I've recently seen a spate of articles on how the real world calculations on mpg from the EPA is reflecting poorly on hybrid cars. (List of the new EPA MPG for Hybrid Cars) There's been everything from the "See, See!, I told you hybrids are a scam!" to conspiracy theories on how Toyota was trying to game the system, while Ford wasn't.
The Truth About The Change in the EPA
The truth is less fuel efficient cars are the ones that should be suffering the most from the consumers viewpoint. You see, it's a problem of scale. For instance, let's look at a reduction of 20% in the mpg ratings. 20% means different things depending on where you are on the scale.
Why? Let's look at the numbers.
Hypothetical Car vs the Prius
Let's assume your car has gone from 20 mpg to 16 mpg according to the EPA. If you drive 15,000 miles a year, you will need 188 more gallons a year to fuel your car. And at the current price of $3/gallon (if you're lucky), that's a difference of $562.50. The Prius rating has gone from 60 to 48 mpg (highway mpg). Which means you will need to buy only 63 more gallons per year. At current prices that's $187.50 dollars a year over 15,000.
Another way of looking at it: If your tank holds 15 gallons, you will need to fill up 12.5 more times. If you drove the Prius, you would only need to stop 4.2 more times. :-)
Clearly the difference in mpg for the Prius is less significant than for the hypothetical vehicle getting 20 mpg.
You might point out, quite legitimately, that most cars had their ratings dropped 8 to 30%, and here I'm using 20%. Aside: The Prius went from 60 to 48 mpg highway, which is why I chose those numbers. If you run the numbers for a gas only car that went from 20 mpg to 18 mpg, a 10% change, that's an added fuel cost of $250 a year. The Prius is still winning out.
Next Time You Shop For a New Car
You might want to keep this in mind the next time you buy a car. Let's say you're trying to decide between a car that gets 15 mpg and 20 mpg. That's a huge change. You will save 250 gallons ($750) a year. But if you are trying to decide between a car that gets 45 and 50 mpg, that's a difference of only 33 gallons (or $100) a year.
|MPG||+5||Gallons Saved/ 15K Miles||Fuel Savings ($3/Gallon)||Over 5 Years|
|35||40||54||$ 160.71||$ 803.57|
|40||45||42||$ 125.00||$ 625.00|
|45||50||33||$ 100.00||$ 500.00|
|50||55||27||$ 81.82||$ 409.09|
|55||60||23||$ 68.18||$ 340.91|