A compressed air car is a great idea and should have its place in world transportation. My question is; "What energy source do you use to make the compressed air?" Hot air? Nope! Atomic? Unsustainable, potentially dangerous, radioactive waste! Fossil Fuel? Pollutes, not enough of it! Food grade vegetable biofuel? Takes too much needed food off of the table. How about algae biodiesel produced in a closed loop, using sunlight and a little water to produce 33,000 gallons of biodiesel, to produce electric, to produce compressed air while recycling produced carbon back into the production of more algae! You could also eliminate the compressed air step and power everything with pure nonpolluting electricity derived from closed loop, carbon eating algae biodiesel, www,valcent.net.

solarnano, Hua Hin, Prachubkirikhan

Sound like a "Load of Compressed Air" to me.

Lionel, Gloucester,

This project was presented by MDI already at the Bologna's Motor Show, Italy, in 2001.
I hope it's working out, this time.

Andy, London,

Why couldn't MDI have teamed up with Peugeot or Citroen to produce a car that is visually appealing? No matter the technology, if the vehicle has not got the right asthetics, it will be doomed to failure in the West. Lets take the Prius for example, the technology behind it makes perfect sense although not in the Prius's case because of the energy required to manufacture and dispose of the batteries etc. Anyway I digress, the point is that the Prius still hasn't got the visual appeal to make it the bestseller it could potentially be (minus the technology concerns).

ANDREW EZEA, Hackney, LONDON

I wouldn't want to be in this death trap when it hits a pickup truck or a bus (or a lamp post). Second point: the total cost of energy is greater than direct use of the energy due to all the inefficiencies of the total system (can you say "thermodynamics"?) It's just another bit of smoke and mirrors all pimped up to be "the next great thing".

Chuck in st paul, St Paul, MN

As one poster said, compressing air produces heat, lots of it. Dive operators know all about this and have to keep the tanks being filled in a water bath. Even if the air is compressed in advance, the process of filling a tank is by no means instantaneous. Another point is that using a relatively large bore connecting pipe will give another danger. If a pipe with high pressure air, say 3000 psi, (standard dive tank pressure) is broken the free end will whip violently. At least one operator of my acquaintance had an accident when a flexible pipe with a 1/4" diameter bore broke. The end caused severe bruising and cuts on the arm of the nearby person. The air flow is now controlled by a plug with a 0.040" diameter hole to permit air flow. Of course it takes a bit longer to fill the tank, but at least its safe. Tank weight is the other bugbear, a tank that can propel a car 2/300 kms will be big and HEAVY. 3000 psi means that there is a force of 3000 lbs on every square inch of the surface

Tony Edwards, ROAD TOWN TORTOLA, Virgin Islands

Sally buy a bike!

John Gresham, Waterloo, Merseyside

I'll buy one if they come to the UK. I never drive over 70 mph anyway (usually only 30/40 mph) and never drive more than 6 miles per day at the most. Maybe I'll use the foot pump instead of going to the gym! I just hope this one makes it to the mass market.

Sally, uk,

I hope it won't share the fate of EV1 - the electric car from California (check the film: "Who killed the electric car?".

if you think that you like the environment and that you care - you have to see this film!

George, London, UK

I'm curious to know how big the air tank is and what pressure it's at. How heavy is it? (Mass is expensive to accelerate.) What are the safety implications compared to a tank of petrol?

Norman, Anstruther, UK

Fredric, some 'law of physics' argument or other comes up whenever something like this is reported. Why would anyone with an open mind jump to the conclusion that the air is being compressed at the point of supply rather than the more sensible option of compressing it in advance. Apart from anything else, compressing it to order just couldn't be done in the minutes allowed for. In addition, one can see possibilities for inefficient but free solar systems being used to supplement the mains power for the compressors.

And George, the internal combustion engine is famously inefficient. Power station probably produce less pollution per mile if the power is converted in this way.

Peter Ryder, Middlewich, UK

A wind turbine could compress air directly without the
intermediate step of generating electricity.

John Boyd, Houston, Texas, USA

Brown will love this. He'll actually be able to tax the air we breath.

DickW, Aberdeenshire, Scotland

New petition on the government website calling for real action on climate change.. sign it if you care about the future. We need technology like this car to be widely available and huge amounts of government research to be put in, not relying on a family business in France. The government is just not acting on this as it is in thrall to the big oil companies

http://petitions.pm.gov.uk/Fight4ourfuture/

Ian, Nottingham,

Great 'out of the box' thinking, and as someone's pointed out, they could be refuelled largely from renewable sources.

The key to their success is their low weight at 350kg (my family hatchback weights about 4 times that!). We need auto designers to get on a virtuous cycle of lower weights and speeds, equalling less fuel needed to propel them, and fewer resources needed to build and maintain them.

In the past 30 years we've just exploited more efficient designs and materials, etc. by making cars heavier and heavier, and giving them pointless excess performance!

paul newbold, sheffield, UK

Clarkson will hate it - no throaty V8.
The petrol companies will hate it - no revenue.
Where can I buy one?

GJB, SLOUGH, BERKSHIRE

This isn't a breakthrough, it's the equivalent of blowing up a giant balloon and strapping it to a car and letting it go. This air is compressed using electricity and in India that means coal, the most environmentally unfriendly of all fuels, even among fossil fuels.

George, Grantham, England

I suppose you get the children to compress the air after school in the first place? Free energy? No way!

David Vinter, Louth, Lincs., uk.

My brother in law's dad made one of these nearly 20 years ago.

They work.

The range is, optimistic, I think.

Charles, London,

Let's see what Jeremy Clarkson has to say about it

Mike Laughton, Runcorn, United Kingdom

Why are alternate energy sources not developed? Ask the rapacious oil companies that question. As long as the oil companies have the power they now have, they will be not allow mass scale alternate cheap energy source vehicles to ruin their profits. Oh yes the governments are in collusion with them for the taxes they levy on petroleum products.

Faqi, London, UK

You all need to look up basic physics before getting too enthusiastic. Hint: what happens to air when rapidly compressed? It heats up....

You could compress slowly for eight or ten hours and get high pressure, not waste all the energy on heating up the air, and get a decent range. Or you could compress in a couple of minutes and cut the range by 80%.

Or you could rewrite physics, which might, now one thinks about it, be a lot easier than making a car run on stored compressed air....

Frederic desLauriers, Paris, France

i cannot imagine that a car carrying a tank containing air compressed to the level required to move 1,000 lbs 200-300 kms would be allowed on the street.

compressed air may be a fuel of the future - and it always will be.

liam murphy, stamford, connecticut

Wow!! I hope this catches on. Too many alternative fuels have been promised and just... haven't really happened...

Anna, Plymouth, UK

Of course if you get a footpump, you can always recharge it yourself;)

Once these are in common use, will the governent finally introduce legislation allowing it to tax the air?

Ron, Milton Keynes, Bucks

John, you are absolutely correct and the same applies for hydrogen powered vehicles. However, sice compressed air could be made using renewably generated electricity there is the potential for a zero-carbon supply chain here. In short by moving the release of emmisions from point of use to point of source the you CAN have a zero-emmisions vehicle. Something not possible with hydrocarbons...

Because you could put an air comressor anywhere there is a plug socket it would, in effect, negate the emmisions from the supply and distribution networks intrinsic to hydrocarbon fuels.

Olly, London, UK

Great comment Gary. Thanks!

chetas, croydon, surrey

Will these things fit in the back of a Jeep?

P. Fraser-Brenchley, Aberdeen,

Does a full tank lasting 10 hours mean of use?
if not then the only problem i have is that a full tank lasting 10 hours and a range of 200-300km means a speed of 20-30kph.
Thats 12-18 mph, i don't it would be popular until it can average 30-40 mph even for city driving.

Then again i would love one for the cost.

Damian, Leamington,

This is not a zero emissions car its a zero emissions at point of use car, the pollution will either be generated at the air compressor or at the power station that produces the electricity for the air compressor.

John Gresham, Waterloo, Merseyside

I actually ordered one about 3 months ago. I recieved an e-mail saying that i'm now on the waiting list; They also explained in the e-mail that you can invest in the company-either 5.000 euro or more. The advantage of buying this car as a French resident and (unfortunately) French Taxpayer is that we get a 5.000 Euro tax rebate for the purchase of a low CO2 car. Less than 50 g/l! The French government obviously didn't know about this car and the owner of MDI has been keen to talk about it on a couple of radio shows." basically you're getting a free car that costs the end-user 1.50 Euro for every 100km's. I would imagine they have sproduction problems. I shall be visiting the factory in the Nice area very shortly and get a closer look. They are keen to sell production licenses all around the world. The idea is to produce locally. i'm not sure if that will work; One great big bloody factory in India would do the job! Here's their web-page:
http://www.mdi.lu/fra/affiche_fra.php?page=infrastr

Gary Lawrence, Montpellier, France

I will buy one now

Andrew Gilbey, PAlmerston North, NZ