Various companies are investing in the research, development and deployment of Compressed air cars.
Overoptimistic reports of impending production date back to at least
May 1999. For instance, the MDI Air Car made its public debut in South Africa in 2002, and was predicted to be in production "within six months" in January 2004.
As of January 2009, the air car never went into production in South
Africa. Most of the cars under development also rely on using similar
technology to low-energy vehicles in order to increase the range and
performance of their cars.[clarification needed]
MDI has proposed a range of vehicles made up of AIRPod, OneFlowAir, CityFlowAir, MiniFlowAir and MultiFlowAir.
One of the main innovations of this company is its implementation of
its "active chamber", which is a compartment which heats the air
(through the use of a fuel) in order to double the energy output. This 'innovation' was first used in torpedoes in 1904.
As of January 2009 Tata Motors of India had planned to launch a car with an MDI compressed air engine in 2011.
In December 2009 Tata's vice president of engineering systems confirmed
that the limited range and low engine temperatures were causing
Tata Motors announced in May 2012
that they have assessed the design passing phase 1, the "proof of the
technical concept" towards full production for the Indian market. Tata
has moved onto phase 2, "completing detailed development of the
compressed air engine into specific vehicle and stationary
In February 2017 Dr. Tim Leverton, president and head at Advanced and
Product Engineering at Tata revealed was at a point of "starting
industrialisation" with the first vehicles to be available by 2020. Other reports indicate Tata is also looking at reviving plans for a compressed air version of the Tata Nano, which had previously been under consideration as part of their collaboration with MDI.
is an Australian company which has produced prototypes of a variety of
prototype small vehicles using an innovative rotary air engine designed
by Angelo Di Pietro. The company is seeking commercial partners to utilise its engine.
and Citroën have announced that they too are building a car that uses
compressed air as an energy source. However, the car they are designing
uses a hybrid system which also uses a gasoline engine (which is used
for propelling the car over 70 km/h, or when the compressed air tank has
On January 2015, there was "Disappointing news from France: PSA Peugeot
Citroen has put an indefinite hold on the development of its
promising-sounding Hybrid Air powertrain, apparently because the company
has been unable to find a development partner willing to split the huge
costs of engineering the system." Development costs are estimated to
500 million Euro for the system, which would apparently have need to be
fitted to around 500,000 cars a year to make sense. 
The four laws of thermodynamics are: