One of the myriad ways I manifest my geekness is that I track my gas mileage. After moving to rural North Carolina I began to notice that the mileage on my 10 year old Honda had improved by roughly 4 mpg to 27 mpg. At first I thought it was the fact that I don’t do much interstate driving anymore. Most of my driving is now on double lane rural roads with 55 mph speed limits, and it’s tough to go much faster with a pickup truck or grandmother in front of you. 80 mph on multilane interstates is a thing of the past.
The answer came a couple of weeks ago at the gas pump. Most of the gas stations do not offer gasohol whereas in the Philadelphia area E10 - or 10% ethanol – is the norm. I’m a big supporter of ethanol, especially the cellulosic kind, but being also a math geek I thought I would take the opportunity to figure out how much using E10 had cost me over the past 5 years.
I drive roughly 20,000 miles a year. Let’s assume that the average price per gallon of gasoline during the past 5 years was $2.75/gallon.
So had I driven 100,000 miles on pure gasoline at 27 mpg I would have needed a smidge over 3,700 gallons and spent $10,186 on gasoline during that 5 year period. On E10 at 23 mpg I actually used 4,350 gallons of fuel and spent $11,963.
So over a five year period I paid almost $1800 more in fuel using E10 than I would have using pure gasoline. That’s about $1/day more in fuel costs.
E10 is mandated in the Philadelphia area by clean air laws. Is it worth it? Since I make more than the average I can afford the additional cost, so it’s worth it to me. However for many others who drive 20,000 miles the additional $350+ dollars a year is an unnecessary burden.