What is the record mpg for a car?

Answer 1

To answer this question, you must first define the meaning of the word "car". If you use the loosest definition, then I believe the following answers the question.

In the mid-nineteen eighties, the Guinness Book of World Records' record was held by an experimental Mercedes Benz, that if I recall correctly, used a single cylinder engine of about 49cc that was cycled on and off at full throttle so the "car" vacillated between about 25 and 30 mph. (Contrary to popular belief, internal combustion engines are most fuel efficient at WOT (wide open throttle) because the point of greatest inefficiency in the case of a gasoline engine is the pressure drop across the throttle plate (which is at a minimum at WOT), next followed by the friction (drag) of the piston and piston rings. This latter point explains why, excluding extraordinary circumstances, vehicles with fewer cylinders (less piston/ring drag) exhibit greater fuel efficiency than the same vehicle with more cylinders.) The experimental Mercedes "car" had two wheels, fore and aft (similar to a motorcycle) and two wheels side by side (similar to "training wheels" on a bicycle). Once in motion, the "training wheels" would retract like the landing gear on an aircraft. The body of the car was completely streamlined, and resembled a fiberglass torpedo with a sizable vertical aerodynamic stabilizer in the rear. Using this configuration, Mercedes, as documented by the Guinness Book of World Records, was able to extract 2,400+ miles out of one gallon of gasoline (yes, 2,400 MPG).

Very soon after this, another competitor, and I do not remember the brand, beat Mercedes with a similar design, at somewhere around 2,700+ mpg. Mercedes, always wanting to be known as The Best, quickly threw more money at the program, and improved their design to attain over 3,000 MPG.

I was unable to find information on any additional work that has been done, subsequent to the completion of the above work.

As I said, the above record takes a special interpretation of the word "car", but it is nevertheless a useful study in that it does show what manufacturers are capable of if they are allowed to pursue the goal of highest mpg without any restrictions, most notably EPA emissions and DOT safety requirements.

- George

McLean, VA

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Shell Oil company has been hosting a yearly competition since 1939 called the "Eco Marathon." Surprisingly, they give very little press release to this event, and even their web site has limited information on this event. According to Shell, the current record holders are:

The current Prototype Internal combustion-engine record was set in 2004 by the team from Lycée La Joliverie (France), whose car ran the equivalent of 3,410km on a single litre of fuel.

The current Prototype Fuel Cell record was set in 2005 when the hydrogen-powered vehicle built by ETH Zurich (Switzerland) ran the equivalent of 3,836km on a single litre of fuel.

The current UrbanConcept combustion engine record was set in 2008 by the Luleå University of Technology, Sweden driving 299 km/l and the UrbanConcept Fuel Cell record was set by De Haagse Hogeschool (Netherlands) whose car ran the equivalent of 848km on a single litre of fuel.

The climate-friendly Grand Prize given to the team that produces the fewest CO2 emissions from wellto wheel was set by the Luleå University of Technology, Sweden with the equivalent of just 6.15 grammes per kilometer. (6.15g/km)

The five standing records established during the event were (previous records follow in parentheses):

Microjoule, St Joseph La Joliverie, 3,771km/l (3,582km/l 2009; 3,410km/l 2005), IC Prototype

Solar Car Solutions, Lycée Louis Pasquet, 665km/Kwh (644km/Kwh 2009, 570km/Kwh 2008), Solar

Team NTNU, Norges Tekiske og Naturvitenskapelige Universitet, Norway, 1,246km/l, best overall UrbanConcept fuel consumption (848km/l 2008)

FL Smith Roadrunners, Technical University of Denmark, 589km/l in an internal combustion UrbanConcept (306km/l 2007)

Team NTNU, Norges Tekiske og Naturvitenskapelige Universitet, 2.6g/km, lowest CO2 emissions for UrbanConcept (6.15g/km 2008)

website: http://www.shell.com/home/content/ecomarathon/about/current_records/

Marc,

Santa Fe, NM, USA