Does driving a hybrid vehicle really help you become green?

Unless you live in one of the major US cities with sufficient public transport (New York, Chicago, LA), living in the United States unfortunately comes with the requirement of owning a car. When the day comes to buy a new car, I want to make the most environmentally informed purchase on which car I purchase. Certainly more eco-friendly cars such as hybrids and electric vehicles will be in the mix.

Hybrid and electric vehicles are all the rage these days due to the ‘greener’ image they portray. These cars are marketed as eco-vehicles but do they really reduce emissions compared to more conventional vehicles? The short answer is yes.

Does driving this really make me green?

Does driving this really make me green? photo from hybridcars.com

Critics (coming largely from the US auto industry) of eco-friendly vehicles argue that the energy used in the advanced technologies required to make a hybrid or electric vehicle end up harming the environment relative to conventional automobiles. Critics are partially correct in pointing out that the manufacturing process and materials used to make advanced batteries in eco-friendly cars drive up the energetic cost of production. However, the energy used to make a car accounts for anywhere between 5-20% of the total energy of an automobile from cradle to grave. That means between 80-95% of the energy used by a car over its lifetime comes from fossil fuels burned while driving the vehicle. More fuel-efficient vehicles more than compensate for the increased manufacturing energy costs through reduced energy consumption during day-to-day driving.

That said, owning an eco-friendly car doesn’t necessarily make you ‘green’. At the end of the day hybrids still run on fossil fuels and emit harmful greenhouse gases. Driving patterns such as urban vs. highway driving or driving aggressively as opposed to defensively can greatly reduce the efficiency of hybrid cars. In addition, driving a hybrid still uses much higher amounts of fuel and releases more emissions than public transport (excluding airplanes) or walking/biking.

Pure electric vehicles do not directly emit greenhouse gases but do so indirectly because they are running on electricity produced from a fossil fuel based power plant somewhere (assuming that the household is not run exclusively on solar or wind derived energy sources). In the US, much of the electricity delivered to households is generated by coal burning power plants. If an electric vehicle is charged with only electricity derived from coal-burning sources, the emissions cost of operating the electric vehicle is on par with a conventional automobile, or in some cases even worse

Where does the electricity come from to power your electric 'green' car? Photo from bbc.co.uk

Where does the electricity come from to power your electric ‘green’ car? Photo from bbc.co.uk

How often you replace your car can also greatly offset any eco-efficiency advantages of driving a hybrid or electric vehicle. One study based on European Union countries recommends changing cars only at 20-year intervals in order to justify the amount of energy used to manufacture a new hybrid vehicle. Some of this cost is obviously offset if you are einstein-bikepurchasing a used car but the cost of manufacturing a car cannot be ignored.

The moral of the story for me is that when I buy my next car I should look at hybrids and
choose a car I can drive for the next few decades. Or I could simply move to a place that doesn’t require a car and be more like this guy.

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