Air Car

This is a fun and fascinating idea and I don’t want to appear nit-picky but the headline and body of this story commits an error and promotes a myth that most “alternative” energy stories are guilty of.
There is no “low” or zero pollution hydrocarbon fuel alternative vehicle and all practical implementations (that I know of) except for fuel-electric hybrids in fact pollute more than internal combustion engines burning fuel derived from traditional hydrocarbon extraction.
We are often advised that to really understand politics we should “follow the money”. To understand the above statement all one has to do is “follow the energy” and ask, “How does the energy that powers the vehicle get to the vehicle?” In this case the vehicle’s energy is stored in compressed air. How is the air compressed?
If the energy to compress the air comes from electricity and that electricity does not come from a hydro-electric power plant, or from a nuclear fission power plant, or from a solar, wind or other non-fuel burning source (all of which have their own pollution or environmental impact problems) then it comes from a hydrocarbon burning power plant. For brevity lets call such plants “traditional power plants”. With few exceptions traditional power plants dominate human energy production and other potential major-player alternative sources are either impractical or politically inviable.
The transmission losses of electric power from plant to end user are significant. If we were to be unrealistically optimistic and assume a loss of only 50% (losses are typically much worse) it is easy to see how burning twice as much fuel at the plant does not translate to a net pollution “savings” over burning a similar fuel at the vehicle. While power plant energy production efficiency may be greater than a vehicle’s engine any advantage is more than swamped by transmission losses. Moreover, scrubbing what fuel burning power plants exhaust is no more effective than scrubbing the exhaust at the vehicle itself.
Energy is a lossy matter and many folks simply do not grasp this unavoidable reality. Consider ethanol and follow the energy. If the energy used to make a gallon of ethanol comes from electricity produced by a traditional power plant the energy lost and net gain in pollution is tremendous. Add to energy production and transmission losses the fact a gallon of ethanol has about one third the energy density of a gallon of gasoline. Making a fuel like ethanol that delivers less energy per unit mass and in the process of manufacture and delivery produces more pollution and wastes more energy than the fuel it replaces makes absolutely no sense. If ethanol is to be a viable fuel alternative its manufacture must necessarily be hydrocarbon independent to make any sense at all.
As things stand now it makes more energy and environmental sense to burn a fuel at a personal vehicle than waste energy from remote traditional power plant to power it. This is especially true when one considers recent advancement in hybrid fuel-electric vehicles. These marvelous machines actually increase efficiency and lower emissions instead of substituting a poorer, energy wasteful, pollution increasing fuel or energy source. What applies to ethanol also applies to battery powered electric vehicles that get the majority of their energy from a traditional power plant. A pure electric vehicle getting its energy from a traditional power plant wastes more energy and pollutes more than any equivalent gasoline burning vehicle. Just follow the energy.
Energy alternatives to hydrocarbon fuels have a place and will become an important part of our energy mix but to fairly examine the merit of any energy source one must examine how it gets to the end use. Add to this problems inherent to the technology and industry necessary to produce and deliver the energy. For example, folks love to sing the praises of electric vehicles and yet completely ignore the fact lead-acid batteries (and all forms of batteries I am aware of) are an extremely dirty heavy industry with significant pollution and disposal problems. Battery technology is no less a hazard and environmental problem (and is probably more so) than the refinement, production, storage and delivery of diesel or gasoline fuel.
(On a side note, Mr. Watts recently noted the myth that gasoline burning vehicles are likely to blow up in a wreck as Hollywood likes to portray. Now think of an accident scene awash in acid and fumes from battery powered electric vehicles… and then think of how Hollywood might treat such a scenario loaded with gasoline, diesel, electric and hybrid vehicles in an explosion of mayhem and disaster — it boggles the mind.)
Anyway, my point is that most, if not all, claims of “low pollution”, “zero pollution” and “environmentally friendly” are trivially false (if not merely overstated) and all one has to do is “follow the energy” to see it.
It is highly unlikely that this compressed air vehicle has any pollution advantage over a internal combustion gasoline engine if you trace the energy path from source to end use.