B Converting 10 PSI to Electrical Energy

AI Thread Summary
Converting 10 PSI of pressure into electrical energy involves understanding the relationship between pressure, volume, and energy. The discussion highlights that pressure multiplied by volume yields energy, and using compressed air to drive a generator can produce electricity, albeit with low efficiency. The efficiency of converting compressed air to electricity is generally less than 20%, making direct electrical supply a more effective option. The concept of using a balloon to create a repeatable energy cycle raises questions about practicality and efficiency, with suggestions that a more straightforward approach, like a stationary bicycle generator, would be more effective. Overall, the conversation emphasizes the need for precise context and understanding of energy conversion principles to achieve meaningful results.
bjAndrea
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This is not my subject, but I need to know if I can convert 10 PSI to energy. for example, If I have a permanent magnet motor rotate X time (RPM) to produce 10 PSI. Now Can I invert this process, if I have 10 PSI and let it pass on a permanent magnet motor, How much electricity will produce? in other words, the source of power is 10 PSI, anyone has the calculation, how much electric coil I need, size of the coil and the length, number of rotation per coil. etc. or just the output how much Amp
This is not my subject, but I need to know if I can convert 10 PSI to energy. for example, If I have a permanent magnet motor rotate X time (RPM) to produce 10 PSI. Now Can I invert this process, if I have 10 PSI and let it pass on a permanent magnet motor, How much electricity will produce? in other words, the source of power is 10 PSI, anyone has the calculation, how much electric coil I need, size of the coil and the length, number of rotation per coil. etc. or just the output how much Amp can produce by 10 PSI pressure, with a pipe of x size.
moreover, if I have 10 PSI continues pressure, I need to convert it to Amp. Anyone can help.
Regards
 
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Pressure times volume is energy. So you would need to multiply the pressure by the volume of air to get the energy.
 
You can use compressed air to drive a fan (wind turbine) to spin a generator to make electricity. Is that what you are asking about?

If you have a container holding 10 PSI compressed air, as soon as you start letting air out, the pressure starts falling and will no longer be 10 PSI.

Perhaps you can tell us what you are trying to accomplish, we can give better answers.
 
anorlunda said:
You can use compressed air to drive a fan (wind turbine) to spin a generator to make electricity. Is that what you are asking about?

If you have a container holding 10 PSI compressed air, as soon as you start letting air out, the pressure starts falling and will no longer be 10 PSI.

Perhaps you can tell us what you are trying to accomplish, we can give better answers.

Let assume we have a balloon and I have someone press this balloon the air going out of the balloon through a pipe and then motor to produce electricity, then the air goes back to the balloon when people step out of the balloon, this process is repeatable, the output of the pressure is 10 PSI. can I know how much I can make from this 10 PSI
 
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Are you looking for some kind of free energy project? If so, it is a topic not allowed on PF.
 
bjAndrea said:
if I can convert 10 PSI to energy.

If your motor can drive a compressor to produce a constant 10PSI then this could (allowing for some pretty low efficiency conversion) produce a smallish fraction of the electrical power out that was supplied to the original motor. This will be true for however much compressed air that your motor can supply.

Energy Out = Efficiency * Energy In.

Efficiency will always be less than unity and probably not more than 20%. Best to use the electrical supply you started with.

Unless you envisage storing the energy in the form of compressed air. In which case you may be better off to use a pneumatic motor directly to power your load. Batteries are usually the best solution although there are some other, more novel solutions about.

Every energy conversion and storage system loses you some energy.
 
bjAndrea said:
can I know how much I can make from this 10 PSI
Pressure times volume is energy. Again.
 
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bjAndrea said:
If I have a permanent magnet motor rotate X time (RPM) to produce 10 PSI.
The motor will make the pressure rise to 10 psi, but then it will have to be shut off if you want the pressure to stay at 10 psi.
 
@bjAndrea You really need to describe what machine or system that you are actually investigating. The answers you have been getting have covered a much wider field than necessary. If you want definitive answers you need to be more precise with the context of your questions.
 
  • #10
bjAndrea said:
Let assume we have a balloon and I have someone press this balloon the air going out of the balloon through a pipe and then motor to produce electricity, then the air goes back to the balloon when people step out of the balloon, this process is repeatable, the output of the pressure is 10 PSI. can I know how much I can make from this 10 PSI
Kind of like pumping a bicycle pump? That's not a very efficient way to make electricity from a person's work. A stationary bicycle directly driving the generator would be more efficient...

https://www.ilovebicycling.com/wp-content/uploads/2016/06/how-to-use-a-bike-pump.jpg
1572281600384.png
 
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D'you know, I think this is a bit of the dreaded energy harvesting idea. It does have all the characteristics. In what other scenario would people be treading on balloons to produce electricity?
 
  • #13
bjAndrea said:
No, this is not a free energy project, this is an energy conversion
What possible (useful) application would this have?
 
  • #14
sophiecentaur said:
What possible (useful) application would this have?
Does it matter? Even if it is just curiosity his question has an easy answer. ( which I have given twice now and he appears to have ignored twice )
 
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  • #15
bjAndrea said:
No, this is not a free energy project, this is an energy conversion
Fair enough. Can you explain in more detail how you intend the device to work? Do you understand what people said about needing a volumetric flow rate and do you know what it is for your device?

The difficulty with compressed air as a storage medium is that it is fairly low in efficiency; something like 50%.
 
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  • #16
sophiecentaur said:
D'you know, I think this is a bit of the dreaded energy harvesting idea. It does have all the characteristics. In what other scenario would people be treading on balloons to produce electricity?
It does, but the idea is so poorly described it is tough to tell. I wouldn't completely rule out compressed air energy storage at this point.
 
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