by Wildwell » Sun 14 May 2006, 17:51:36
$this->bbcode_second_pass_quote('gg3', 'T')here's a world of difference between a rational critique and an emotional tirade. The intensity of the scorn & contempt shown by some of y'all tells me it's not about the car, it's about your head: a psychological defense mechanism to ward off unwelcome facts in order to preserve a specific emotional outlook. Fine, go right ahead, and good luck.
Strictly speaking, an 8,000 mpg car is a demonstration project only, i.e. sure it's not practical for daily transport. However, that doesn't mean that some of the design concepts can't be used in practical vehicles of one kind or another. Even if only in single-seater velomobiles, which after all are quite popular in Europe.
As for achievable efficiencies, I'm shocked that no one here has mentioned the 312-mpg VW prototype that was first shown a few years ago. It's a 2-seater, looks like a cross between an oldschool Messerschmitt and a futuristic Porsche speedster, and does Autobahn speeds with ease. A production version of this thing could probably be built and get over 200 mpg easily.
Now if VW can get 312-mpg on a viable car for highway driving, a velomobile with some of that British technology might reasonably get 400 - 500 mpg.
As for "SUV roadkill," I have a solution for that: Active Deterrence. Sensors in the micro-vehicle would detect if it was compressed in any dimension sufficiently that there would be no way the occupants would survive (for example if it were run over and squished). In that event, a large explosive charge would be set off, thereby destroying the attacking SUV and killing all of its occupants as well. Neat, huh?:-)
The trouble is single seater or twin seater car in Europe in not that popular. They have been incredible sales failure. Round this part of the world, even with $9 a gallon fuel, the SUV is becoming more and more popular, especially for the lady driver taking the children to school. The reason cited for these large cars are: Status, safety and all weather use. This is why the *average* fuel consumption figures have hardly improved. When people look to buy cars they look for space, the ability to trawl the family and their things about as much as anything else.
The point is, this ‘car’ isn’t anything especially clever because it isn’t a car in the normal sense. Very often these show vehicles are produced for trials and driven by 14 year olds at pedestrian speeds on flat race track. There’s nothing clever about it, nor is it real world conditions, because the laws of physics get in the way every time. You need a certain amount of power to propel a certain weight/size of vehicle along. Obviously other factors come into play like the drag coefficient, rolling resistance, potential energy, economies of scale, weight and so on. You can store energy through flywheels or hybrid batteries.
A lot of these quotes for so-called high MPG cars are dishonest - they might rely on an input of energy such as electricity, and not take conversion losses into account. Or, they may get high MPG in much specialised conditions.
In this case the inventor says ‘"I think the car is important because it is a reminder to us all that the way to achieve fuel-savings is to drive lighter cars - it's the weight of this car that is the main reason for its fuel-efficiency,". Well great, but is it a go-kart and not practical to take the family out and load shopping into it in heavy rain.
It’s worth noting the only commercial micro car sold in any sort of numbers, the Sinclair C5 was also a spectacular failure, mainly for practically reasons. Trouble is some people are giving the impression folk can have their cake and eat it.
One thing that's very important to recognise which will prevent a high uptake of this sort of vehicle is crash worthiness. Cars (and buses and trains for that matter) are getting heavier because people demand vehicles that can survive collisions, the regulations are enforced by law. While new materials might be able to be used, it might be at a considerably higher cost.
http://en.wikipedia.org/wiki/Sinclair_C5