I have not heard about an wind/air turbine used to refill an air compressor (without electricity). Not sure how that would work, but I'm very interested in learning if anyone has background here.
A wind turbine turns rotation into electricity.
A motor turns electricity into rotation.
A compressor uses rotation to compress gas.
You can remove the electricity between stages 1 and 2.
It's easier to perceive when you think about a massive turbine that can grind out a ton of electricity and power a compressor that by default produces a lot of air pressure.
These tools are really neat to me. I love the idea of things like a hand crank radio, pulleys, and long levers.
Presumably you could fill the tire of a transport truck with the bulb from a blood pressure cuff and a lot of time, but it's not intuitive to me what the mechanics are in between those two things.
Um. Yes, you can. It just might take a little while. You can fill 100 psi road bike tires with a hand pump. A 30-40 psi car tire is not a problem.
yeah the pressure isn't a problem, the volume can wear you out though :)
I use bike pumps a lot, but only on bikes, so I've never experienced this.
That's what the compressed gas is - it's potential energy. It's like a battery.
> Like how I can't fill my car tire with my bike pump.
Why not? Because you can't pump hard enough and it's not strong enough to hold the pressure needed? You can build a stronger pump, and you can use a lever or gears (same thing really) to compensate for your strength if you can't pump any more.
> Presumably you could fill the tire of a transport truck with the bulb from a blood pressure cuff and a lot of time, but it's not intuitive to me what the mechanics are in between those two things.
Again that's just a 'lever' problem - you can't squeeze the bulb hard enough, so add a lever (and you may need to make the bulb stronger.)
The sorely missing bit is the equivalent of those amazing DC/DC step-up/down voltage regulators that have revolutionized the application of electricity in recent decades (all the way from tiny electronics to massive HVDC networks), and/or an equivalent of the AC transformers that fulfilled a similar role before. Actually AC is missing in its entirety, there's just no practical way of transmitting power via soundwaves.
The closest pneumatic equivalent to DC-DC converters are coupled turbines, e.g. turbochargers or high bypass turbojets. But those are not just far beyond households appliance scale, they are also limited to the high mass-flow/low pressure differential, but practical applications of pneumatic storage are the opposite.
Interestingly, there is actually a hydraulic mechanism that's the equivalent of a boost converter with inductor, diode, and switching element:
https://en.wikipedia.org/wiki/Hydraulic_ram
It translates a low-pressure fluid with continuous flow into periodic high-pressure impulses. The inertia of the fluid is the hydraulic equivalent of the inductor, and a switching element (valve) closing suddenly causes a spike in pressure as the water decelerates suddenly, equivalent to a voltage spike as an inductor "wants to keep the current flowing".
But it usually operates with water, which has much higher density (hence inertia) than air, so it might not be very efficient (or might require much higher flow rate) in a pneumatic version.
As others have pointed out, you can! If you're rather patient. They've even got compatible valves!
And you can think of a pneumatic tire as a kind of battery -- potential energy is roughly the volume times the pressure differential.
Energy is force times distance. If you can only exert a tiny force, you can compensate with enough distance, providing the losses in the system aren't too great.
Edit: I must have skipped over your last sentence. I thought you wanted all those electrical steps for some reason!
They were not shunning technology it was just a cheaper option than running power out there or batteries.