"The average car on the road is about 11 years old, and the average car is driven about 15,000 miles per year. Multiply those figures together and you’ve got a fairly average car with something like 165,000 miles on it"

http://business.time.com/2012/03/20/what-you-only-have-100k-...

And that's AVERAGE of cars still being driven

This is generally incorrect, because if you think about it the cars that died young aren't included in the average. The problem is that there are two averages being cited, and you can't just multiply them to determine a joint average without knowing the nature of the underlying distribution.

Multiplying averages doesn't work for general distributions. (It probably works out mostly alright here.)

Not only is it a math error to multiply it out like that, but it's also wrong to extend the logic to electric cars. Electric cars are likely to have LESS than the AVERAGE CAR total mileage, because (a) they're less useful in places where people need to drive extra-long distances, (b) the batteries get worse and worse at holding a charge over time, just as cellphone batteries do. (c) it's still a rapidly-advancing technology, meaning older models will get obsolete quickly and need to be retired faster than they do with a more mature technology.

> Is this guy serious? The average car is driven 13.5k miles/year. So 50k is 3.7 years.

Did you read the rest of the article?

Quote: "To make matters worse, the batteries in electric cars fade with time, just as they do in a cellphone. Nissan estimates that after five years, the less effective batteries in a typical Leaf bring the range down to 55 miles. As the MIT Technology Review cautioned last year: "Don't Drive Your Nissan Leaf Too Much."

Electric cars have a shorter effective range than "the average car" and due to charging time are less suitable for long trips (or for purchase in places where long trips are the norm) so they're likely to get driven less. And the range gets shorter as time goes on so even if they're comparable in the first year they won't be in later years.

Anyway, the article gave TWO data points. He said "IF a typical electric car is driven 50,000 miles over its lifetime..." gave some conclusions, and then went on to talk about a better-case scenario of the car being driven 90,000 miles. Can you at least accept these as a bracket? The conclusion he reached from considering these two hypothetical data points was that electric cars might be worse than non-electrics in terms of CO2 impact or they might be better, but were unlikely to be a vast improvement and in any case the term "zero emissions" is a misnomer.

When doing a cost-benefit analysis at the end, Lomborgh used his optimistic estimate - 90,000 miles - to conclude that the government would be spending $7,500 in subsidies to save $44 (in the US) or $48 (in Europe) worth of carbon.

Typical miles driven by a car...

Two car household here --

46mo/old Prius - about 52k miles 37mo/old Jetta TDI - about 54k miles

Since we are both solo-commuters, this is fairly typical for the bay area. Probably in the realm measured, but ... a 50k lifetime is a bit of a joke.

My car has almost 70k miles on it, and which means I only have 30k left on the powertrain warranty.