Why hasn't automobile mpg technology progressed like other technologies?

Question

The Model A got 25mpg. Current cars get 'maybe' 40mpg. It's been 100 years. Cell phones have gone from 5 lbs and the size of a brick, to mere ounces and fit in the palm of your hand. Computers have gone from filling a building, to the size of a book. Airflight has gone from a few feet, to around the world at super sonic speed, and to outerspace. So---- in the face of all these facts, WHY has the mpg for automobiles NOT EVEN doubled in 100 years??? Given all the advances in ALL other fields, medicine, communication, science, even other forms of transportation (boats, ships, planes, spaceflight), we should have cars that are getting 300mpg or better!! WHY DON'T WE?!?!?!?!

Answer 1

if i understand correctly most of the science that has gone into getting more out of gas has gone into getting more horsepower instead of more mpg.

Answer 2

Because there is a fixed amount of energy in a gallon of gasoline. The main reason that diesel engines get better mileage is because there are more BTUs of latent energy in a gallon of diesel than a gallon of gasoline.

The fuel economy that you can expect is directly related to the efficiency of the conversion of the latent energy in the fuel to kinetic energy by the engine.

A typical family sedan that gets 25 MPG today might have a thermal efficiency of 30% at best. Even if you were able to increase that to 100% you'd only improve fuel economy to about 80 MPG. That's the theoritical limit; you can't do any better than that.

With friction and heat losses in even the best internal combustion engines we'll never likely see anything much better than 50% thermal efficiency.

The earliest engines, external combustion steam engines, only had a thermal efficiency of 2 or 3 percent. The gasoline internal combustion engine was a quanturm leap in thermal efficiency -- up into the 15% - 20% region even in the earliest engines.

Improving upon that initial level of efficiency has proven to be an extremely difficult task. Increasing compression does increase thermal efficiency -- the other reason that diesels get better mileage -- but there are practical limits as to how high you can go. The addition of turbo chargers improves thermal efficiency by capturing some of the energy lost out the tailpipe as wasted heat. But again, there are limits.

The only other way to increase fuel economy is to reduce the mass of vehicles overall. That's been done in Europe and Japan for many years. What passes as a "full size" car in Europe is half the size of what Americans call "full size" as anyone who's ever been to Europe knows full well. The main motivator there was fuel costs -- taxes are very high in Europe. A secondary consideration was space, plain and simple -- smaller vehicles take up less space on roads, need smaller garages, etc., an important factor in high population density areas.

We COULD make a fully functional car the size of a pop-up toaster that would get 300 MPG or better. But nobody could drive it!

Answer 3

There is no incentive for automakers to increase fuel standards. Investing in new technology will only hurt their profits. Only Congress could move things forward and the auto companies and oil companies pay millions to lobbyists each year to make sure that never happens. Congress might change their tune if people were up-in-arms about it but like most things the public are rather apathetic about it.

Answer 4

why dont we? mostly because legislation doesnt require them to.

however,....

the model A weighed 1250lbs, didnt pass any kind of emissions requirement, and probably was not an ergonomic environment. no air conditioning, no heater, safety considerations, no stereo, and probably needed a whole lot more maintenance than a new ford with a 100000 mile warranty, etc.

todays cars a bigger, faster, safer, more comfortable, more reliable, more emissions friendly, more easily recycled, more ergonomic, more everything except simple than cars of yore.

you want a high milage vehicle, get a scooter like vespa.

Answer 5

invoice Gates is definitely an agnostic and locate faith has reward. he's only unsure if there is or there is not any longer a God. assorted scientists are Christians or belong to a faith. that's a mix. As on your photograph voltaic gadget real sources, i could have faith that God is delighted that somebody is looking after the planet. i'm too.

Answer 6

Big oil buys all the good ideas then sits on them.

Answer 7

buy a50 cc scoter 100mpg deal with it

Answer 8

the oil companies!!!!!!