A group of final year Mechanical Engineering students of P.A. Aziz College of Engineering and Technology, Thiruvananthapuram, has developed a Compressed Air Rotary Engine that runs on air.

The engine, which uses Compressed Air Rotary System (CARS), is fuel-free. That is, it does not guzzle petrol or diesel and runs instead on compressed air.

The four-member team — Tushar P. Kumar, Al Ameen, Joel Varghese Kalarickal and Nirmal Geo Stephen — pooled around Rs.25,000 for fabricating the engine. The team was guided in the work by Assistant Professor Sreejith B.J.

The engine, made of aluminium, weighs less than 13 kg. The 80cc engine delivers a top speed of 60km/hr. “The idea is to do away with fuel and let nature breathe easy,” said Tushar.

In the first step, a tank is filled with air which gets compressed up to 30 bar pressure. The air is guided to six chambers where the air expands. The potential energy of compressed air is converted into kinetic energy.

This engine does not have pistons like other air engines. Instead, a single ring is connected to a rotating shaft, which turns the shaft clockwise. Since air is not ignited inside the working frame, fresh air is released back into the atmosphere. The speed can be controlled by varying the amount of air let into the engine.

“We got to exhibit the engine at the Bangalore International Auto Expo 2010 held in March.