Fssssssssssst!

Definitely not full of hot air after a little driving. OTOH, air conditioning wouldn't be a problem! Heating and lights might require batteries, though.

At some level this seems similar in approach to the idea a few years ago of using flywheels instead of batteries. The basic idea is the same; you can store a lot of mechanical energy in a small space if you are clever about it. Unfortunately, that technology never seemed to take off despite a lot of hype (see for example http://discovermagazine.com/1996/aug/reinventingthewh842 this article from 1996). However, both flywheels and compressed air share the same essential problem as hydrogen; you still need to get the initial energy from somewhere. Thus these aren't true sources of power like gasoline. Even if this technology works very well, it will still need to take power from the general grid.

I remember seeing an article about this on Slashdot/Wired about a year ago.

Even if it does require an external power source to charge/recompress the air, and a battery for the auxiliaries, it's still going to require comparatively less power than most cars. (IIRC, it also uses vegetable oil for the lubricant.)

It's good to see that it's finally getting some coverage from the MSM and not just tech publications.

Even if this technology works very well, it will still need to take power from the general grid.

When ScienceBlogs did their Next Generation Energy series on alternative energy, I suggested that a combination of using wind generators for the electricity to power the compressors that charge the car is a great way to reduce the need for a carbon-based transportation system. Apparently the folks at Shell, who sponsored the series didn't think too much of the idea.

As we engineers say, things can be split to three parts: the beginning, the middle, and the end. In energy business the beginning is generating the energy, the middle is distributing it, and the end is using it. This car only addresses the end part.

There is one very good system for the middle part: the electricity grid. But it can only forward energy, not store it. Storage with high efficiency would really be a winner. You could generate solar electricity in the summer, and use it in the winter. In that respect chemical methods (i.e. fuels) perform much better. Batteries, capacitors, flywheels, and compressed air have far lower storage densities.

The beginning has its own problems, and they are pretty independent of the other two. Solar panels or windmills don't need this car to be feasible.

Near the equator, the earth's surface is moving in one 'direction' at about one point five mach. Most of the planet is sitting there at several hundred or a couple/few thousand degrees C. The planet is moving through an weak ionic field at almost 70,000 miles per hour. If I had an object in the lab moving at 70,0000 miles an hour (for free ... it just comes that way) through a weak ionic field, I could make energy from it.

Wind power is, of course, exploiting the rotation. We do use a tiny bit of geothermal. But the magnitude of available energy is startling compared to what our tiny earthling minds seem able to tap.

Lassi Hippelainen suggests 3-part consideration: beginning, middle, and end (generation, storage/transport, use) --- a good point. Seems there is a fourth issue, afterlife, which we humans are struggling to incorporate into our thinking. That is, what is left after use? pollution, toxics? an excess of some elements or substances?