Howdy folks,
This is a fascinating discussion. As a new member here, I have only now noticed this thread.
My power is all generated here on my little farm. I have a number of homemade wind turbines and a couple of homemade backup generators.
Battery maintenance is an important issue, as failure to take due care results in expensive losses.
In an attempt to partially resolve this issue, I built an extra big wind turbine. it stands 30 feet tall and carries a rotor that is 20 feet in diameter.
It delivers electricity at 400VAC by 3 phase. Just lately, I added a four cylinder car engine that I converted into a compressor. Now, I get compressed air at 125 PSI whenever the wind is blowing. The air is stored in a series of tanks that give me a total of 400 litres of capacity.
Since this machine operates so effectively, I plan to add more air storage tanks to the system.
Ultimately, this part of the windmill project will be controlled by a little computer, so it will be able to 'look after itself'.
Right now, it's manually operated. I have to operate the electric clutch to engage / disengage the compressor, based on air demand, tank status and electricity usage.
To use some of the energy that is so stored, I built a little air engine.
It's the first I have ever built, so I started small. It has only one cylinder, and that is only 1 inch in diameter. The piston travel 1.5 inches and the whole thing delivers a whopping 40 watts!
I plan to build something better soon. Perhaps one that will deliver 1HP of power at the shaft. Using a home built genny on the shaft, I may expect 500 Watts of electrical energy

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So, one can run an 'engine' inside the house and benefit from the exhaust gases
I 'sniff' mine all the time
Best wishes,
Steve-tee.
Oh, by the way - the 'Vanadium Solution Redox Battery' may be worth having a look at also

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