Blacklight Power in the news again

tombo · Post by **tombo** » Fri Jul 18, 2008 10:12 pm

Some of you may remember the Shell gasoline commercials where they had a "car" specially built for high mileage.
IIRC they were running about 250 mpg.
Of course you could not really use that on the street.
But, it is an example. (If you can believe the source.)
Of course it would be slightly harder to do with a 5000lb SUV.

Of course Carnot efficiency is the limit.
And each fuel has a maximum temperature and specific energy that it can generate, but there are a lot of lines to fill in between that and the mpg.
I'm sure the ASME & SAE boys are all over it.

This has drifted far off topic.
But hey it's the news forum.

MSimon · Post by **MSimon** » Sat Jul 19, 2008 7:04 am

To get that high mileage they ran the engine until the car got up to speed (about 30 mph) and then coasted down and then started the engine again. They were on a track so no brakes were required. Also it was a one person vehicle with bicycle tires. Not a comfortable ride.

So yeah. If you don't mind an average speed of around 15 mph and don't mind going in circles with no traffic 250 mpg is possible. The real world is a little different.

StevePoling · Post by **StevePoling** » Sun Jul 20, 2008 3:52 pm

I have a scooter and thought it got good mileage until I talked to my cousin whose moped once got 225mpg. I was impressed asking how he did it. (He's retired.) He said he never exceeded 22 miles per hour and pushed in the clutch and coasted downhill. I realized then and there that although I would have a lot of fun getting 80-90mph on my scooter, getting more than that would quickly grow annoying.

Meanwhile my boss got a Mercedes diesel SUV. This high mileage game is fun, but any benefit derived by many high mileage vehicles is quickly soaked up by a few low mileage vehicles. I don't begrudge the SUV drivers, because they prove the limits of conservation.