Cars Emissions and Global Warming
Earth is warming because of global warming pollution, and transportation-related sources are a major contributor.
In fact, the U.S. transportation sector alone emits more carbon emissions than all but three other countries' total emissions. Sixty percent of these emissions come from cars and trucks (the rest come primarily from heavy-duty vehicles and airplanes).
Three factors contribute to carbon emissions from cars and trucks:
- The amount of fuel used (measured by fuel efficiency)
- The amount of carbon emissions released when a particular fuel is consumed (how "clean" the fuel is)
- The number of vehicle miles traveled
Increasing fuel efficiency
The amount of fuel consumed by cars and trucks governs how much global warming pollution enters the atmosphere: the more gasoline burned, the more pollution released.
Because of this, increasing fuel efficiency is a cost-effective and technologically feasible method to address the threat of global warming.
In August 2012, the federal government enacted strong new standards for vehicles produced through 2025. If correctly implemented, these standards could nearly double the average new vehicle fuel economy to about 50 miles per gallon.
Still, state and national policies could and should do more—a cleaner future depends on it.
Learn more about fuel efficiency>
Using cleaner fuels
So long as fuels are sourced from dirty sources like oil, fuel efficiency will only decrease carbon pollution so much: large-scale carbon savings require a shift to cleaner fuels.
Cleaner fuels can be produced from organic matter like corn, grasses, vegetable oil, agricultural waste, and even garbage. Such fuels hold great potential as an oil and climate solution—but their environmental benefits vary depending on how they're made and what they're made from.
Learn more about clean fuels>
Because energy from the electric grid tends to be cleaner than gasoline, cars that use electricity emit less global warming pollution than gasoline-burning cars.
In fact, cars that rely entirely on electricity (battery-electric vehicles, or "BEVs"), emit on average less than half the global warming pollution of their gasoline-burning counterparts—and cost less to fuel.
Learn more about electric vehicles>
With the number of cars on the road expected to double, gains in fuel efficiency and cleaner fuels will not necessarily reduce global warming pollution. We need to drive less.
Policies that reduce the number of miles driven by cars and trucks also tend to improve the quality of life and protect natural resources. These policies—often called "smart growth"—emphasize livability, mixed-use development, and transportation alternatives.
Learn more about smart growth>