-only drive, while contrasting plug-in hybrids with battery electric and hydrogen fuel cell vehicles.

The report examines the application of hybrid-electric, battery-electric, fuel cell, and plug-in hybrid technologies in the US trucking sector. It highlights specific use cases, such as urban delivery, port drayage, and auxiliary power units, noting that while medium- and heavy-duty trucks make up only 4% of road vehicles, they account for approximately 20% of transportation fuel consumption. The document argues that expanding electrification is a key strategy for doubling truck fuel efficiency and halving projected US oil consumption over 20 years.

The document examines California's Low Emissions Vehicle (LEV) and Clean Fuels regulation, specifically the ZEV mandate, using the Technology Innovation System (TIS) framework. It details how the mandate evolved from a strict requirement for pure electric vehicles to a more flexible approach that supported the development of Hybrid Electric Vehicles (HEV), Plug-in Hybrid Vehicles (PHEV), and Battery Electric Vehicles (BEVs).

The Union of Concerned Scientists' 2010 rankings identify Honda as the greenest automaker for model year 2008, followed closely by Toyota and Hyundai. The report highlights a significant performance gap between these leaders and the 'Detroit Three' (Ford, General Motors, and Chrysler), who consistently rank at the bottom due to lower fuel economy and higher emissions. While government standards have improved smog-forming emissions across the industry, global warming emissions remain a key differentiator. The analysis also examines the impact of hybrid and flexible-fuel vehicles, noting that while Toyota's Prius significantly improves its overall score, flexible-fuel vehicles often serve as a loophole for automakers to meet fuel economy requirements without providing real-world environmental benefits.

The Union of Concerned Scientists' 2010 Automaker Rankings evaluate eight major car companies using government data from model year 2008. Honda is ranked as the greenest automaker, while Chrysler is identified as the most polluting for the fourth time in ten years. The assessment emphasizes that overall environmental performance depends on cleaning up entire fleets, including high-volume sellers, rather than relying on a few niche green models.

The paper introduces a dual-level agent-based and system dynamics model to evaluate transitions to sustainable mobility. Using UK data, the model indicates that while Hydrogen Fuel Cell Vehicles may dominate in the long term (post-2030), biofuels and ICE-electric hybrids are the primary short-to-medium term alternatives due to existing development and infrastructure compatibility. The findings suggest that technological transitions are more probable than lifestyle change transitions, which require sustained environmental pressure and consumer behavioural shifts.

The document outlines strategies to maximize vehicle fuel economy, categorizing them into vehicle maintenance, driving behavior, and systemic transportation changes. It highlights that proper maintenance, such as using low rolling resistance tires and reducing vehicle weight, can improve mileage. Driving habits, specifically reducing highway speeds and avoiding idling, are identified as key ways to cut fuel use. Finally, it advocates for a transition toward fuel-efficient vehicles, mass transit, and policies that reduce dependence on oil.

The Union of Concerned Scientists' 2007 report ranks eight major automakers on their environmental impact, focusing on smog and global warming pollutants. Honda is named the 'Greenest Automaker' for the fourth consecutive time, though Toyota has closed the gap significantly due to hybrid technology and consistent performance across all vehicle classes. The report highlights a stark contrast between the top performers and the 'Big Three' (Ford, GM, and DaimlerChrysler), with DaimlerChrysler ranking as the dirtiest. Key findings indicate that while smog emissions have improved due to tighter regulations, progress on global warming emissions has been minimal since 1998. The analysis also critiques the use of flexible-fuel vehicles (FFVs) as a regulatory loophole that increases overall emissions and notes that diesel vehicles reduce global warming pollution but significantly increase smog.

The Union of Concerned Scientists' 2007 rankings identify Honda as the 'Greenest Automaker' and DaimlerChrysler as the most polluting based on 2005 emissions data. The analysis evaluates eight companies representing 96 percent of the U.S. vehicle market, using a 50/50 weighting of smog-forming pollutants (NOx and NMOG) and global warming pollutants (CO2-equivalent). While Honda and Toyota lead in consistency across vehicle classes, the report notes that conventional technologies could reduce global warming emissions by 40 percent, and hybrids could offer further reductions.

The text posits that energy efficiency investments are irreversible and more cost-effective than purchasing oil. It highlights the potential for ultralight materials, plug-in hybrids, and biofuels to drastically reduce oil consumption, suggesting that the US could eliminate its oil use by the 2040s at a cost of $15 per barrel. The author emphasizes the role of corporate strategy (e.g., Wal-Mart, Boeing, Ford) and the US Pentagon in driving these technological leaps to enhance economic profitability and national security.

The document reports a decline in US automotive fuel economy from a 1987 peak of 22.1 mpg to approximately 21 mpg in 2005, attributed to increased vehicle weight, horsepower, and the popularity of SUVs and light trucks. It details advanced technologies for efficiency gains, including aerodynamics, low-rolling-resistance tires, hybrid drivetrains, weight reduction, and direct-injection stratified charge (DISC) engines. Additionally, it highlights the impact of basic maintenance—such as tire pressure, air filter replacement, and engine tuning—on fuel economy, and notes that increased efficiency reduces foreign oil dependence and greenhouse gas emissions.

The 2006 School Bus Pollution Report Card by the Union of Concerned Scientists finds that U.S. school buses are among the oldest vehicles on the road, with an average age of nine years, and emit nearly twice as much soot per mile as tractor-trailer trucks. The report grades states on tailpipe soot emissions, smog-forming pollution, and the success of their cleanup programs. While some states like California and Washington have made significant strides in reducing soot through retrofits and cleaner fuels, national soot pollution from school buses has only decreased by more than two percent. The document highlights the vulnerability of children to diesel exhaust, which is linked to asthma and lung growth deficits, and argues that substantial federal and state investment is needed for bus replacement and the installation of particulate traps.

The Rocky Mountain Institute (RMI) outlines immediate strategies to lower U.S. crude oil demand, arguing that a 5% to 9% reduction would remove 1.0 to 1.8 million barrels per day from the global market. Proposed measures include reducing speed limits for non-Class 8 vehicles to 60 MPH, increasing the federal Gross Vehicle Weight Rating (GVWR) for trucks to 110,000 lbs, and mandating Auxiliary Power Units (APUs) for new Class 8 tractors. RMI suggests these actions, combined with increased biofuel procurement and the adoption of 'total-flex' vehicle technology, would restore global excess capacity to 2.5 to 3.8 million barrels per day, thereby reducing price volatility.

The report outlines legislative strategies for U.S. states to increase vehicle efficiency, categorizing them into short-term options—such as HOV lane access for Alternative Fuel Vehicles (AFVs) and Hybrid Electric Vehicles (HEVs), state procurement mandates, and tire labeling—and long-term options, including tax incentives, 'pay-at-the-pump' insurance, and feebate programs. It argues that state action is necessary due to the economic burden of high oil prices, security risks associated with oil dependence, and environmental impacts like carbon dioxide emissions.

The document records a multi-sector call for a U.S. transition to clean energy, arguing that government investment and regulation can simultaneously drive economic growth, reduce oil dependence, and address climate change.