Can Liquid Nitrogen Replace Gasoline?


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 -190ÂșC, 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

About the Author

A writer and gearhead who loves all things automotive, from hybrids to HEMIs, can be found wrenching or writing- or else, he’s running, because he’s one of those crazy people who gets enjoyment from running insane distances.

  • It’s all about EROEI, it always is, I bet it’s very low and poor….


    • Bukkiah


    • If you use solar or wind to produce LN2, then your EROEI is exponentially greater than any petrol-driven fuel. Keep in mind that the “raw stock” for production of LN2 is air; since air is in unlimited supply and isn’t controlled by any petroleum company, you are free to produce as much LN2 as you can produce/use/distribute without having to mine it/drill for it/dig for it.

  • Bukkiah

    Not sure how liquid nitrogen is a byproduct of industrial processes. It still has to be refrigerated, otherwise you could just chill air. So the cost, just like compressed air is in the condensing to fuel density. Compressed air by exothermic physical compression (typically) and a very lossy heat wasting enterprise, therefore clean IF the source of energy to compress is clean.

    Nitrogen (in its liquid form), as far as I can tell still costs money. So is chilling a better way of compressing? I think you waste too much energy here making it a wasted enterprise.

    I don’t understand how its envisioned that you can have plastic engines. It still has to be strong enough to withstand the expansion. Also plastic can crack if too cold. Hard to get a material that can withstand the temperature difference.

    • Bukkiah:
      Liquid Nitrogen (“LN2”) is easily manufactured. You can find LN2 production units in dermatologist’s offices and orthodontist’s offices – and many universities make several thousand liters per day using only solar or wind power.

      You are correct when you say that it costs money – I don’t believe any fuel would be “free” to manufacture. As a matter of fact, LN2 prices have risen by 50% in the last 30 years – from $0.06 per liter all the way up to $0.09 per liter. Gasoline and diesel, on the other hand, has risen more than 400% in that same time period…and as you’ve probably noticed, both gasoline and diesel continue to go up. LN2 prices have remained at $0.09 per liter for the last 10 years. One reason that prices have skyrocketed for petroleum-based products is the fact that the raw material used to make gasoline or diesel is dwindling in supply, and becoming more expensive to find, transport and refine in order to turn it into fuel. LN2, on the other hand, uses raw material that is in plentiful supply – air. Since air is almost 80% nitrogen (and no one controls the air we breathe), making LN2 is quite simply a matter of cooling air. Since LN2 can be made using solar or wind power, and is derived from air, it is truly 100% renewable and 100% carbon neutral.

      Finally, our company does make a “platic” engine. We manufacture a carbon-fiber/Kevlar turbine that uses liquid nitrogen. We store the liquid nitrogen in carbon-filament tanks that have outstanding insulation qualities. Since we keep the LN2 at ambient pressures, we provide vents that don’t allow the tanks to exceed a minimal amount of pressure. Our oldest filament-wound LN2 tank is 5 years old, and we have absolutely no cracking, splitting or other fatigue (because we don’t pressurize them in any way.

      • And how far would a liter of LN2 get you? and how much space does it take to store a liter of LN2 in your fancy tank compared to a liter of petrol in a standard fuel tank? And how much more would your carbon fiber (which isn’t plastic) engine cost than a steel or steel / aluminum engine?

        And regarding the original article, while you wouldn’t need cooling, you would need heating. once you absorb all the heat energy from the system the LN2 would no longer expand as much reducing the kinetic energy output.

  • I’m not sure if I’m understanding “…how far will it get you…”, but I’ll give it a shot. Using our technology, it takes about 3 liters of LN2 to do the work that 1 liter of petrol does. So, if a liter of LN2 costs $0.09 (American), a liter of petrol costs about $1.36 (American). Simply put: you do the same amount of work for $0.27 using LN2 that it takes you to do $1.36 cents using petrol.

    There’s no magic to an insulated tank that carries liquid nitrogen. It takes the same amount of room (capacity) to store 1 liter of petrol as it does 1 liter of LN2 (or 1 liter of water, for that matter). Using “hybrid” technologies, our system does not require any more space to store fuel than does a petrol. We can turn out a 70 liter tank for the same money that it takes to produce a 70L tank out of plastic (the kind used on most vehicles today). As far as cost to produce engines: our turbines cost approximately one-fifth to produce, in quantity, as does a petrol-burning motor made of steel, iron or aluminum.

    We do require heating, but unfortunately I can’t explain to you how we accomplish this (because it’s proprietary and part of our patent). I can tell you that we have thousands of hours of operating time using our turbine to prove that the concept not only works, but works well in all environments. You can see the products that we currently produce at There you will also find more information (under “FAQ”) on how the system works.

  • Thank you. I was happy to find out about your work on your website. I am webmaster of talking about cars running on compressed air and would very much appreciate to be kept posted on what you do. I will follow you on Facebook. I am particularly looking forward to your applications in vehicles. I wish you all succes!

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