One Gallon Challenge: 164 MPGe

Last week, the Porsche participated in the One Gallon Challenge, part of Boston Greenfest 2009. We traveled from Greenfield, MA to Boston City Plaza using 23 kWh of battery power, equivalent energy to 0.65 gallons of regular ethanol-containing gasoline. That translated to 164 miles per gallon equivalent (MPGe). Here is a link to our path. We also got lost on the way which added a detour, so the total length of the trip was 118 miles.

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Both in Greenfield and in Boston, we had a tent for the car and a lot of visitors. Outreach and public education is an important part of our effort. For everyone who stopped by to see our car last week, thank you.




A day before the race, we drove from Cambridge, MA to Greenfield, MA. We completed this drive on a single charge during the prior night. In Greenfield, MA we charged using 240V AC at Ford of Greenfield which generously let us park there at night.


However, we were not able to fully charge during night due to logistical difficulties, so we started the race with 80% full batteries. We had to recharge on the way. Luckily, Colonial Dodge of Hudson, MA let us park next to their service bays during the day and fill up our battery.

Charging at Colonial Dodge

We also had two cars, a hybrid-electric Toyota Prius and conventional Pontiac Grand Prix which drove with the Porsche. We took the chance to compare the vehicles against each other considering all three cars drove together along the same route.


Toyota Prius ran the race at very respectable 52.9 mpg, while the Pontiac Grand Prix did 22.8 mpg, fairly typical for a midsize sedan. We observed that fuel economy measured in mpg is not as telling as fuel consumption, usually measured in gallons per 100 miles or in liters per 100 kilometers, a European metric. You can readily see a difference between equivalent fuel consumption of an electric, a hybrid and a conventional car on this plot.

More updates are coming about our recharging experience and about our greenhouse gas footprint.

Update: There was quite a bit of press coverage for this event.
One Gallon Challenge: alt-fuel "race" cars get up to 164 MPGe