Off Grid Crypto Mining with 48V, system design

[PNPmacnab]

I just heard bitcoin payout just halved. Hopefully there will now be less mining posts.

[QuentinMedina]

One approach to achieve a higher capacity at 48V is to use 24V power banks in parallel and then wire them in series to reach 48V. This way, you can double the amp-hour capacity while maintaining the desired voltage.Regarding your solar panel choice, the Trina 410s seem like a solid option for your setup. They should provide enough power to keep your rig running smoothly.

Mod edit. Removed commercial hotlink.

[Fullblast]

The fridge is in my RV and I have no access to the plug, unless I tear up some panels and cabinets.


I found a pallet of 30 Solar World 280 watt mono panels that were manufactured in 2015 for a great price.Are these a decent brand for solar panels?

On the panels, the open circuit voltage of 39.5, short circuit current 9.71,max power point current 9.07

This is an 8400 watt system, I may add a few more to get 10kw and pair it with a 1000ah forklift battery.

What would be the max number of panels I could put on a 1000ah forklift battery without frying it?

Im still trying to figure out how many panels i can put on a 600v 80 amp mppt controller. If these panels are 9.71 amps each , can only put 8 on each controller. 8 would be 77.68 amps correct?

Others here said I can use 3 80 amp controllers for a 10kw system, but I don't understand completely.

I appreciate the help.

[SunEagle]

Okay thank you. I found where it says 439 watts.

So it would be 10.5kwh or 10536 watt hours.

I need to find a spec sheet for my fridge to give my daily kwh when accounting for the compressor kicking in and out.

Or get a Kill a Watt meter which will measure the watt hour usage of the load over any period of time desired.

[Fullblast]

Okay thank you. I found where it says 439 watts.

So it would be 10.5kwh or 10536 watt hours.

I need to find a spec sheet for my fridge to give my daily kwh when accounting for the compressor kicking in and out.

[SunEagle]

Maybe I wrote that wrong. If the fridge is 2.7 amps at 115v it is 310.5 watts.

310.5x24 is 7452 watts.

That's what the label inside the door says. I'm not sure if that is a 2.7 amp constant or when the compressor kicks in. I'm having a hard time trying to find energy consumption online for my particular Dometic rv fridge.


Does my math checkout? Thanks

No. when you multiply a number by another number you should use the labels. So 310.5 watts x 24 hours = 7452 Watt Hours or 7.45kWh.

But you are correct your frig may not use 2.7 amps continuously and the voltage may be different than 115V. So your kWh calculation may be off.

[Fullblast]

Do you really mean, AC is 13.5 kwHOUR daily if run 24 hours and the fridge is
7.5kwHOUR daily? My energy star fridge-freezer uses only 1 KWH a day.
Bruce Roe

Maybe I wrote that wrong. If the fridge is 2.7 amps at 115v it is 310.5 watts.

310.5x24 is 7452 watts.

That's what the label inside the door says. I'm not sure if that is a 2.7 amp constant or when the compressor kicks in. I'm having a hard time trying to find energy consumption online for my particular Dometic rv fridge.


Does my math checkout? Thanks

[bcroe]

The AC is 13.5 kw daily if run 24 hours and the fridge is 7.5kw daily.

Do you really mean, AC is 13.5 kwHOUR daily if run 24 hours and the fridge is
7.5kwHOUR daily? My energy star fridge-freezer uses only 1 KWH a day.
Bruce Roe

[Fullblast]

This is not about winning the lottery.

It's about monetizing surplus energy/passive income.

The 3250 watt mining rig is a really efficient one that I am considering buying.

Right now I have several 1350 watt rigs on full power, and 800 watts each on eco mode.


I see no reason why a 10-15kw solar system paired with a forklift battery can't power mining rigs during peak sun hours. They only need to be run 24/7 for max profit.


I know the best way to engineer a system is from the ground up on the loads you will be running. I have an RV, the fridge is 2.7 amps, and a 4.9 amp air conditioner.

The AC is 13.5 kw daily if run 24 hours and the fridge is 7.5kw daily. I'm not sure if those numbers are constant on the fridge, I do not use propane with it.

[azdave]

Well that does kind of depend on what your power company charges per KWH of usage. Another factor is how much DIY effort your willing to do.
If you are making your own packs from EV batteries you can get a pretty big bank of batteries for a fairly low cost but it's going to be a lot of work form start to finish.

That's why he should not expect to save on his electric bill going 100% off-grid in Texas compared to being on-grid, especially with the load requirements he is looking at.

[robbyg]

I don't get your comment about "except for saving on an electric bill". An off-grid system is not going to save you money compared to being on the grid.

Well that does kind of depend on what your power company charges per KWH of usage. Another factor is how much DIY effort your willing to do.
If you are making your own packs from EV batteries you can get a pretty big bank of batteries for a fairly low cost but it's going to be a lot of work form start to finish.

[azdave]

Whatever power I have left over (should) go to profit, on an otherwise unprofitable solar system, except for saving on an electric bill.

You say you need 3250 watts continuous power 24 hours a day for mining. Even with a large off-grid system in place you will not have that kind of "excess" power sitting around unused on most days. That is a major design parameter that must be factored fully, just like the A/C unit, refrigerator and the electric water heater you mention in your recent post. You would be far more likely to strike it rich by playing the lottery each week but as I always say, "You can't lose if you don't play".

I don't get your comment about "except for saving on an electric bill". An off-grid system is not going to save you money compared to being on the grid.

[robbyg]

Do you know who this solar guy on YouTube is? There are several solar Mining farms on there.

My thing is, I want to be completely self sufficient with a huge off grid solar system to power a window unit ac, fridge, computer, power tool charging, electric water heater etc.

Whatever power I have left over (should) go to profit, on an otherwise unprofitable solar system, except for saving on an electric bill. So why not use a solar system to generate additional income and help pay back an investment that I wanted anyway. If it doesn't all pan out, I still have a solar system.

Yes but he runs a competing forum so mentioning the name or place would probably not go over well.
In any case he only mentioned it briefly in one of his videos on another topic as he was panning the camera over his property and pointed out a bunch of panels that he is using for that setup. He then stated that he is thinking of giving it up and using the gear for something else. I don't think he would be giving it up if he had mined even a single coin.

[Fullblast]

There is another well known Solar Guy on YouTube who is trying the same thing and he has basically said he is giving up on it.
I get the feeling that your going to spend a whole lot more money on this system than what you will ever recoup from it.
And yes I know a single BT can generate 50K but I get the feeling from his post he has been running his a long time and had zero return.

Do you know who this solar guy on YouTube is? There are several solar Mining farms on there.

My thing is, I want to be completely self sufficient with a huge off grid solar system to power a window unit ac, fridge, computer, power tool charging, electric water heater etc.

Whatever power I have left over (should) go to profit, on an otherwise unprofitable solar system, except for saving on an electric bill. So why not use a solar system to generate additional income and help pay back an investment that I wanted anyway. If it doesn't all pan out, I still have a solar system.

[peakbagger]

The DC Solar reference is that the DC Solar trailers that got dumped on the market last year had large batteries (two 540 Amp Lead acids) , charge controllers and PV panels and in some cases diesel generators to equalize the batteries all assembled and in one piece for far below the selling cost of the components. Unbolt the arrays and convert to fixed mount, move the batteries, unbolt the electronics enclosure and sell the inverters and the trailer and your net cost is lot less than assembling from scratch. Go on YouTube and search for DC Solar and you will folks that are building large systems out of multiples of these trailers for the same reasons stated.