Does a Prius make $ense: part II

My post last week about whether it makes financial sense to buy a Prius, which costs more but gets about 45 mpg, generated some heated debate. I crunched the numbers and concluded that the environmentally-friendly car was unkind to the wallet.

But it got me thinking. How many miles to the gallon would a car have to get to make dollars and cents? The Toyota Prius is very popular, especially among greenies, but what would it take to achieve mass popularity?

Listen up, Asia. (Detroit has its ears plugged.) Create an affordable, NOT-gas-thirsty camel car that paid off in five years - unlike the 11 it takes with a Prius - and everyone and their mother will line up to charge one.

There are three ways to achieve achieve camel car cult status. Raise the mpg considerably, lower the price considerably, or find a happy balance between the two.

The first scenario gets ugly quick. Driving 12,000 miles a year, a car that gets 200 miles to the gallon would cost $300 to fill up each year at $5 per gallon. Whoppee!

But if this camel car costs $8,900 more than a new 2008 Civic, as the Prius does, it still takes 5.2 years to pay off the higher sticker price. Each year after that you save $1,700 a year in gas. (The Civic, at an average of 30 mpg, costs $2,000 a year to fill up if you drive 12,000 miles.)

If the camel car only cost only $3,000 more to buy and got 45 mpg, you save about $700 a year on gas, bringing the payoff point to 4.3 years. But who would sell a camel car that cheap?

A balance between higher mpg and lower sticker price would do the trick. A camel car that costs $5,000 more to buy and gets 60 mpg would payoff in five years. Because at 60 mpg you save $1,000 a year on gas compared to the Civic.

Okay I've done the math. Now who is going to make my camel car?