Compressed Air Car
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positronicle
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Chris Smith
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There is no reason to make an Air Powered car.
If you desire to waste energy in a vehicle, simply drive with the hand brake on.
No need to waste the engineering or energy the air will accomplish when a hand brake will do the same thing.
The concept here is saving energy, not finding new ways to first make energy, then waste it using a medium like air trying to get it from point A to point B.
Its not only old it a waste of time because its inefficient.
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"Isaac Newton got a free lunch when that apple fell out of the tree"
That means there is no free lunch in physics.
Isaac is a seperate issue.
If you desire to waste energy in a vehicle, simply drive with the hand brake on.
No need to waste the engineering or energy the air will accomplish when a hand brake will do the same thing.
The concept here is saving energy, not finding new ways to first make energy, then waste it using a medium like air trying to get it from point A to point B.
Its not only old it a waste of time because its inefficient.
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"Isaac Newton got a free lunch when that apple fell out of the tree"
That means there is no free lunch in physics.
Isaac is a seperate issue.
The way I see is that they (the creators) believe that compressed air is a viable storage medium for kinetic energy. Their goal may be to save energy but it may also be to use greener sources of energy. An Air compressor can be run on any number of intermittent/irregular sources of primary energy not excluding wind, wave, sun, electric (timed to low rates), petro fuels (O'l standby) so long as local storage is available until you need it in the car.
Compressed air can be converted to motion is several ways. In the case of direct conversion of air flow to rotational motion; it's inefficient requiring an impeller (air tool style) that would be very inefficient for this application because of the volume of air required to make torque. This type of motor would require the analogous current source to operate if it were electric.
However, air pressure to linear motion as in a piston, is somewhat efficient not requiring leakage around the cylinder and using mainly the stored pressure (not air flow) to develop its torque (like a voltage source as it would). Sure, some air would be expelled but designers would have more room to play with cylinder sizes to mange that. Higher pressure would allow for lower rotational speeds and less air volume expelled.
Also the lower pressure expelled air could be recaptured to run say the brakes (well, maybe not) or power steering and of course the climate controls. Remember those old Mercedes with the pneumatic door locks.
I don't care to go into the physics to discover how valid their claims are but I'm also not going to stereotype it away. The alternatives are that it's all a bluff to get publicity or they are truly incompetent.
Compressed air can be converted to motion is several ways. In the case of direct conversion of air flow to rotational motion; it's inefficient requiring an impeller (air tool style) that would be very inefficient for this application because of the volume of air required to make torque. This type of motor would require the analogous current source to operate if it were electric.
However, air pressure to linear motion as in a piston, is somewhat efficient not requiring leakage around the cylinder and using mainly the stored pressure (not air flow) to develop its torque (like a voltage source as it would). Sure, some air would be expelled but designers would have more room to play with cylinder sizes to mange that. Higher pressure would allow for lower rotational speeds and less air volume expelled.
Also the lower pressure expelled air could be recaptured to run say the brakes (well, maybe not) or power steering and of course the climate controls. Remember those old Mercedes with the pneumatic door locks.
I don't care to go into the physics to discover how valid their claims are but I'm also not going to stereotype it away. The alternatives are that it's all a bluff to get publicity or they are truly incompetent.
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Chris Smith
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By what ever means you intend to make compressed air, you simply take that energy and directly apply it to the motivation of the wheels using electrons.
Electrons store just as easy as air only its smaller, lighter, and cheaper.
What you don’t do is make a generator running a motor running a generator simply because in doing so you lose at each transaction, the same as you do when making compressed air and then trying to utilize it.
Directly apply the energy needed to create air into the transmission and bypass the wasteful practice of first creating air pressure, then consuming it at a loss.
It doesn’t travel from point A to point B any better than electrons do. It does worse.
Electrons can directly make EMF [electro motive force] which can be consumed by the wheel making electrons to motion a two part step.
With air, electrons or the windmill are first needed to make compressed air using a motor driving a compressor or a blade driving a compressor.
Then you need to store it in a very heavy cylnder and lose the heat energy it contains from making it in the process, thus losing some of its energy in the process.
Then you have to lug aroung this extra weight as part of the condition of the storage tank.
Pound per CC of material in a air tank VS a cap is all too obvious.
Then the air is moved down a line at a loss to a mechanical device to absorb the air and then turn it back into motion of the wheels.
The inefficient air moving from point A to B, and then the motor absorbing it to run a wheel.
Electrons can be made from the sun or turbine, part one, and stored in a cap, point two, then used down a line, part three, and in turn a wheel, part four.
Simalar to compressing.
In many ways they too are four parts in the equation but compressed air VS stored electricity is high friction VS low friction.
High engineering VS low tec.
The friction of mechanic objects VS the friction of the electron in a wire.
One requires great engineering work where as the other requires wire and a few operating transistors.
There are no free lunches in physics, and losing energy is much easier accomplished by placing your foot on the brake peddle and throttle at the same time
Electrons store just as easy as air only its smaller, lighter, and cheaper.
What you don’t do is make a generator running a motor running a generator simply because in doing so you lose at each transaction, the same as you do when making compressed air and then trying to utilize it.
Directly apply the energy needed to create air into the transmission and bypass the wasteful practice of first creating air pressure, then consuming it at a loss.
It doesn’t travel from point A to point B any better than electrons do. It does worse.
Electrons can directly make EMF [electro motive force] which can be consumed by the wheel making electrons to motion a two part step.
With air, electrons or the windmill are first needed to make compressed air using a motor driving a compressor or a blade driving a compressor.
Then you need to store it in a very heavy cylnder and lose the heat energy it contains from making it in the process, thus losing some of its energy in the process.
Then you have to lug aroung this extra weight as part of the condition of the storage tank.
Pound per CC of material in a air tank VS a cap is all too obvious.
Then the air is moved down a line at a loss to a mechanical device to absorb the air and then turn it back into motion of the wheels.
The inefficient air moving from point A to B, and then the motor absorbing it to run a wheel.
Electrons can be made from the sun or turbine, part one, and stored in a cap, point two, then used down a line, part three, and in turn a wheel, part four.
Simalar to compressing.
In many ways they too are four parts in the equation but compressed air VS stored electricity is high friction VS low friction.
High engineering VS low tec.
The friction of mechanic objects VS the friction of the electron in a wire.
One requires great engineering work where as the other requires wire and a few operating transistors.
There are no free lunches in physics, and losing energy is much easier accomplished by placing your foot on the brake peddle and throttle at the same time
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positronicle
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Chris Smith
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positronicle
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positronicle
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Chris Smith
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76 KG of super caps is worth one HP for one hour.
A 100# air tank at 2000 psi may get you a few yards at best delivering one full HP into the most efficient type of air motor.
2000 ci of air tank at 140 times atmosphere [2000 psi] is about 285,000 ci or in a Brigs and Stratton motor of 5 ci per stroke is about 60,000 strokes divided by 60 seconds is 6000 rpms. A good cough to life before it dies a minute later. And there was no gas burning to expand the air so the motor can produce the normal HP?
As for lasting:
The air motor is a complete friction driven animal, it wears out.
As to the electric motor, electrons dont wear out, only the bearings do the same as the motor does but by far less. [the motor has vanes, cylnders, gears, etc]
As to super caps, they too also last as long as the air tank, which is much longer than the air motor parts.
From the web...../ AND Volumes are spoken here....
efforts to find other applications for compressed air storage are hampered by its poor energy density, slow response times and storage requirements ...the technology has a higher initial cost than battery-based energy storage.
During off-peak hours, power is used from the grid to compress air and store it in wells or aquifers. Then, during peak hours of energy demand, the compressed air is heated with natural gas and used to drive expansion turbines to generate hundreds of megawatts of electrical energy.
Despite interest in the technology, no company has yet put a vehicle using this technology into mass production.
Having solved most of the high pressure storage and handling problems, the main remaining disadvantages are related to the thermodynamics of air compression and expansion, the consequent temperature changes, and the resultant heat transfers.
At the supply station, compressing the air heats it, and if then directly transferred in a heated state to the vehicle storage tanks will then cool and reduce the pressure. If cooled before transfer, the energy in this heat will be lost unless sophisticated low grade heat utilization is employed (see cogeneration).
Within the vehicle, expansion and consequent pressure reduction in the throttle or engine chills the air, reducing its effective pressure. Addition of ambient heat will increase this pressure and this addition leads to a more complex propulsion system. While an attempt was made in the Nègre system to warm the air in a long portion of the stroke at top dead center, it appears that this scheme has been abandoned due to inherent imbalances causing unacceptable levels of vibration.
Passenger compartment heating is more difficult since the propulsion system does not provide a source of waste heat. Some form of heat pump device would probably be required.
*************
Gasoline motors waste 75 cents out every ever dollar in the form of heat out of the tail pipe and radaitor. [50/25]
This thermal energy can be conserved back into electricity, air pressure, and all sorts of energy forms.
However, air contains no energy until something else imparts its energy towards the air.
Same goes for electricity, but it wears better, last just as long, weighs less, and doesnt require further mechanical wear and tear to impart its energy back into the world.
A 100# air tank at 2000 psi may get you a few yards at best delivering one full HP into the most efficient type of air motor.
2000 ci of air tank at 140 times atmosphere [2000 psi] is about 285,000 ci or in a Brigs and Stratton motor of 5 ci per stroke is about 60,000 strokes divided by 60 seconds is 6000 rpms. A good cough to life before it dies a minute later. And there was no gas burning to expand the air so the motor can produce the normal HP?
As for lasting:
The air motor is a complete friction driven animal, it wears out.
As to the electric motor, electrons dont wear out, only the bearings do the same as the motor does but by far less. [the motor has vanes, cylnders, gears, etc]
As to super caps, they too also last as long as the air tank, which is much longer than the air motor parts.
From the web...../ AND Volumes are spoken here....
efforts to find other applications for compressed air storage are hampered by its poor energy density, slow response times and storage requirements ...the technology has a higher initial cost than battery-based energy storage.
During off-peak hours, power is used from the grid to compress air and store it in wells or aquifers. Then, during peak hours of energy demand, the compressed air is heated with natural gas and used to drive expansion turbines to generate hundreds of megawatts of electrical energy.
Despite interest in the technology, no company has yet put a vehicle using this technology into mass production.
Having solved most of the high pressure storage and handling problems, the main remaining disadvantages are related to the thermodynamics of air compression and expansion, the consequent temperature changes, and the resultant heat transfers.
At the supply station, compressing the air heats it, and if then directly transferred in a heated state to the vehicle storage tanks will then cool and reduce the pressure. If cooled before transfer, the energy in this heat will be lost unless sophisticated low grade heat utilization is employed (see cogeneration).
Within the vehicle, expansion and consequent pressure reduction in the throttle or engine chills the air, reducing its effective pressure. Addition of ambient heat will increase this pressure and this addition leads to a more complex propulsion system. While an attempt was made in the Nègre system to warm the air in a long portion of the stroke at top dead center, it appears that this scheme has been abandoned due to inherent imbalances causing unacceptable levels of vibration.
Passenger compartment heating is more difficult since the propulsion system does not provide a source of waste heat. Some form of heat pump device would probably be required.
*************
Gasoline motors waste 75 cents out every ever dollar in the form of heat out of the tail pipe and radaitor. [50/25]
This thermal energy can be conserved back into electricity, air pressure, and all sorts of energy forms.
However, air contains no energy until something else imparts its energy towards the air.
Same goes for electricity, but it wears better, last just as long, weighs less, and doesnt require further mechanical wear and tear to impart its energy back into the world.
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positronicle
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Chris Smith
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The air in the internal combustion engine gives you nothing.
And it fact it takes energy to draw it in in the first place.
The exothermic energy of the air is a bi product of combining the perfect ratio of air to fuel, then expanding and pushing that energy in the engine at a pathetic rate of 75% loss, and mean while all of the gas is doing all of the real the work. [Energy] The air comes along for the ride because it has no energy on its own.
Air in the engine is a medium to transform some other form of energy and still they are both inneficient.
With out the exothermal energy of the gas, air is just short of useless, except for the energy you wasted making the compressed air in the first place.
Zero return with out gas and a loss to begin with.
And even then that is ineffective, costly, bulky, heavy, and all the other reasons to chose molasses, sea water, or liquid sodium as a energy transfer source above the compressed air source any day.
If your sole purpose in life is wasting energy, just put your foot on the brakes, its cheaper and more hi tek.
And it fact it takes energy to draw it in in the first place.
The exothermic energy of the air is a bi product of combining the perfect ratio of air to fuel, then expanding and pushing that energy in the engine at a pathetic rate of 75% loss, and mean while all of the gas is doing all of the real the work. [Energy] The air comes along for the ride because it has no energy on its own.
Air in the engine is a medium to transform some other form of energy and still they are both inneficient.
With out the exothermal energy of the gas, air is just short of useless, except for the energy you wasted making the compressed air in the first place.
Zero return with out gas and a loss to begin with.
And even then that is ineffective, costly, bulky, heavy, and all the other reasons to chose molasses, sea water, or liquid sodium as a energy transfer source above the compressed air source any day.
If your sole purpose in life is wasting energy, just put your foot on the brakes, its cheaper and more hi tek.
I'm sure he was referring to the lifetime of the storage tanks vs the replacement rate of depleated batteries.Batteries don't last as long as air tanks. Weigh a lot more too.
For example the plug in module for the Prius (hymotion) is $9,500, lasts 600 cycles or approximately 2 years at which time it needs to be replaced. Thats a Li Polymer battery.
The lifetime of a NiMh is a bit better for the price of more weight and less cost but they won't last forever and the replacement cost and frequency is uncertain (it certainly isn't discussed any hybrid car broschures)
Barring a puncture , the tank should last the life of the vehicle.
An all electric vehicle even today has aweful range and overnight recharge times. Not terribly practical by itself either. I don't think even its creators see it as supplanting Electric or even CNG as an alternative power source (careful not to say fuel). Just an alternative. To be fair, some of their claims are a bitmoutlandish. A refill for ~$2 for 300km range seems optimistic.
Without naysayers, what would motivate all those young engineers who don't know it can't be done. History has no shortage of examples.
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positronicle
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Chris Smith
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The life of the battery may be limited,.... as we move towards the super cap.
However, 600 cycles and thousands of miles sure beats a few yards travel for of a compressed Air tank.
Apples and oranges never were meant to be compared.
Air is a medium in the internal combustion engine.
First it is air or oxygen and its components, then its combined into a controlled explosion of exothermic reaction [energy] and that then turns into CO that now expands. Air with heat pushes the piston, not cold air. Hot air contains energy, cold air barely move a snails butt compared to hot expanding air.
It not because of the air it’s the exothermic reaction of the gasses that form energy that is usable.
The CO does the real work at a 75% loss and meanwhile the heat isn’t captured or used, it is dumped out the exhaust and tail pipes.
To think there is a value to the air as your power source here is ludicrous. First you have to waste energy just to get it, then if you don’t apply the exothermic catalyst gas, you only get a loss.
It’s the exothermic reaction with air, while the CO expands thanks to the combustion reaction.
You can mix gas and air to heat water, its called a steam engine. Air in the case of the motor is not the energy source, it’s a exothermic combination between two mediums.
Using expanding CO and heat to power the piston is how a motor functions. Not by applying compressed air and waiting for it to move.
Compressed air might spin a toy pin wheel for a few hours but it will never be stored like gasoline at 17,000 BTUs worth of power per pound, or even near the electro storage density of any type of battery or cap.
60 pounds of gas will propel a car by consuming 14 times that in air, [840] then it will transform this mixture into hot CO to push a piston and waste 75% of its energy in doing so.
Gasoline can afford to waste these amounts of energy, compressed air on the other hand doesn’t have the luxury equal in BTUs, or anything near the combustion engine let alone the electric storage mechanism.
However, 600 cycles and thousands of miles sure beats a few yards travel for of a compressed Air tank.
Apples and oranges never were meant to be compared.
Air is a medium in the internal combustion engine.
First it is air or oxygen and its components, then its combined into a controlled explosion of exothermic reaction [energy] and that then turns into CO that now expands. Air with heat pushes the piston, not cold air. Hot air contains energy, cold air barely move a snails butt compared to hot expanding air.
It not because of the air it’s the exothermic reaction of the gasses that form energy that is usable.
The CO does the real work at a 75% loss and meanwhile the heat isn’t captured or used, it is dumped out the exhaust and tail pipes.
To think there is a value to the air as your power source here is ludicrous. First you have to waste energy just to get it, then if you don’t apply the exothermic catalyst gas, you only get a loss.
It’s the exothermic reaction with air, while the CO expands thanks to the combustion reaction.
You can mix gas and air to heat water, its called a steam engine. Air in the case of the motor is not the energy source, it’s a exothermic combination between two mediums.
Using expanding CO and heat to power the piston is how a motor functions. Not by applying compressed air and waiting for it to move.
Compressed air might spin a toy pin wheel for a few hours but it will never be stored like gasoline at 17,000 BTUs worth of power per pound, or even near the electro storage density of any type of battery or cap.
60 pounds of gas will propel a car by consuming 14 times that in air, [840] then it will transform this mixture into hot CO to push a piston and waste 75% of its energy in doing so.
Gasoline can afford to waste these amounts of energy, compressed air on the other hand doesn’t have the luxury equal in BTUs, or anything near the combustion engine let alone the electric storage mechanism.
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