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Rate how I did on new shed install (w/ pics)

tvd1

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May 24, 2022
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So here is my completed install in my shed (still gotta clean up the wires a bit). 100w HQST panel on the shed (which is partially shaded). Harbor Freight 35ah battery (mem weekend sale, $50!), upgraded to the Renolgoy Rover MPPT 30a. 300w pure sine inverter, and a 30amp fuse between the battery and MPPT. Also a 15 amp fuse between the panel and MPPT (not visable). Definitely some tradeoffs but its a start.

So far i'm powering an LED strip light on the load side, and off the inverter is my moto battery tender running there. So far in the past few days the battery does struggle to fully charge and usually by the end of a sunny day the battery is at 60%. I'm going to add a motion sensor LED light to the front of the shed.. not sure if i can put it on the LOAD of the MPPT or i need to wire it into a plug on the inverter (Thoughts?).

Anyway, already looking like a second panel is likely going up in the near future, but that location would be even more shaded than the first one. So we'll see. Let me know what y'all think.
 

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Do you have a cut off device to disconnect PV panels to solar controller?
 
Ok, I do not know your controller but normally you you have to connect batteries first and then your PV when you have to do a shutdown. Not sure about your controller but it is a good idea to have a disconnect on your PV's incase you ever have to work on something.
 
The Renolgoy Rover MPPT 30a seems to be a fairly common controller. The instructions it came with were pretty good but make no mention of the switch. It did however make very clear to hook the batteries up first, which I did.

I only wonder if that Renology unit might be overkill for this application. My panel came with a cheap PWM controller, but others on this board made it seem like with my small battery that I would run into problems charging it effienciently.
 
The Renolgoy Rover MPPT 30a seems to be a fairly common controller. The instructions it came with were pretty good but make no mention of the switch. It did however make very clear to hook the batteries up first, which I did.

I only wonder if that Renology unit might be overkill for this application. My panel came with a cheap PWM controller, but others on this board made it seem like with my small battery that I would run into problems charging it effienciently.
That is my concern that if you need to take it down or service anything, you will have to disconnect wiring of the PV's each time instead of flipping a blade breaker to disconnect.

You made a good decision upgrading to the Rover MPPT instead of a PWM controller. It will grow with you in the future while you expand.
 
Im starting to get under voltage alerts on my MPPT. Im going to have to add a second solar panel. It just doesnt get charged enough and the inverter alone wears it down. Does anyone have any small (maybe 100w) inverters that are very resource light?
 
Thanks for that. How does one hook small inverters like that up to a battery? I know they just come with the car adapter.. I assume strip the wire and put grommets on it?
 
I believe that is just an Anderson connector and can ask them if that is the case.. otherwise yes, just cut the car adapter off if you want different end.
 
So the system is good now that i have two 100w panels (and a shut off switch, ty for the advice) but the battery is toast. Gets up to 100% charge during the day and like 30% at night. I know AGM's hate that cycle and its only a little 35ah guy. (which as i understand it equals 17ah in real life). So i'm looking to get a bigger AGM. Preferably 80ah to 125ah range.. But my requirements are affordable (obviously) and small (i dont have a ton of room). Any recommendations?
 
So the system is good now that i have two 100w panels (and a shut off switch, ty for the advice) but the battery is toast. Gets up to 100% charge during the day and like 30% at night. I know AGM's hate that cycle and its only a little 35ah guy. (which as i understand it equals 17ah in real life). So i'm looking to get a bigger AGM. Preferably 80ah to 125ah range.. But my requirements are affordable (obviously) and small (i dont have a ton of room). Any recommendations?
By your statement you need at least 20 percent more battery storage just to stay at 50 percent or actually "0"..
 
Indeed, 20-30% more would be ideal. And being in New England, this is the sunniest it will be here. So i'm going to guess i want to double that to 50-60% more when it gets cold and the sun gets lower.
 
Indeed, 20-30% more would be ideal. And being in New England, this is the sunniest it will be here. So i'm going to guess i want to double that to 50-60% more when it gets cold and the sun gets lower.
By the pic you have a 12 volt setup, correct? Getting a 100 AH battery is pretty standard. 100 AH translates to 1200 watts. So if you have 3 hours of direct sun per day you will need 400 watts of panel to charge the 100 AH battery just to get it back 100 percent each day. Now if you are also pulling power when the sun is shining you may not be getting the full 400 watts so you still may need to overpanel to make up the difference. What is your MPPT controller rated for as for watts and voltage?
 
I have a Renology 30amp MPPT ( https://renogy.com/rover-li-30-amp-mppt-solar-charge-controller/ ) .
Electrical Parameters
Nominal System Voltage12/24V (Auto-Detect for Non-Lithium types)
Rated Charge Current30A
Max. PV Input Voltage100 VDC
Max. PV Input Power12V/400W, 24V/800W
Power Consumption<100mA/12V; <58mA/24V
Max Battery Voltage32V
Ground TypeNegative

I have two 100w panels at the moment. I dont draw much current during the day, its usually the lights that pull the most (and used in the evening).
 
But my requirements are affordable (obviously) and small (i dont have a ton of room). Any recommendations?
Best bang for the buck in lead acid is the WallyWorld 120Ah DC29's you can usually get for $100 out the door. 60Ah usable, or about 4x what you've got now. About 200w of solar panels will get you about the 720Wh you can take out of that battery in 4 hours of sun. Over paneling is always helpful though. :)
 
I have a Renology 30amp MPPT ( https://renogy.com/rover-li-30-amp-mppt-solar-charge-controller/ ) .
Electrical Parameters
Nominal System Voltage12/24V (Auto-Detect for Non-Lithium types)
Rated Charge Current30A
Max. PV Input Voltage100 VDC
Max. PV Input Power12V/400W, 24V/800W
Power Consumption<100mA/12V; <58mA/24V
Max Battery Voltage32V
Ground TypeNegative

I have two 100w panels at the moment. I dont draw much current during the day, its usually the lights that pull the most (and used in the evening).
OK, so by your controllers specs you can put 400 watts of panels with a max VOC of 100 volts. Do you know your panel specs? In the future if you change your inverter to 24 volt system you could panel to your setup to 800 watts.
 
These are my panels:
1656514321480.png

For batteries, i've heard those Wally world batteries recommended before.

I've also been eyeing these 100ah batteries.. The only probablem with these (and the wally world) are the size. I can make them work, just not ideal.
Renogy Deep Cycle AGM Battery 12 Volt 100Ah ( https://www.amazon.com/Renogy-Battery-Marine-Off-grid-Applications/dp/B075RFXHYK?th=1 )
Weize 12V 100AH Deep Cycle AGM ( https://www.amazon.com/dp/B07SW353M8?tag=famoustool00-20&geniuslink=true&th=1 )
VMAX SLR100 12V 100ah ( https://www.amazon.com/dp/B01N4I6UZF/ref=emc_b_5_t )

VMAX also makes a smaller sized battery but its only 60ah
 
I question why you are using an inverter. Keep everything DC to conserve every watt you got.

DC LED lighting is easy to find. What voltage is your moto battery?
 
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