Powering up my shipping container

[SolarShedTed]

I don't want to shock myself or blow anything up so I'm here to get confirmarion on my equipment along with a little advice.

I'm powering a 20 foot shipping container with a 5000w 24v pure sine wave converter.
I plan to parallel six 350w panels on the roof (although I have room for 4 additional panels). The PV array will be connected to a OOYCYOO MPPT 100a charge controller to charge the battery bank. Between this charge controller and the 5000w inverter I plan to use a Tocas 100a circut breaker. Between the inverter and the battery bank I plan to use a Tocas 250a circut breaker.

The questions I have are:
Wire: Panels have 10awg, should I use 4awg to run from the connector branchs to the charge controller?
Batteries: I'm on a budget and need the cheapest batteries that will provide 5000w of power for 12 hours straight. There are three 1500 watt appliances that will need to run uninterrupted at night with this system being the only source of power.

Knowledge is a gift. I respect your time and advice. Thank you in advance for helping me live through this adventure.

 

[sunshine_eggo]

I don't want to shock myself or blow anything up so I'm here to get confirmarion on my equipment along with a little advice.

I'm powering a 20 foot shipping container with a 5000w 24v pure sine wave converter.

Assuming something cheap like the bottom-of-the-barrel MPPT?

I plan to parallel six 350w panels on the roof (although I have room for 4 additional panels).

Paralleling 24V panels on a 24V system fails to take full advantage of MPPT.

Each panel MUST have a fuse.

The PV array will be connected to a OOYCYOO MPPT 100a charge controller to charge the battery bank.

100Voc Limit? Sometimes, you shouldn't go with cheapest.

Between this charge controller and the 5000w inverter I plan to use a Tocas 100a circut breaker.

Over-current protection should be 1.25X max anticipated current, and it should be a high quality component priced similarly to BlueSea components.

Between the inverter and the battery bank I plan to use a Tocas 250a circut breaker.

5000/24/.85 * 1.25 = 306A

The questions I have are:
Wire: Panels have 10awg, should I use 4awg to run from the connector branchs to the charge controller?

Combined wire must be capable of handling 6X Isc, e.g., if the Isc of your panels is 9A, the cable must handle 54A.

Batteries: I'm on a budget and need the cheapest batteries that will provide 5000w of power for 12 hours straight. There are three 1500 watt appliances that will need to run uninterrupted at night with this system being the only source of power.

I hope you have a shit-ton of money. Those 5000W of loads for 12 hours is 2X the average U.S. household daily power consumption.

First 5000W * 12h = 60kWh. Your panels MIGHT produce 6 * 350W * 5 = 10kWh.

If you DIY your own LFP batteries, that should only cost about $10,000, and it can be used one out of every 6 days since your panels can only produce 1/6th of what you need.

 

[sunshine_eggo]

Are you going to be as interactive as you were here?

Powering a HUGE air compressor

I'm building out a 20 foot shipping container to act as a large sandblasting cabinet. I'd like to power a huge 3 phase 240v 29a 10hp air compressor with solar. What would be the bare necessities for such a solar draw? Any knowledge shared would be appreciated. Thank You

diysolarforum.com

 

[Hedges]

Over-current protection should be 1.25X max anticipated current, and it should be a high quality component priced similarly to BlueSea components.

1.25x for most loads (to avoid nuisance trips. 1.56x (= 1.25 x 1.25) of Isc for PV, because PV output can exceed Isc.
Wire ampacity at least that 1.25x or 1.56x, of course; must equal or exceed OCP.

 

[sunshine_eggo]

1.25x for most loads (to avoid nuisance trips. 1.56x (= 1.25 x 1.25) of Isc for PV, because PV output an exceed Isc.
Wire ampacity at least that 1.25x or 1.56x, of course; must equal or exceed OCP.

Thanks. You think he'll read it?

 

[SolarShedTed]

Assuming something cheap like the bottom-of-the-barrel MPPT?



Paralleling 24V panels on a 24V system fails to take full advantage of MPPT.

The panels are 12v. I will be running them in a series instead of parallel to get the 24v. Or would you recommend something different?

Each panel MUST have a fuse.

I will add these to the list.

100Voc Limit? Sometimes, you shouldn't go with cheapest.

Sounds like I'd need a larger charger control, or should I split the battery bank into two and use two charge controllers? Or more?

Over-current protection should be 1.25X max anticipated current, and it should be a high quality component priced similarly to BlueSea components.

So I suppose I need to figure out the charge control situation first then revisit this?

5000/24/.85 * 1.25 = 306A

I will upgrade accordingly

Combined wire must be capable of handling 6X Isc, e.g., if the Isc of your panels is 9A, the cable must handle 54A.

So 4awg would be overkill? 10awg should be fine?

I hope you have a shit-ton of money. Those 5000W of loads for 12 hours is 2X the average U.S. household daily power consumption.

First 5000W * 12h = 60kWh. Your panels MIGHT produce 6 * 350W * 5 = 10kWh.

I do have another 14 panels (20 total) and plenty if room for a ground mounted system.

If you DIY your own LFP batteries, that should only cost about $10,000, and it can be used one out of every 6 days since your panels can only produce 1/6th of what you need.

I need to go super cheap upfront cost. I have access to as many 12v sealed acid batteries that I need. So for me, that's the cheapest. Duralast 27DC Group 27 Deep Cycle Marine and RV Battery are the ones I have greatest access too. They are 12v 85ah. Would these even work or is this just getting more idiotic?

 

[SolarShedTed]

Are you going to be as interactive as you were here?

Powering a HUGE air compressor

I'm building out a 20 foot shipping container to act as a large sandblasting cabinet. I'd like to power a huge 3 phase 240v 29a 10hp air compressor with solar. What would be the bare necessities for such a solar draw? Any knowledge shared would be appreciated. Thank You

diysolarforum.com

Maybe. Depends on if my family all catches Covid again.

 

[SolarShedTed]

1.25x for most loads (to avoid nuisance trips. 1.56x (= 1.25 x 1.25) of Isc for PV, because PV output can exceed Isc.
Wire ampacity at least that 1.25x or 1.56x, of course; must equal or exceed OCP.

See... no one agrees and thus newbie confusion is inevitable.

 

[SolarShedTed]

Thanks. You think he'll read it?

I did. But did I understand it is the more appropriate question.

 

[sunshine_eggo]

The panels are 12v. I will be running them in a series instead of parallel to get the 24v. Or would you recommend something different?

I've never seen a 350W 12V panel. Please link.

Sounds like I'd need a larger charger control, or should I split the battery bank into two and use two charge controllers? Or more?

Better one(s).

So I suppose I need to figure out the charge control situation first then revisit this?

Yep.

So 4awg would be overkill? 10awg should be fine?

No. No.

I do have another 14 panels (20 total) and plenty if room for a ground mounted system.

Good.

20 * 350W * 5h/day = 35kWh - about half of what you need.

I need to go super cheap upfront cost. I have access to as many 12v sealed acid batteries that I need. So for me, that's the cheapest. Duralast 27DC Group 27 Deep Cycle Marine and RV Battery are the ones I have greatest access too. They are 12v 85ah. Would these even work or is this just getting more idiotic?

12 * 85Ah = 1020Wh, half of which is usable, 510W

60000/510 = You'll need 118 batteries to form a bank that will give every battery manufacturer on the planet a heart attack.

Even if you switched to 48V w/120 batteries, that's a 4S30P bank. The stuff nightmares of made of.

Maybe. Depends on if my family all catches Covid again.

Welcome back then! Hope everybody's fully recovered.

See... no one agrees and thus newbie confusion is inevitable.

Listen to him. He's smarter than I am.

I did. But did I understand it is the more appropriate question.

If you require clarification, please ask.

Summary:

You need 40 350W panels.
You should upgrade to 48V inverter that's capable of >5000W with a good surge rating as I assume you're still talking about your compressor.
At 48V, you'll need 40*350W/56V = 250A of MPPT chargers.
You'll need 120 12V 85Ah batteries in a 4S30P configuration with probably > $1000 of at least 2/00 interconnects.

 

[Hedges]

See... no one agrees and thus newbie confusion is inevitable.

I think we agree; I just refreshed his memory. Or educated him. I think 1.56x is in NEC.
Fuses/breakers should never trip except in case of a fault. Fuses in PV strings might never trip, except if 3 or more strings and one shorts. One or 2 strings, fuse rating is never exceeded, so it isn't needed (in most systems; tranformerless GT inverters I think do, on account of possible backfeed.)

Newbie has to sort through the details (inevitable confusion, as you say) or wait until the shouting stops.
I learn things here too.

Listen to him. He's smarter than I am.

Trust me, it took a while and I've paid the tuition.

 

[Checkthisout]

How far away is grid power?

You need grid power.

 

[Bud Martin]

I think OP should provide the full spec of the panels and the charge controller.

 

[50ShadesOfDirt]

Grid power not necessary, especially if not nearby and/or cost-prohibitive, or just desiring off-grid.

For such large continuous loads, I'd integrate a propane genny (w/ associated onsite 500gal propane tank); ensure genny has autostart capability. Utilize a 24v/48v inverter w/ auto-start module. Utilize LFP batteries w/ lots of cycles & DoD down to 90%. All of this nets an instant off-grid "power grid" that keeps batteries replenished as your loads draw them down; generator is not running continuously, but autostarted as needed by the smart inverter.

You become your own utility grid operator.

To this, add mppt & solar panels, to reduce genny runtime.

This is how we operate off-grid (Magnum 4024, LFP).

 

[Checkthisout]

Grid power not necessary, especially if not nearby and/or cost-prohibitive, or just desiring off-grid.

For such large continuous loads, I'd integrate a propane genny (w/ associated onsite 500gal propane tank); ensure genny has autostart capability. Utilize a 24v/48v inverter w/ auto-start module. Utilize LFP batteries w/ lots of cycles & DoD down to 90%. All of this nets an instant off-grid "power grid" that keeps batteries replenished as your loads draw them down; generator is not running continuously, but autostarted as needed by the smart inverter.

You become your own utility grid operator.

To this, add mppt & solar panels, to reduce genny runtime.

This is how we operate off-grid (Magnum 4024, LFP).

That's how everyone operates off grid.

 

[50ShadesOfDirt]

Someone above said OP needed "grid power" ... thought it worth repeating that off-grid w/ "inverter-charger/battery-bank/genny" is an option.

 

[Rednecktek]

The panels are 12v. I will be running them in a series instead of parallel to get the 24v. Or would you recommend something different?

Those are marketing terms, not real world numbers. What it means is that a "12v Panel" can produce enough voltage to charge a 12v battery, but not enough to do a 24v battery. Likewise a "48v Panel" will produce enough voltage to charge a 48v battery, or a 24v, or a 12v. When you're calculating for your SCC the only time those numbers really come into play is if you're using a cheapie PWM controller. Since the PWM controllers just clip voltage to whatever battery voltage is, going over that is a waste of energy.

For example, if you've got a little 12v panel on a 12v PWM controller and a 12v battery, the panel is probably producing 18-ish volts and the PWM is just clipping that down to the 13.5-ish that your battery uses. Anything between that 13.5 and 18 is just dumped/wasted. If you were to throw a 48v 300w panel on a 12v PWM and battery, that's anything between 13.5 and 60v that's just wasted and only 5 amps going into your battery (and probably fried your little controller in the process anyways! ). That's where the whole 12v/24v/48v panel thing really comes into play and your panel, PWM, and battery all need to be in the same range.

Now, let's say that your little PWM just wasn't able to handle those "48v" panels your friend gave you for your birthday and you went and picked yourself up a decent little MPPT controller. Now things start getting good! The MPPT controller is trying to do all its battery math by watts, so your fancy 48v 300w panel is pumping 60v into the controller. The controller knows it's a 12v battery, so it's going to take the extra voltage and convert it to amperage. Now that 5a @ 60v is coming into the MPPT and it's being converted to 25a @ 12v of charging going to the battery. That's a helluva improvement! Since the MPPT can actually USE the excess voltage you gain a LOT more efficiency out of it.

Add into that the amperage rating of the SCC. If a SCC can do 100a, then it's 100a at whatever voltage. So if you were running a 100a SCC on a 12v battery, you couldn't use more than 1200w of panel. Bump that battery bank to 24v and now you've doubled your usable panel wattage to 2400w AND cut your wire size down significantly. In your case, you should really look at a 48v system. Now your 100a SCC can use 4800w of panel AND your wire and fuse sized are dropped even further. A 5kw inverter on a 24v line is a 250a fuse and AWGHonkinHuge wire, but on a 48v setup is only 125a and AWGRealistic size wire.

Also, since you want to give yourself a little headroom on fuses, your 100a SCC should have a 125a fuse going out.

Wire up your panels in series as much as you can, get a better quality MPPT that can take a higher VoC input and you'll be a LOT better off.

Also, what kind of appliances need 1500w ea for 12 hours? You're not running electric heaters in there are you?!?! If you are, the general consensus for heating is "Anything But Electricity" because it beats the krap out of your battery banks.

 

[Bluedog225]

Do not put lead acid batteries of any type inside the container. Boom.

 

[Checkthisout]

Do not put lead acid batteries of any type inside the container. Boom.

Boom?

 

[Rednecktek]

Do not put lead acid batteries of any type inside the container. Boom.

In an enclosure with outside ventilation and preferably a brushless or mechanical fan they should be fine. As long as you can seal the box so all the gas goes outside and doesn't fill the container. A roof vent turbine up top would evacuate any gas as well as long as there's somewhere lower for fresh air to come in.

Boom?

Lead acid batteries, especially flooded, will put off hydrogen gas as a side effect of charging the batteries. Shipping containers are designed to be water tight. Fill a container with hydrogen gas and add any kind of electric spark, say from static, a short, or a cheap relay and it could ignite it all at once.

Boom!