Schadenfreude - Prius numbers

From Gas 2.0:

Porsche Panamera Emits Less CO2 Per Horsepower Than the Prius
When you�re on top, people will always try to take you down. Since the Prius is one of the most fuel efficient cars in the world, it makes for some interesting comparisons, like the Porsche Panamera S Hybrid emitting less CO2-per-horsepower than the Prius.

Horsepower-per-liter is often a measure of a vehicles performance efficiency. Many automakers clamor to make the magic 100 horsepower-per-liter. The Porsche Panamera S Hybrid, with its 333 horsepower supercharged 3.0 liter engine combined with the 47 horsepower electric motor actually makes a very impressive 125 horsepower per liter. And it still manages to get around 34.5 mpg. Can�t complain about that.

In terms of actual emissions, the Panamera puts out 159 grams of CO2 per kilometer whereas the Prius puts out about 89 grams of CO2 per kilometer. For comparision, the Chevy Volt puts out around 130 grams of CO2 per kilometer. Meanwhile, a Ferrari 599 GTB Fiorana 415 grams per kilometer from its 6.0 liter V12 engine. Getting a better picture? So the Prius is without a doubt the cleaner car.

Members the the Autocar Forum, however, are measuring the performance of its Panamera Hybrid on another scale; grams of CO2-per-horsepower. It is an interesting measure of performance and green cred, and if you do the math (380 hp/159 g/CO2) the Panamera makes 2.4 horsepower per gram of CO2 per kilometer. The Prius�s 1.8 liter 98 horsepower engine coupled with its 36 horsepower electric motor makes for a total of 134 horsepower, or 1.5 horsepower per gram of CO2. Interesting.

It�s a neat way to poke at the Prius and in fairness, it is a sign of the efficiency of the engine if you can make more horsepower with fewer emissions. Then again, CO2 is just one measure of engine emissions, and I doubt anybody is going to trade in their Prius for a Panamera Hybrid after reading this. But as a different measure of engine efficiency, I thought this was neat. I always liked comparing horsepower numbers of muscle cars, so why not horsepower per CO2?

An interesting and perfectly valid metric. Cool!