Thursday, December 11, 2008

MDI Dual-Energy - 4 Modes of Operation?

Just hold on a minute there... the MDI dual-energy engines have HOW many modes of operation exactly?

What do you mean, FOUR... ?


Four operating modes: 

  • Mode 1, mono energy compressed air: below 50km/h, only the compressed air in the tank is used.
  • Mode 2, simple dual energy: range extension by using the compressed air in the tank which is heated using an energetic adjuvant for the external combustion chamber before it is introduced in the engine.
  • Mode 3, autonomous dual energy: beyond 50 km/h the stored compressed air in the tanks is not used anymore.  •A combined air compressor produces compressed air at working pressure which is then heated in the external combustion chamber before being transferred in the active chamber and expanded in the work cylinder. 

This operating mode is also used below 50 km/h when the tank is empty.

  • Mode 4, Dual energy with recompression of the tanks: an energy sharing occur using part of the produced compressed air (by the combined compressor) to run the vehicle (as in mode 3) and rest is directed towards a booster to refill the tanks.

So, when MDI says DUAL-energy modes, they don't mean "dual" as-in "two"...

The more I learn about this, the more impressed I become with the whole concept... it's simply AMAZING!

The thing I'm not too certain about is why I never noticed this explanation on the website before? Was it even there the last time I checked? 

I'm really not sure... How puzzling.


  1. Has this dual mode actually been built and tested?

    MDI has a history of grand announcements that never get built and definitely never make it to the market. is the only tests MDI has published as far as I know. That test showed the car running out of compressed air after less than 5 miles.

    Where are the cars that in 2000 MDI announced would be on sale in South Africa in 2002. and ??

    Or the ones that were to go into production in 2004/2005:

  2. An anonymous comment... how valid can this really be? interesting...

  3. Well, mister anonymous, I have watched your links and you are completely right: MDI has announced several times in the past the launch of an air car and every time it has been postponed. What does this mean? The reason why they did this is that MDI is a small family business that was in need of cash to develop further its technology and that at various times it had signed a contract with investors (Italy, Britain). Therefore they were confident that a breakthrough was eminent and they made this public. Then after that it turned out that these investors didn't pay what they had promised. So no money and the promises couldn't be lived up to. Developing a new technology means paying your engineers, and for several years MDI was going through a very black spot, not able to pay for its people. But then, early 2007 Tata Motors (India) payed 20 million euros for a license for India, after having examined thoroughly the concept for 30 months. Tata is the 5th biggest car manufacturer in the world. They wouldn't have done so if MDI's technology was not valid. Now KLM and AirFrance have decided to test the MDI aircars on the airport tarmac and wish to buy a fleet. Also the city of Nice (France) has ordered a number of cars. Are they all stupid?

    All I retain of you post, is that it takes much more time than was first thought. But the the rich Mercedes had to postpone the launch of the after all not so revolutionary SMART by 3 years. So please be patient, keep an open mind on it, and we'll watch this exciting new year 2009 with you and see if this new technology will be able to deliver as promised. We have nothing to loose here, and MUCH TO GAIN!
    Thank you,

  4. Thanks Didier.

    Just a note, I talked with Shiva Vencat about e.volution in South Africa and they are a legit zone licensee for MDI. They got a bit ahead of themselves in a BBC interview and now people use that as an excuse to bad-mouth MDI.

    Remember, if you don't see it on, take the any information with a grain of salt... even if it's good news.

    The latest fakery was 2008 blog/articles saying Tata Motors will create 6000 air cars for "next" summer (2009). I tracked down the author and he realized that he was quoting a 2007 blog and not quoting Tata or MDI.

    Talk to you again soon.

    Paul Ryan

  5. Catvolution, did Shiva Vencat happen to mention that he is a co-founder (with Helen Brown) of ZPM SA (Pty) Ltd.?

    Starting retail sales in 2003 wasn't just a single overenthusiastic comment to a BBC reporter. The ZPM website also said the same, along with regular updates of what was happening in France. For example, the news in June 2001 was "Availability of the first vehicles in South Africa is still on stream for 2003. The commencement of the construction of the Gauteng production facility is planned to coincide with the successful SABS commercial homologation of the pre-series vehicles arriving from France in November 2001..........Pre-series vehicles are currently in production at the Nice plant in France. These are being built to EC regulatory standards and form the basis of stock to be sent to each participating region (eg. Mexico, Australia, Italy, Spain and more) at the end of the year <2001>. Each region uses these vehicles for regional homologation and project start-up. The second and model plant is already under construction adjacent to the first production facility and is due for completion in October 2001."
    These statements are consistent with what you will find on archived pages. First it was homologation at the end of 2001/early 2002, then at the end of 2002/early 2003, then towards the end of he year 2004/early2005. Similarly, did indeed say that pre-series vehicles were to be built in France in Dec 2001. Then Dec 2002. Then ????

    To recap. These statements about specific schedules in October and November 2001, were made in June 2001 on the website of the MDI franchisee, whom one of the co-founders was Shiva Vencat.
    You can easily verify the statements about Shiva Vencat being a founder and the schedule by going to and plugging in .
    Click the "Business" button on the left to see that Shiva Vencat is one of two founders (Of course, this might be a different Shiva Vencat than the current CEO of ZPM in the US, but the website does identify him as being in New York.). Click the What's New button on the top to see the updates on the status of moving towards production and sales.
    The next time you speak with Shiva Vencat you might make some further inquiries, but it does appear to be more than simply "They got a bit ahead of themselves in a BBC interview"
    As a founder and most likely a major shareholder and officer of Zero Pollution Motors South Africa (Pty) Ltd, I would be surprised if Shiva Vencat doesn't have additional info on what happened to the effort, which appears to have been completely abandoned.


  6. Catvolution: "They got a bit ahead of themselves in a BBC interview and now people use that as an excuse to bad-mouth MDI."

    It is "bad-mouthing" to point out a history of not ever delivering, in spite of multiple promises to do so?

    Is it not worthwhile trying to figure out why all of these projects failed?

    I don't think it was a conspiracy by "big oil", but rather simply that the cars did not have adequate performance, and I have not seen anything to indicate any improvement in the performance when powered by air.

    Adding the ability to run on fossil fuels may very well be what is needed to make the performance acceptable, but now then they are simply competing with other efficient fossil fueled cars.

  7. In 2008 I posted "Has this dual mode actually been built and tested?

    MDI has a history of grand announcements that never get built and definitely never make it to the market."

    It appears that the dual mode still has not been built and tested.

    MDI has announced multiple times that the Airpod will go into production, but that has not yet happened.

    Do you have any insight into why MDI continues to do this?

  8. July 2011 update: Zero Pollution Motors, the USA distributor/licensee with Shiva Vencat as president appears to have shut down. Their website is dead.

    Catecar, the Swiss distributor planned to build a factory and start production in March 2011. That didn't happen and Catecar intends to sue MDI for failure to deliver technology as promised.

    MDI was also supposed to go into production many times over the last two years, but this has never happened.

    MDI has abandoned the original Airpod engine and is going back to the 3 stage design of 1998 to 2004 timeframe.

    The MDI website has not been updated since November 2010, and there is no schedule for production start.

    As usual, nothing happens.


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