The German equivalent of AAA — Allgemeiner Deutscher Automobil-Club, or ADAC — just finished an exhaustive test of almost all cars available for sale in Europe (241 to be exact) in real-world conditions to answer one question: which car can travel the farthest on €30 (~$36 US) worth of cash?
In the end, the Fiat Panda Natural Power — a dual fuel CNG/gasoline-powered vehicle — won hands down by traveling 724 kilometers (~450 miles) on €30 worth of CNG. If you do the calculations, that’s 8 cents a mile, which may sound kind of average to U.S. green car sensibilities, but consider that in Germany gasoline costs about $6.20 per gallon — meaning that even a 30 mpg car would cost about 21 cents per mile to drive there. At $3 per gallon gas, that same 30 mpg car will cost you 10 cents a mile in the U.S.
Even though all the press releases I read on the topic were rather cagey about what the average fuel efficiency of the Panda was during the tests, I did a few back calculations to figure it out myself. ADAC used an average price of €0.94 per kg for the CNG calculations (as shown in the above picture), which means that they obtained a fuel efficiency of 22.7 km (14.1 miles) per kg of CNG, seeing as they traveled 724 km on €30 of fuel.
In the US, CNG is sold in units of gasoline gallon equivalents (gge) instead of kilograms, but using this handy calculator, I was able to figure out that the current average U.S. price of $1.90 per gge is equivalent to €0.62 per kg — roughly 65% of the cost of the €0.94 used by ADAC in their tests. So in the U.S., the same Fiat Panda Natural Power would go 450 miles on about $23 of CNG — or about 5 cents per mile, the equivalent of a 60 mpg car at $3 per gallon gas in the US..
Given that the Fiat Panda Natural Power starts at about €14,000 (~$16,700), if what you’re after is pure economy and you live in Europe, that sounds like a steal.