diy solar

diy solar

Charging AA & AAA for Amish community

Natty said:
So you are thinking something like this-

shaft > car alternator > 12v battery (like a car battery??) > CITYORK 12 Slot LCD Smart Rechargeable Battery

Any fuses along the way?
Click to expand...

Yep.
Fuses between alternator and battery (based on size of alternator) and fuse between battery and charger should do it.
Another benefit of the car battery is you can use it to power the AA chargers quite a bit before needing to run the alternator.

What I don't know is what the minimum alternator rpm that is needed to generate a usable charge current.
 
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Interestingly, if it is a normal car alternator, generally you don't put a fuse or breaker between it and the 12 volt battery if at all possible.

If it is a large output alternator and a large battery bank, then it gets tricky to pull off.

The reason is that if there is anything that cuts the wire connection between the alternator and battery while it is spinning - it will blow everything out due to surge currents.

For this project, try to use an alternator that is 80 amps or so, not 300 amps.
 
Natty said:
So are you suggesting-

car alternator > 50Ah+ 12V battery (AGM or SLA preferred) > 8-40V to 12V regulator (Buck Boost Converter) > Two chargers (MiBOXER 8-Bay Smart Charger)

I like the versatility of the charger you suggested. thank you
Click to expand...

Yep, but that's not a charger. It just provides a consistent 12V output vs. the alternator/battery variable voltage. Probably not even needed, but 12V stuff doesn't always like 14+V seen during charging.

I personally have the MIBOXER charger, and it's extremely useful for NiMH AAA and AA as well as 18650 cells. It does require a bit of configuration though (2 buttons to press). Can easily get AA charged in 2h by configuring for 1A charging vs. the 500mA of the other and 4-6h of charging.
 
HarryN said:
For this project, try to use an alternator that is 80 amps or so, not 300 amps.
Click to expand...

I agree that smaller is better in this case.
As for the alternator to battery fuse, that is debatable. I have seen them used (as long as it's rated higher than the alternator output).
 
Texas-Mark said:
I agree that smaller is better in this case.
As for the alternator to battery fuse, that is debatable. I have seen them used (as long as it's rated higher than the alternator output).
Click to expand...

You are right - the fuse or breaker has to be higher and not just a little higher. I have seen alternators put out nearly 2x their ratings during rpm changes even with a fairly sophisticated alternator controller in place. Breaker tripped - alternator and all associated equipment was destroyed instantly.
 
Texas-Mark said:
Not needed though for this, since the battery will keep the voltage within the voltage range of the AA charger.
Click to expand...

For the cityork chargers I would agree as they are supplied with a 12V socket adapter, but I don't necessarily agree with it for the chargers I linked.

HOWEVER, I just found reference in the ad that it is "car charger" compatible, so I would assume there's a similarly available plug, and the 12V converter is not necessary.
 
sunshine_eggo said:
...but I don't necessarily agree with it for the chargers I linked.

HOWEVER, I just found reference in the ad that it is "car charger" compatible, so I would assume there's a similarly available plug, and the 12V converter is not necessary.
Click to expand...

I did not initially see the one you linked. It does have more types of batteries that it can charge, so that is a plus. And yes, I see it says car compatible. I think most if not all that are 12V input will work fine within the car battery voltage range (even when the alternator is charging it).
 
There's an off grid Mennonite community near me. One house has an odd looking windmill on an old school Aermotor water pumping windmill's tower. One day I finally saw them outside so I stopped by to chat. Very friendly folks.

Turns out the windmill is an air compressor made by Bowjon (maybe?). They are using used 500g propane tank as compressed air storage tank and converted all the power tools in the shop to run off of a belt and line shaft system.

There was compressed air engine somewhere but I didn't see it. The shop was full of modern Craftsman power tools like table saws and drill presses that that started off their life as standard electric tools but had been converted to run off the line shaft via leather belts. It felt like a factory from 1885 but in the X-Files.

The windmill with a 8' diameter or less was maybe 5' above the trees that it is was in the middle of failed to reliable (ever?) keep the tank filled so they were a gas powered compressor to fill up the air storage tank now.

This almost certainly resulted in a net system efficiency of less than 1%. Use a IC engine > compress air > store it >send it to the air engine >then deliver power it via a line shaft. WOW?!?! Solar PV would change thier life was all I could think.

When I suggested that we could somehow come up with a way to do it with solar it was shot down. Now I wasn't suggesting batteries or inverter etc, just a solar panel turning an electric motor on the air compressor. Knowing I was on thin ice I cordially asked if they could reference a place in scripture that forbade this naively thinking I could find a work around. All they could say "it's what the preacher says" so I dropped it immediately.

Mind numbingly numbers of contradictions I could see. They can use electricity at thier businesses but not at home. They can't own a car but can get a ride in one to fill up a gas can at a gas station that needs electricity to pump gas. Very interesting day.
 
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If you are looking for a comparison of AA and AAA batteries, this guy has done a lot of testing for us all.

Very solid information on various ones for high output vs high capacity type cells and their cycle life.


Harry
 
Smeeg said:
bosch vw generator id use a generator from a old VW beetle it can be rebuilt & is bulletproof can be found for $100 ish you will also need the Bosh voltage regulator. To a car battery enloops are considered the gold standard amazon brand nihm are rewrapped enloops FYI
Aftermarket version I’d try & find a used bosh
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I like where your head is at on this suggestion. So it is a generator huh? They should be able to stockpile a few of them at that price.
 
so current configurations is-

Aftermarket VW Generator (bosh)> cable type? > fuse? (if so type?) > 50Ah+ 12V battery (AGM or SLA preferred) > some kind of guage to show charge? > 8-40V to 12V regulator (Buck Boost Converter) > fuse? > Two chargers (MiBOXER 8-Bay Smart Charger)

I like the VW generator, probably because I am old.

I could make lamented directions, with pics, to show how to orient the polarity (if I am saying this right) bassed on what I saw on YouTube

Thank you for everything. Please keep suggestions coming. In this area, please think of me as a child
 
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Natty said:
so current configurations is-

Aftermarket VW Generator (bosh)> cable type? > fuse? (if so type?) > 50Ah+ 12V battery (AGM or SLA preferred) > some kind of guage to show charge? > 8-40V to 12V regulator (Buck Boost Converter) > fuse? > Two chargers (MiBOXER 8-Bay Smart Charger)

I like the VW generator, probably because I am old.

Or should I just go with a Golf cart generator ? So then they would not have to worry about setting the poles when they replace them

Am I overcomplicating this? Is there a generator for 12v that is bulletproof... and cheep? Maybe capable of being rebuilt?

Thank you for everything. Please keep suggestions coming. In this area, please think of me as a child
Click to expand...

Pretty sure your going to need Bosch voltage regulator (can be found cheaper)
I don’t think the buck/boost converter you linked is right or necessary for this application but could be wrong
 
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HarryN said:
For this project, try to use an alternator that is 80 amps or so, not 300 amps.
Click to expand...
The alternator will use a lot of power you need to make sure it won’t use enough power to jeopardize what they need the motor for. I am understand a standard alternator can use 3-5 horsepower when charging a optimally discharged battery.
 
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