Well the short answer is yes, while the long answer is a little more uncertain. If an electric vehicle is charged with green power, such as wind turbines or solar panels, then there are zero emissions in the running of an electric vehicle. That would be in a perfect world though, but if you look at the sources of electrcitiy in the US in 2005, then it is seen that only 9.4% of their electricity is generated by green sources, being hydroelectric, solar and wind.

So with only 9.4% of electricity generated in the United States being green, then there are still plenty of emissions used in the charging of these electric vehicles batteries. If we look at all the different model vehicles from before and check out the carbon emissions being emitted from the running of these vehicles, we can see just how much environmentally friendly these electric vehicles are.

The Toyota Corolla produces 173g/km of CO₂6 emissions from the combustion of the petrol to run the vehicle, while the Toyota Prius produces only 106 g/km of CO₂7 emissions to run the petrol electric hybrid engine. With the Honda FCX Hydrogen Fuel Cell vehicle, we know that it takes 32kwh to convert enough hydrogen to run the vehicle for 45km, which works out to 0.711kwh/km. As coal is the largest source of energy, we will use that as an example to show how much carbon emissions are generated by the burning of the coal to generate enough electricity to power the battery enough to drive for one kilometre.

Coal power plants are said to achieve 2kwh per kg of coal burned, so to convert the half a kilogram of hydrogen needed to run the vehicle for 45km, which requires 32kwh, then it would take 16kg of coal to be burnt. As each kg of coal burnt produces 0.915 kg(CO2) / kWh, then the 16kg of coal would produce 14.64kg CO2

The Burning of 16kg of coal to produce the 32kwh of power to convert the half a kilogram of hydrogen to run the Honda FCX for 45 kilometres theoretically (if coal power plants were used to produce the power) pollute 325g of carbon emissions into the atmosphere per km travelled.

The Tesla Roadster requires only power to charge the batteries, instead of trying to convert hydrogen and the such. A charge of the Tesla’s batteries to drive the vehicle 161km requires 31kwh of electricty. We shall use the same example of burning coal to show emissions per km as it is the largest source of electricity in the United States.

These calculations show that the Tesla roadster, by charging using conventional coal burning electricty, only emits 88g of CO2 emissions per km driven. As you can see in the graph below, the Tesla Roadster (electric vehicle) is the most environmentally friendly when using coal burning electricity to power the vehicles batteries.

As the above calculations and graph has shown that if the electrically dependent Tesla Roadster were charged using dirty coal burning methods, then it would still be much cleaner than running any of the other vehicles on fossil fuels. As the future of green energy looks at providing homes and industry with cleaner electrcity, then zero emissions from electric vehicles is quite achievable.