How much energy does it take to conceive, design, build, market, transport, sell, "recycle" and register a new car? Why is this not taken into account when calculating a new car's impact on the earth vs. keeping a older car? I'm thinking that a new hybrid will last the average of all cars in the usa- 172K. My last wagon had over 300K. Let's say my current wagon will last to 344K. Help me figure how much impact I save by NOT buying a new car.