Gas Math

I am lucky to live close to where I work. It's not totally luck. I used to live very far from where I worked, and all changes (changing where I live or where I work) since then have reduced this distance. I am also luck to drive a fuel efficient vehicle, a 2006 Volkswagen Passat. There are two ways for me to get from home to work. The first is to take surface streets (Meridian Avenue to Hamilton, in case you want to stalk.) This is a five mile drive, with lots of red lights along the way. My car gets an average of 21 mpg for this trip. The other way I can go is to take freeways (CA-85 and CA-17 for the stalkers.) This is a seven mile trip, but my car gets around 29 mpg. It is also about 5 minutes less time. So which way do I go?

The surface route consumes 0.23 gallons of gasoline. The freeway route consumes 0.24 gallons of gasoline. That's a difference of 0.01 gallons. If I drive this twice a day, 250 times a year, that is 5 gallons of gasoline. So anywhere between $10 to $20 difference, depending on the ever volatile price of gas. It is also an extra 200 miles on my car. Given the way the IRS expenses miles, that is about $242. So let's say it costs me $260/year to take the freeway. But at 5 minutes each way, that is 41+ hours of my time. So is my time worth $6.24/hour? Yeah, I'll take the freeway.