In the race to develop an alternative to petroleum, no stone is going unturned. Some researchers and automakers are even looking into cars powered by compressed air. But a new development could make cars powered by liquid nitrogen feasible, powerful, and cheap to build and fuel. Sounds cool…heh.

The idea of using liquid nitrogen stems from the use of compressed air to power engines. While most current air cars are light, slow, and not very practical, if you compressed and chill air the main component, nitrogen, becomes a liquid. Liquid nitrogen is also an industrial byproduct, and can be purchased for just 10% the cost of a gallon of milk. Cheap, cheap, cheap!

What has been holding back nitrogen engines is the use of a heat-exchanger used to vaporize the liquid nitrogen. Upon exposure to temperatures higher than -190ºC, liquid nitrogen expands rapidly. A new system injects methanol and water into the chamber as the liquid nitrogen is drawn in, causing it to expand 700-fold, pushing the piston down and creating energy.

Since the liquid nitrogen is already so cold, no cooling system for the engine is required either (though the nitrogen storage tank must be kept quite cold). This could allow for nitrogen engines to be made from cheap, durable plastics, drastically reducing the cost of engine construction.

This idea is nearly as radical as pulling petrol from air or bringing back steam engines. Yet there seems to be a lot to recommend nitrogen as a replacement for petrol. The only area of concern for me is keeping the nitrogen pressurized and cool; a potential tank puncture sounds like a messy ordeal. What are your thoughts on using nitrogen as a replacement for gasoline?

Source: The Economist