Again a compressed air technology from France. I wonder whether Guy Nègre had any involvement with this project from PSA. Last time I heard he was talking to TATA.
Anycase this sounds like a very good concept, doing away with those expensive batteries. Sounds a lot more environmental friendly than those chemical concoctions.
Europe and Asia seems to be the only players capable of bringing fuel economy to the masses. The States are still too busy denying that energy is becoming a scarce resource.
Mel Tisdale
Why not simply use the gasoline engine to drive the compressor which in turn powers the air motors which then drive the wheels without any other drive-train components? The compressed air storage would then simply be a 'capacitor' that kicks in to meet high demand while accelerating, or for emergency propulsion to get the vehicle to a place of safety in the event of an engine failure.
Having a motor driving each wheel could make wheelspin as near to impossible as makes no difference and 4 X4 models simple to produce.
Jesse Blenn
PLEASE don't be misled by their name for the system - this a hybrid HYDRAULIC system! That is air (or a more inert gas) is just used to maintain pressure in the accumulator, but the working fluid is hydraulic, that is why they have the hydraulic pump and motor. That makes good sense and is a self-lubricating low-maintenance system. Air as a working fluid is pretty stupid because you need huge reservoirs and lose energy as heat every time air is compressed and must regain it every time the air is used - hard to do in cold climates. And forget the fairy tale about filling it at the gas station tire hose! I have been advocating such hybrid hydraulic systems for years, but in my case I would use a pure hydraulic drive also with hydraulic wheel motors. However I am inclined toward electric to get away from petrodollars.
I have always wondered why they just didn't use hydraulics? Motors generate incredible torque. Could be placed at each wheel. Very good at recapture of energy during braking. Small pressure reservoir. And by the same token, dump the heavy and expensive batteries. Most energy lost during re-accelaration so use the stored braking energy then. Cruising at highway speed requires about a dozen horsepower in today's smaller aerodynamic efficient cars. Use a highly efficient small motor for the extended range highway mode and to aid the acceleration process. You can't expect 0-60 in 6 seconds and 60 mpg.
Not a compressed air hybrid, this is a hydraulic hybrid using accumulators. For a true pneumatic hybrid look up the scuderi cycle engine.
Pity they reverted to the hydraulics and the associated component weight and cost. The comment by Jesse makes no sense as the energy storage in this hydraulic system is only provided by the air volume in the accumulator. However, by using an oil working fluid a second low-pressure tank of equal volume is needed. With pure air, there is no need for a low-pressure container.
The heat issues associated with the much simpler use of air alone can be neatly met in by tapping the intake or exhaust of the ICE.
Jim Sadler
About the only good use of compressed air would be that first turn or two of a wheel from a dead stop. Even then it is an very shaky idea. More parts, more friction, more lost energy, more weight, more expense all point to a bad idea. For city cars I could believe a one cylinder diesel powering a good alternator into a battery bank. Batteries are progressing. I suspect the only reason we are not seeing faster changes in battery technology are companies trying to recapture investments in technologies that were surpassed rather quickly. It is rather like personal computers. Once you invest in a design you need time to make a few bucks before you set lose the next monster computer.
at 116 mpg, i'm impressed...
Gavin Roe
they had a very similar system fitted to buses in Adelaide 20 years ago they used the stored air from braking to accelerate the bus from stationary.
The great thing is that every day we (collectively not just Europe and Asia) are making great technological strides in many areas including Solar, GeoThermal, and Nuclear so I love to see these new innovations like this compressed air technology. I hope it works though I see some serious limitations in using compressed air.
Heck, we could all jump forward in mileage if we used nothing more than a system that would get the vehicles from dead stop against all that inertia to a moving speed where the ICE can run relatively efficiently.