"They get around 10% or less. Compressor's are inefficient because the heat the air while compressing it,"
To a point, but I think there is more to look at than just that. First those big old fashioned multieblade mills turn in low winds and have High torque, that is power to compress air. Not enough wind to get high rpms for battery charging. It really does not matter in this case what the inefficient percent is, because anything is 100% more than nothing right
Well you know what I mean anyway. Anything times zero is zero, so how would you really figure that then?
Also where/when is the heat? Sure grab a copper feed line after a compressor has pumped up 120psi and it is hot. But grab that same line around 20psi or 30psi and it's not as hot. So you could say efficiency is a graduated scale maybe, the higher the pressure the more heat created. Pump 40psi as you use 40psi and not allot of heat is created as I recall. Something like that, maybe it was only at 20psi. In other words use it as fast as it's made like a straight through shot and allot less heat is produced. On the other hand though, always build up pressure from 100psi to 120psi and you are always fighting yourself basically.
Basically you create heat when you compress a gas, but not when just moving it. At least not as much.
Feel the tank on a compressor after it ran from empty to full pressure, it is not hot, the small copper line at the compressor head is hot, perhaps we need a much larger line here to produce less heat?
Then also figure in all the losses with generating electric. Alternators, wires, batteries, self discharge, more wires, direct DC use or another loss at the inverter and more wires then AC use. No power in lower winds.
I think a mathematician would have a feed day here showing how you have to produce 10Kw today to have 600watts available tomorrow
Kinda like people tell me how inefficient wood heat is because you have to heat cold air from outside and blow hot air up the stack, but at the same time I have a $20 electric bill for the month and use $10 wood heat, they have really efficient electric heat with no losses of heating cold outdoor air nor the losses up any
stack but their electric bill is around $200 per month.
To me $30 per month is far more efficient than $200! I guess it all depends how you look at things too.
Now also think, to make $30 at $10 an hour I would have to work a little over 3 hours (got to figure losses for taxes) that's 1 drive to work and home, 1 lunch at work, one change of clothes etc.. (not even that, since the next 5 profit hours would also require the same, so it's more like 3/8 of each )
For them to make $200 at $10 an hour, well over 20 hours work, at 8 Hours a day that's about 3 days (24 for hours, don't forget taxes and such) so that's 3 times the driving to work, 3 times the lunches, 3 times the change of clothes etc...
Actually much much more, remember my $30 is only 3/8 of a day, their 3 days is 24/8ths of a day, 8 times as much!!!
Now I gave up 3 hours of my life to heat my home for 1 month, they gave up 24hrs of their life to heat their home. What is the total efficiency and who came out the best on this deal??
Also don't forget all that pollution created driving to work! Ok, 3/8ths by me 24/8ths by them figuring the same mileage's etc.. So I created less pollution here also.
Then you got the pollution actually heating the home, mine is burning wood at my house, theirs is a power plant somewhere burning coal. Mine has has no line losses either
Washing the 3/8ths of clothes I wore making the $30 and washing the 24/8ths of clothes they wore making $200 dollars
When people like me start knick picking things apart sometimes we can find TRUE ways to improve the math for efficiency
Tossing a chunk of wood in the fire while watching a movie or walking by to get coffee takes no countable time. Cutting wood (for me) is basically non existant. Cost is figured in the $10. I was already driving by the mill so I got 5-10 minutes time tied up for a months wood, waiting for it to be loaded.
Ok maybe BTU for BTU wood may not be as good as electric or propane heat for efficiency, but that's not all that is involved in the total picture is it
Pretty much about the same thing with anything else also!
Even compressing air VS and alternator