Electric vehicles create pollution through electricity generation, but are they still better than gas vehicles?

Electric cars pose as zero emissions vehicles, but this is not the case. Electric vehicles aren’t powered by oil but they require electricity, and when it comes to carbon dioxide emissions electricity generation surpasses even transportation. So how does the impact of an electric vehicle really compare to that of a gas powered vehicle? We can use a basic emissions calculation to compare the two.

As an example, let’s compare the Tesla Roadster (electric) to the Toyota Prius (gas electric hybrid). Emissions from the Prius result from gas being burned in the car’s engine. In contrast, emissions from the Roadster happen before the car plugs in to charge - the process of creating that electricity also creates emissions. The Roadster can travel 245 miles per charge. One charge would take about 76 kwh (kilowatt hours) of electricity. The EPA’s eGrid found that this would equal 140 pounds of CO₂ in Wisconsin. The 2010 Prius gets 50 miles per gallon, so travelling 245 miles would require 5 gallons of gas. The EPA calculates this would release 98 pounds of CO₂. In this example, the hybrid beats the electric car. A car getting 34 miles per gallon would be comparable to the electric car, emitting 141 pounds of CO₂ when travelling 245 miles.

When considering the impact of electricity use, location is crucial. The EPA illustrates that each region has a different electricity profile (follow this link to find one for your area), depending upon the electricity sources used by the power provider. Madison, Wisconsin gets 68 percent of its electricity from coal, but in Sacramento, California only 12 percent comes from coal. While a Tesla Roadster electric car charged in Madison would release 140 pounds of CO₂, the same car would only release 55 pounds of CO₂ when charged in Sacramento.

CO₂ is not the only factor to consider when comparing emissions. NOx and SO₂ gasses, for example, are the main causes of acid rain, and vehicles are the primary culprit of NOx gas production. When it comes to NOx, electric cars trump gas cars. Electric vehicles could also play a key role in reducing smog, since it is primarily formed by vehicle emissions.  On the other hand the main source of SO₂ is electricity, and while current transportation creates almost no SO₂ emissions, increased reliance on electric vehicles would change that. Energy use poses a complex problem, and the solution isn’t as easy as “electricity” instead of “gasoline.”

Depending upon the location the vehicle is charged, electric vehicles may or may not be more environmentally friendly than a gas powered vehicle with good gas mileage. Neither hybrids nor current electric vehicles offer a sustainable option. The sustainability of the electric vehicle depends on power companies moving away from greenhouse gas-producing energy sources and on to renewable energy. Though the transition to renewable energy has been slow in America, “real” zero emissions vehicles may not be that far into the future. Companies in Japan are testing an electric car powered by the sun. Instead of going to gas stations, cars would refuel at solar stations. That’s a bright idea for a more sustainable future.

To learn more about emissions reduction go to cleanerandgreener.org

Written by :

Laura Green