Transportation accounts for nearly a third of greenhouse gas (GHG) emissions in the US (second to electricity), according to the U.S. Environmental Protection Agency (EPA). Studies show anywhere from 25-50 percent of toxic air emissions come from motor vehicles.

It’s increasingly clear that vehicle emissions have a large impact personal and environmental health. Enter the electric car–or rather, its PR department. Although the electric car (EV) has been around since the 1800s, the past decade has seen a huge surge in both production and support of cars that buzz as well as beep.

This Earth Day, we explore how EVs and current initiatives toward improving vehicle efficiency are driving change to a greener world.

EVs Reduce Emissions

EV manufacturers could have no better representative than the environmental and government agencies currently pushing for development of technology focused on reducing carbon dioxide and other toxic chemical emissions from cars.

GHG emissions have steadily increased over the last twenty-five years, in large part due to the increased demands of travel, urban sprawl, population and economic growth, cheap gas prices (in the 1990s), and limited gains in fuel efficiency research and production.

In 2009, the Environmental Protection Agency released clear “endangerment findings,” that the current and projected concentrations of six GHG emitted in combination from new motor vehicles and engines could reasonably be anticipated to threaten the public health and welfare of current and future generations.

Any Way You Run It

Electric cars cover a range of vehicles powered by stored energy, mainly those which use a rechargeable battery. They have been shown to be more efficient at converting stored energy for driving and do not use energy while idling, a main source of wasted heat and energy in conventional vehicles. EVs can also re-capture energy through regenerative braking, converting the car’s kinetic energy into electricity that charges the battery.

Cars that run solely on battery power, called pure electrics, have no tailpipe. This literally easy-to-see fact is highly lauded when with regard to their environmental impact. Because they don’t emit any pollutants into the air when driven, they “obviously” have an emissions advantages over conventional gas-powered vehicles. Powered only by an electric motor, pure EVs have distance and speed limitations that concern some drivers, especially as public-use charging stations have yet to be widely installed across the country.

Diagram of a hybrid electric vehicle (HEV)
Diagram of a Hybrid Electric Vehicle (energy.gov).

Hybrid Electric Vehicles (HEV), designed for fuel economy, utilize an internal combustion engine (ICE) to charge the car’s electric propulsion system, the battery. The don’t need to be “pluged in” to regain charge. Although these HEVs are ultimately powered by gasoline, they are still more fuel-efficient and less wasteful than conventional vehicles. In HEV, the kinetic energy produced by the ICE that would normally be wasted is recaptured and used to run the vehicle. Also, a HEVs ICE is generally smaller and the ICE usually shuts off while idling, reducing waste-heat as well.

Plug-In Hybrids (PHEV) provide an alternative for drivers who prefer to go electric, but are nervous about the risk of running out of charge while on the road. PHEVs have both an electric motor and a supplementary internal combustion engine that kicks in once the battery is depleted, extending driving range. PHEVs ability to run in gas or charge eliminates the range concern with pure EVs, and PHEVs have a more powerful electrical system than HEVs and thus can travel on electricity longer.

While PHEVs demonstrate significant reductions in GHG emissions, they may represent an additional significant benefit for the environment. Some advocates feel PHEVs are the ideal technology to help transition our infrastructure dependence to electricity, as PHEV-technology-adoption wouldn’t necessitate the broader changes and construction (for example, charging stations) all-electric transportation system would require.

Beyond Emissions

In talking about the environmental impact of electronic vehicles, it is important to consider what’s at the other end of the wire. Electricity is actually the number one cause of U.S. GHG emissions, because the sources we use to produce it can range from very clean to very high-polluting. Powering a car with electricity produced by solar or wind power is extremely environmentally friendly, while powering a car with electricity produced from burning coal may actually have a worse impact on the environment.

Remember to consider what's at the other end of the plug (energy.gov)
Remember to consider what’s at the other end of the plug (energy.gov)

Although concerns about the production and source of energy used to produce and run EVs are important when considering emissions impact, there is further research to support their environmental benefit. EVs still achieve better fuel economy and lower fuel costs than similar ICE vehicles, even when the energy is produced by fossil fuels. Conventional, gasoline-powered ICE use as little as 15 percent of fuel energy to power the vehicle. EVs demonstrate an average of 80 percent efficiency, and much of the waste-heat generated can be used to heat the car.

Additionally, a study published in “Scientific Reports,” March 2015, found that EVs mitigate two other wellness impacts. Because EVs emit less heat, they don’t contribute to overall temperature increase in summer, unlike ICE cars.  First, this can reduce the “heat island effect,” the increase of heat and heat-related heath issues in urban areas due to human activities, such as driving. Second, it can reduce the need for energy consumption in air conditioners, further reducing energy consumption.

Government Actions

The U.S. Vehicle Technologies Office is a major player in the advocacy of EVs for environmental improvement. VTO is aggressively perusing adoption and research of highway transportation technologies to improve overall vehicle fuel economy and reduce emissions, supporting the advancement of vehicles with greater efficiency and less toxic emissions.

In 1970, the Clean Air Act began a major shift in the federal government’s role in air pollution control. A major component was the recognition of the importance of cleaner fuels to reduce car emissions. Cars purchased today are more than 90 percent cleaner than those purchased in 1970.

Then the scary 2009 EPA endangerment findings supported the necessity of more aggressive research at the federal level for approaches such as low GHG fuels and improving fuel efficiency, in addition to implementing stronger standards for GHG emissions in new vehicles and engines.

A 2014 study from the University of Minnesota comparing ten alternative fuels confirms that EVs powered by coal and ethanol have a detritus effect on the environment. The study reinforced, however, previous findings that the impact of bad air-quality on individual health was of equal or greater concern than the impact of GHG on the environment.

VTO’s Clean Cities program aims to reduce US dependence on petroleum for transportation to improve the country’s economic and environmental security by 2.5 billion gallons a year in 2025. In addition to programs support research and development of EVs, more than a dozen alternative fuels are in production or under development.

What You Can Do

It’s not all altruistic. In addition to research and lawmaking, the VTO is dangling the proverbial carrot to get consumers charged up about efficiency and the environment. Consumers considering taking up the plug can get a tax credit from the VTO for new qualified, plug-in electric vehicles. And finally, it’s estimated that widespread adoption of electric vehicles would halve our personal fuel consumption, which means huge savings every day at the pump as well.

Compare the costs of driving with electricity at energy.gov.
Compare the costs of driving with electricity at energy.gov.

Driving an EV, HEV, or PHEV is just one way you can help improve personal and environmental well-being through transportation changes. Factors addressed by EV which affect the environment, idling, braking, and acceleration, can also be mitigated by small changes in your behavior. Go easy on the pedals and avoid idling for longer than 30 seconds. Reducing what you keep in and on your car (extra weight) and getting regular maintenance will improve fuel economy and reduce the amount of emissions any car produces.

This Earth Day, gaze out over the highway, take a deep breath, and take comfort in this forecast. While you’re coughing up that lungful of smog, know that improvements to the air and environment are not just down the road, they’re driving by, in production, on the government’s agenda, and at your local dealership.