The One Gallon Challenge is a chance for everyone to get a look at some ultra-economical cars which will soon be available to the public--and to see them perform in real-life conditions. These seven cars will travel from Greenfield, MA on Thursday, August 20th, the opening day of Boston Greenfest 2009, to see how they travel the 100 miles to Boston on the energy of one gallon of gasoline.

The cars are light weight, have good aerodynamics, and use very efficient propulsion systems to stretch the energy which fuels them, while at the same time allowing passengers the safety and comfort we insist on. Here is a short description of two of the vehicles:

The Roopod is even slicker and lighter, being built almost entirely of aluminum, by an Industrial Designer from western Massachusetts. See www.roopod.com for details. It is powered by a 2-cylinder diesel engine.

Dirigo, a three-wheeled diesel two passenger vehicle is made in Maine. It recently won its class in the Green Grand Prix, averaging 90 MPG. Can you tell it was designed by boat builders?

Gaia Transport's entry is a single passenger commuter.

Exertrike's "Stealth" is powered by human, electric, and diesel power.

Moonbeam, also made in Maine, is a well-proven 100 MPG around-town vehicle. Moonbeam has been twice to the Altwheels Festival in Boston, but making a 100 mile journey on its own wheels will be a new experience.

A third entry from Maine will be a truck, not a passenger car. The Ricker Truck, is in the process of getting a body.

"EV Jerry" will be competing in his "Spirit of DC", a plug-in Prius Hybrid which has just finished visiting all the state capitals in the lower 48 states.

So, be sure to mark you calendars. Come to Greenfield, Mass. for the send-off at Miles Street Parking lot from 9 am to noon Thursday, August 19; and then see the cars on display at Boston Greenfest, showing just how much energy they consumed getting there. For more information see www.moonbeamplans.com or write jsquibb@myfairpoint.net.