Running on Air: New Hybrid Does Without a Battery

By Rachel Cernansky | February 15, 2009 12:08 pm

hybrid.jpgReducing the cost of the most expensive component of any high-priced product seems the obvious way to increase its consumer demand. Swiss researchers led by engineer Lino Guzzella are working to do just that for the gasoline-electric hybrid car by replacing the battery with, of all things, compressed air. The new car, known as a pneumatic hybrid, replaces a two-liter gasoline engine with one that stores energy in compressed air, which is expected to yield a fuel savings of about 32 percent.

While a conventional gas engine has enough power to accelerate quickly, it more often runs with much less power, like when it’s moving at a steady speed. Guzella’s engine, however, strays from that design. The small engine is sufficient for the car to cruise at highway speeds, but when extra power is needed it relies on a process known as supercharging: because the compressed air is dense, it supplies the oxygen needed to burn more fuel for a boost of acceleration.

The engine also gains efficiency by capturing energy during braking, and saving energy it when the car is stopped: The compressed air can be used to restart the engine, so the car actually shut downs rather than idles the engine when not in motion.

According to Guzzella, the design will add about 20 percent to the cost of a conventional engine, compared with up to 200 percent that current electric-hybrid models can tack on. “Any time you can make the same equipment do more, says one energy researcher, ‘that’s a good thing.'”

Related Content:
80beats: Toyota Sings: Plug It in, Plug It in
Better Planet: Let’s Not Forget Cars While We Freak Out About Everything Else

Image: Flickr / Ian Muttoo

MORE ABOUT: energy, hybrid cars
  • Tim M.

    :…by replacing the battery with, of all things, compressed air. The new car, known as a pneumatic hybrid, replaces a two-liter gasoline engine with a that…”

    The context of the rest of the article makes it clear that the battery is being replaced. Those two sentences, however, are not clear at all.

  • Uncle Al

    Have you ever run a shop air compressor? It’s not a toy and it requires maintenance. If a gasoline tank ruptures, it’s a hazard. If a battery pack ruptures, it’s a hazard. If a compressed air cylinder ruptures it makes the news,

  • Sarah

    All of this is well and good, but what happens when a company like ExxonMobile buys the patent and crushes it… “Who Killed the Electric Car?” is still fresh in my mind. ::sigh::

  • Billigflug

    Hello and good day,

    i really hope that the “Hybrid” project will be more successful in the next years. At the moment we still have to many oil magnates, who follow the aim to earn as much money as possible!
    Hybrid delivers a nonpolluting alternative to the organic load!

    I hope that this fact will get more attention in the next years!

    Thank you very much and have a nice day

  • Jean-Marc Blanchette

    It’ is very interesting to note pneumatic hybrid engines suddenly surfacing in tech media, yet Guy Nègre has been advocating pneumatic engines for over a decade…

    Might I suggest a few points of interest?

    We are coming to an age when Peak Oil is already past us (2005) and the squeeze on fossil fuels is just coming online. New Zealand and Australia are in a precarious position because they are some of the first areas to be directly affected by this prospect, and that is why there is such a focus in that area of the world to develop the aircar, a transitional engine technology primarily based on pneumatics…

    I believe we will be seeing much more in the field of pneumatic technology in the very near future.

  • ATC

    At a “compressed air” station,not everyone will be able to fill their own tank. Air tight fittings to with stand possibly 10 thousand psi, plus the heat/cooling that is generated from compressing the air, will run in the hundreds of degrees F, especially if you want to fill the tank in the same time as you would a gas tank. The valve at the car will at first freeze, then heat. However if they got passed that, some pneumatic only vehicles can get upwards of 100 plus miles before filling the tank… just don’t break it.

  • J L Phelan

    If I read this correctly, the Guzzela approach will still have a gas engine, just one which is smaller than the typical gas-electric 2 liter. I’m guessing it will compress the air so an external compressed air charge will not be necessary. While stored compressed air could start the engine, if the compressed air tank becomes fully discharged, you would still need some battery or other source to start the engine. Maybe we could go back to the old hand crank in that circumstance.

  • Engineman09

    I have Invented a very simple, light weight, extremely frugal and efficient, variable compression, Tri-Brid, Engine with direct energy recovery.
    It is directly compatible with braking energy capture for automotive use without any additional engine parts (other than the control system)

    It can be easily retrofitted to existing Gas Guzzlers as well as to new vehicles.
    Fitting ultra efficient engines to new vehicles ONLY stops things getting worse.
    In addition to OEM the cost effective upgrading of our existing stock of vehicles help REDUCE the current unsustainable levels of green house gas emissions.

    Most people think if it sounds too good to be true then it is (I’m sure you’ve seen and heard many similar claims that have been a waste of time). Well, not this time, I’m not a crank just an ordinary engineer with an idea too big for me to handle on my own.
    twitter @engineman09


Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!


Quirky, funny, and surprising science news from the edge of the known universe.

See More

Collapse bottom bar