Is buying a used car greener than buying a new hybrid?

Reduce, Reuse, Recycle. One aspect of energy use that's often overlooked when comparing cars is the total lifecycle consumption. Buying a new hybrid vehicle compared to a similar sized vehicle with a conventional powertrain can certainly help you reduce. However, it takes a lot of energy to to build a car. Creating a Prius consumes 113 million BTUs of energy. Similarly, energy is required to dispose of a used car. However, those are one-time uses of energy. Fuel consumption is an ongoing variable cost. The production and disposable energy must be spread over the life of the car. The longer a car is in service, the fewer number of production and disposal BTUs per mile. This is where Reuse comes into play. Factoring in all this energy use it may actually be better to buy a higher mileage used car than a brand new hybrid. By keeping an existing car in service that has slightly lower efficiency than a brand new one the net energy use could still be lower. However, the equation is not even as simple as all that. A ten year old car that gets 30-40mpg may actually pollute a lot more than a new car. Emissions standards have tightened over the years. And, as a car wears, the emissions typically get worse. If you choose to go for a used car, make sure it has been well maintained and that the emissions control equipment is in proper working order.