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Discussion Starter · #1 ·
Trying to figure out some type of a manuel generator to supplement solar battery charging.

I want to power a freezer. (115 volts / 5 amps) I have a emergency battery thing from Costco. Has a plug outlet (12v / 400 amp I think, jumper cables ECT.) and I saw a 750 watt converter at Sam's Club. So from my beginner electrical understanding, 115 x 5 = 575 watts.

Regardless if that will work or not. I want to know how to charge a battery from a manuel crank. Can I just get a motor to something, put it on a crank, and hook up the red and black wire to the battery? Where would I get it? Harbor freight?
 

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You won't be able to generate enough manual crank power to charge the battery fast enough to keep up with a freezer. You can keep up with an LED flashlight, or a radio, but you'd be on a bicycle or a rowing machine to have a chance at doing anything substantial.

A normal household circuit is 15 amps. The freezer is about 1/3 of the load of a single circuit. That's a very serious load to run off a 12v battery.

Also, when the condenser motor on the freezer kicks on, it will draw a few times more power than steady-state running (Ever hear a motor buzz like a "whoomp" sound when it kicks on? It's working very hard and drawing a lot of current for a 1/2 second or so). These power spikes are handled by normal A/C power with just a voltage drop. Your inverter won't be able to handle these very well, if at all. Batteries aren't very good at running motors. They're better at running electronics.

Not that it won't work, but I'd buy a heavy-duty 1000 watt inverter plugged into a heavy duty deep cycle 12v battery made for boats or RV's. Maybe wire a few of them together in parallel to give you more capacity (run longer before going dead).

A setup like this will cost a few hundred dollars ($100-$300 for the inverter and maybe $100-$150 per 12v battery, plus wiring. And you'll need a trickle charger / maintainer that runs off A/C. That's around $50.). It might be worth a shot. And then it's only a matter of probably a few hours, if that, before the batteries die. The good news is the freezer's motor probably doesn't have to run constantly to keep the contents cool, so a setup like this might keep stuff cold for a few days if you keep the door shut? Just guessing on that.
 

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One more note. I setup a system similar to this to run a sump pump when the A/C power was out. It worked, but I bought a very good Triplite inverter that cost several hundred dollars, and I wired two batteries together for higher capacity. Even then, I was taxing the inverter pretty good because a sump pump motor creates a current spike when it kicks on, just like a freezer does. I bet I spent $500 on that setup.
 

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Discussion Starter · #5 ·
You seem like a smart guy. Thank you for the info.

While waiting for a response I was doing more research. The deep cycle is know obviously the way to go. My intent on the manual power is to maybe supplement solar charging. Or just to know how I guess.

If you have time give me or input on this:
I am planing to hook up 1-2 solar panels in my back yard to a charge controller, to 1-2 deep cycle batteries, to 750-1000 inverter. This is to run a back yard fountain and low voltage landscape lights. I can justify to wife because it will save money (maybe) and have some type of system in place for emergencies.

It would be great to somehow run a 1400 watt coffee maker but I think that my be to much? Maybe I could do 3 batteries and a better inverter, but I don't know if the solar could keep up.
 

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It would be great to somehow run a 1400 watt coffee maker but I think that my be to much? Maybe I could do 3 batteries and a better inverter, but I don't know if the solar could keep up.
Good grief man, a coffeemaker? Just heat water with fire. That's a lot of draw to put on a battery system just to do something that's more efficiently done some other way anyway.

As for the freezer, it's going to take a fairly large system to power it. Are there other food preservation methods that would work for you instead? Dehydration, home canning, smoking, curing, etc?

When I came to that part, I just planned around power alltogether and came up with non electrical alternatives for everything I needed to do.
 

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Discussion Starter · #7 ·
I know the coffee/freezer is dumb. I just wanted to use the power to save money now, then be able to use it more effectively to when SHTF. I live in LA and I fear fire would draw people if it were bad enough. Just need to run a electric stove for cooking/boiling water. The one I have is 1400 watts.
 

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I know the coffee/freezer is dumb. I just wanted to use the power to save money now, then be able to use it more effectively to when SHTF. I live in LA and I fear fire would draw people if it were bad enough. Just need to run a electric stove for cooking/boiling water. The one I have is 1400 watts.
Here's a little math to put this in perspective for you.

If it's a stove it's probably 220v.
1400W/220v = 6.63A (amps, *at 220v*, that part is important)

When you lower the voltage to 12v you have to raise the current to get the same amount of work done (work = watts... roughly).

That same 1400W at 12V looks like this:
1400W/12v = 116A
116 amps... from a car battery.

How long do you think that'll last?

As MikeK said, burn wood. Or, if you want heat (for cooking) that you could store and not attract bugs, store some charcoal briquettes. We get ice storms that knock out the power once in a while. I have a few extra bags in the garage.
 

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There are some generators that are set up on a bicycle. Takes a lot of running for a little amount of electricity.
The average guy on a bicycle puts out 100 to 150 watts on a continuous basis, while the Lance Armstrong types can put out 300 to 400 watts continuously. Professional sprint cyclists can put out over 1500 watts for a few seconds.

Edit to add: Here's a link to a power output graph of a hot-shot criterium racer:
http://www.fascatcoaching.com/criteriumracing.html
 

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Manuel Generator.... that's an illegal alien, right, or a prolific couple in Mexico... As for manual generators... they are all tiring. Falling water works the best.
i was about to say there should be some accent marks over the "e"'s in there.
 
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