When is 12 mpg better than 100 mpg?

Ian Wright changed the way that I thought about fuel efficiency in motor vehicles. And I suspect that he changed the minds of a few other folks at Foo camp as well.

The math is pretty simple (but totally not obvious if you don't do it). Consider that the average driver travels 12,000 miles per year. If that driver were in a 10 mpg car, they would consume 1,200 gallons of gas. If we could improve the fuel efficiency of his car to 12 mpg, he would consume 1,000 gallons of gas, for a net savings of 200 gallons.

Contrast that to a driver of a modern hybrid. If they were running 50 mpg, they would consume 240 gallons of gas. Improving that number to a lofty 100 mpg would net a savings of only 120 gallons.

The bottom line is that there's not a lot more you can do when you're at 50 mpg, but there's an awful lot that you can do when you're at 10 mpg.

And there are a lot of vehicles right now that come in at near those levels:

Top-selling vehicles in the US in 2006:

1. Ford F-Series pickup (545,963)
2. Chevy Silverado pickup (434,937)
3. Toyota Camry (302,636)
4. Toyota Corolla (274,074)
5. Honda Accord (250,663)
6. Dodge Ram pickup (250,144)
7. Honda Civic (225,212)
8. Chevy Impala (197,304)
9. Chevy cobalt (163,343)
10. Nissan Altima (154,909)

If the goal is to reduce the total number of gallons of gasoline consumed, we need to focus on the problem areas (low mpg vehicles). That's what Ian is trying to do with his startup company: prove that his electric technology is viable in low mpg vehicles where people are willing to pay for performance (aka supercars - his X1 prototype has better performance than any other production car short of a Bugatti Veyron).

Once his technology is proven, then we can see if electric powered pickup trucks would be a viable market.

That's one of the great things about Foo camp: how a serendipitous encounter with someone can change the way you look at the world.

Comments

[Barry Gervin]

Hey that's pretty cool, but with a headline like that, it makes it sound like people shouldn't do anything now and just wait until they can buy a 12mpg vehicle and feel good about it.

In actuality, the math works out even better if you get all of those people driving 25mpg vehicles to buy hybrids at 50mpg. They can do that today without waiting.

In Ontario, the tax rebates lower the difference in price between hybrid & legacy power train to only $1000. You can pay that off in < 2 years of gas savings at todays prices.

[walter Oborski]

The math is correct, but the logic is flawed. While it's true that reducing the fuel consumption on a 12MPG engine will cause it to use less fuel from a percentage perspective, it over looks the initial reality that the 50 MPG engine uses less fuel yearly to begin with. The fact that a high fuel consumption engine can be made to use 200 gallons less of fuel yearly does not erase the initial problem that it uses a much higher volume of fuel yearly than a 50 MPG engine to begin with.