A city car can be driven with compressed air for a distance of about 100 miles. Compressed air can be supplied by stations using electricty from nuclear power plants. The problem is that compressing air generates heat that needs to be used to heat homes, industry or green houses to be usefull rather than waste.

As the car drives it exhausts cold air.

there is very small a mag lev train here - i think its at manchester for the airport or something

Wow, compressed air instead of a battery to store the energy to move a small car. I assume the pressure cylinders are a part of the car's structure then. Could be a sturdy little car that would stand up to one of those klutzy SUVs.

Actually I found this on google, might be interesting for our Indian friends:
http://www.theaircar.com/tata_agreement.html

hydrogen cells are also a scam as most hydrogen for them is created by electrolysis (using vast amounts of electricty) or by reacting natural gas, releasing co2 and soot

Mass transit doesn't work, unless a lot of people want to make the same trips. In a city like mine, there are so many different possible trips that mass transit to cover even a tenth of them is prohibitively expensive.

There still is no concrete proof that global warming as a large scale effect is in fact happening, and even less that human actions are causing it. What we have are the opinions of "concerned" scientists with axes to grind.

We do have proof that Mars has global warming.

While we do have better light sources, that is not a justification for Congress banning the old ones. There are special uses without substitutes.

Too much of the whole issue is scare tactics, not science.

The best solution for the CO2 problem is to let the rainforests regrow.

I'm alwyas amused by Americans who say X/Y doesn't work. If you're going to say that, say it doesn't work in America. Because mass transit does work in other countries

About mass transit: the point of mass transit is not to taxi you from point A to point B; rather it's to find a series of points A', B', etc... such that people will be able to make up the difference with their intended route easily. If people weren't scared to walk a little, mass transit can be a very effective system.

On the other hand, there are situations in which mass transit is simply not feasible. In larger cities, (e.g. London, LA, NYC, etc), it works quite well, but I would attribute this to the density of desired destinations (on both ends of the trip). However, in smaller places, like where I live, it's not as effective. We do have public busing, and it does cover a good bit of ground, but it isn't sufficient to replace a car for most families. And then if you were to go out to a rural area, public transit would be either a joke, or a typical government waste of funds.

That's why gov't policies attempt to force higher population densities to create the "demand" for their billion dollar boondoggles.

That is sort of what I was saying. In the US, only the 15 largest cities are really well distributed enough for mass transit to support itself. It works very well in Chicago (I have used it). You can get almost anywhere in two hours or less. New York City isn't so well sited, because of the bottlenecks at the bridges.

In smaller places, mass transit is provided at government expense, solely for people who don't drive. It takes forever to get to any one destination, because the bus takes a circuitous route to reach all of the nursing homes, retirement villages, and dormitories.

I have seen only one smaller town where it might work. The town runs along a river valley. It is long, but only three blocks wide (with two streets running the full length end to end). A steep cliff and the river prevent further development from making the town wider.

In rural settings, forget it.

In my city, I could not ride the transit to work, because the first bus from my home gets to my work an hour after starting time. The last bus that leaves the area of my work passes before I get off work. And one day a week, I have to go to a location 22 miles away.

How far you can walk to the transit depends on your age and abilities, and how much you have to carry.

The demands for swiftness in business also prevent the use of mass transit. The boss wants it done before the bus can get there.

My point was that mass transit is not the panacea that most environmentalists citing only fuel-consumption figures see it as.

My favorite joke on mass transit:

"It is called "mass transit" because the vehicle is heavy. Because of this, it takes a great deal of time to get up to speed. That's why it is always late."

In freezing temps, walking a half a mile sucks. Throw in a little wind and it really sucks.