diy solar

diy solar

I'm a MAJOR neewbee

Newbeee

New Member
Joined
Jul 18, 2021
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11
Location
N, Arizona.
VERY bad idea posting the email address publicly
I feel like such a newbie that I'm going to just ask for help from Will or one of you other solar geniuses!! To finish this project.. I seem to just get more and more confused the more I study it. I'm older thank I thought! LOL. I have started to obtain parts for my SHF off grid system. I have bought now,,
1 ea victron MPPT 100V 50 A 12/24 v charge controller. 1 ea Victron Energy BMV smart monitor. 1 ea Gandel 4000 watt heavy duty pure sign wave inverter. 18 Siemens SR100 watt solar panels. They all match and were just pulled from a guys system that got upgraded so all were in use until then. I'm having trouble pulling the trigger on Battery's. I'm thinking of one of these 2 options but cant seem to keep it straight in my old head and having trouble pulling the trigger. Ether 4 ea signature solar EG4-Lifepower4 Lithium battery 24V 200 ah at about 6K OR 4 or 6 ea. EnjoyBot 12 V 300 ah Lifepo4 deep cycle at about 4k and 6 k respectively. I think both will work, not sure if all is compatible. Just not sure enough to pull the trigger. My daily use could be as big as 5208 wh? 12v think? I would like to keep going on this but cant afford a big $ mistake at this point. Please let me know what you think and a direction that will fill my goal and use the parts I've bought already. As I said its off grid, SHF system, built then to store un used (after its built I'm likely going to dissemble it and store in my basement for use in my basement, just in case its needed!) I realize I will need to run cords and or wire, and I can load shed my frigs with timers to prevent running at the same time. and I have that also. HELP! Thanks for any help!!

 
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It will be helpful if you can nail down your power needs more precisely. Also the general area where you live since that makes a big difference. My initial thought is that 1800 watts might not be enough for what you want to do. Guessing at power consumption is likely to leave you disappointed.
 
Well, I'll start the default answer to these questions and we can work from there. Here's you To-Do list:

1: Power audit! This will give you some important information on how big your inverter needs to be as well as how much battery capacity you'll need. There is a link in the FAQ section (I think, or someone here will post it shortly) so fill in the blanks and see what it comes up with. You'll probably need some sort of Kill-A-Watt to get accurate measurements. Are you going to be running a 12v system? 24v system? 48v system? What are the specs on your solar panels? VoC? Vmp? Being as this is a new build, throw together a wish list of what you want and estimate on the high side.

1a: Where do you live? Speccing out a system for Scotland is a LOT different numbers than Arizona due to the amount of light you actually get. Someone here can post the link to the PVwatts.com or JCR Solar Uber-Sun-Hours calculator sites to help figure out how much you'll have to work with. That will be a box in the Power Audit form.

2: Parts list: You don't need a make & model list, just a parts list to start from for reference. You'll need an inverter, a MPPT charge controller, fuses, shunt, buck converter, batteries, wire, etc. Once you have a basic list it can be fine tuned to make & models after that. If you're looking at the All-In-Ones check for correct voltage outputs (120v or 240v Split Phase for North America, 220v Single Phase for European type areas) and make sure it has enough capacity for a little bit of growth and fudge factor.

3: Budget!: Steak is great but doesn't mean anything if your wallet says hamburger. :) Figure out what you're able to spend now vs what you'll have to cheap out on now and upgrade later.

4: Tape measure! Figure out where you're going to stick all the stuff you'll need. A dozen 3000AH batteries sounds great until you're sleeping on the floor because there's no room left for a bed. Is there a compartment that can house all this stuff? Will the server rack batteries fit? Are you going to have to make space? Physics can be pretty unforgiving.

5: Pencil out what you think you need and throw it at us so we can tell you what you've missed (because we ALL miss stuff the first go-round :) ) and help figure out which parts and pieces you're going to want to get.
 
If you're planning for a SHTF scenario, you're going to either have to build some sort of faraday cage for the batteries (and everything else) or run on the assumption you'll be sticking with Lead Acids of some sort and factor in the 50% DoD for those in your calculations.
 
I feel like such a newbie that I'm going to just ask for help from Will or one of you other solar geniuses!! To finish this project.. I seem to just get more and more confused the more I study it. I'm older thank I thought! LOL. I have started to obtain parts for my SHF off grid system. I have bought now,,
1 ea victron MPPT 100V 50 A 12/24 v charge controller. 1 ea Victron Energy BMV smart monitor. 1 ea Gandel 4000 watt heavy duty pure sign wave inverter. 18 Siemens SR100 watt solar panels. They all match and were just pulled from a guys system that got upgraded so all were in use until then. I'm having trouble pulling the trigger on Battery's. I'm thinking of one of these 2 options but cant seem to keep it straight in my old head and having trouble pulling the trigger. Ether 4 ea signature solar EG4-Lifepower4 Lithium battery 24V 200 ah at about 6K OR 4 or 6 ea. EnjoyBot 12 V 300 ah Lifepo4 deep cycle at about 4k and 6 k respectively. I think both will work, not sure if all is compatible. Just not sure enough to pull the trigger. My daily use could be as big as 5208 wh? 12v think? I would like to keep going on this but cant afford a big $ mistake at this point. Please let me know what you think and a direction that will fill my goal and use the parts I've bought already. As I said its off grid, SHF system, built then to store un used (after its built I'm likely going to dissemble it and store in my basement for use in my basement, just in case its needed!) I realize I will need to run cords and or wire, and I can load shed my frigs with timers to prevent running at the same time. and I have that also. HELP! My e mail is loopdloop@pm.me in case its needed Thanks for any help!!

Here's one way to consider it, if you go with 6 enjoybot you'll get slightly more power storage (~21kWh vs ~19kWh).

I'm surprised youre going with a giandel inverter for such a large system. If you dont want to spend the money on a victron inverter, maybe consider samlex brand. they make a great 24V 4000W inverter (EVO4024). I strongly encourage you to rethink the decision. As the heart of your system, that's the last place you want to skimp on.

Furthermore, with a 4000W inverter, you really need to go with a 24V system or higher. Can the enjoybot batteries be connected in series for 24V?
 
I feel like such a newbie that I'm going to just ask for help from Will or one of you other solar geniuses!! To finish this project.. I seem to just get more and more confused the more I study it. I'm older thank I thought! LOL. I have started to obtain parts for my SHF off grid system. I have bought now,,
1 ea victron MPPT 100V 50 A 12/24 v charge controller. 1 ea Victron Energy BMV smart monitor. 1 ea Gandel 4000 watt heavy duty pure sign wave inverter. 18 Siemens SR100 watt solar panels. They all match and were just pulled from a guys system that got upgraded so all were in use until then. I'm having trouble pulling the trigger on Battery's. I'm thinking of one of these 2 options but cant seem to keep it straight in my old head and having trouble pulling the trigger. Ether 4 ea signature solar EG4-Lifepower4 Lithium battery 24V 200 ah at about 6K OR 4 or 6 ea. EnjoyBot 12 V 300 ah Lifepo4 deep cycle at about 4k and 6 k respectively. I think both will work, not sure if all is compatible. Just not sure enough to pull the trigger. My daily use could be as big as 5208 wh? 12v think? I would like to keep going on this but cant afford a big $ mistake at this point. Please let me know what you think and a direction that will fill my goal and use the parts I've bought already. As I said its off grid, SHF system, built then to store un used (after its built I'm likely going to dissemble it and store in my basement for use in my basement, just in case its needed!) I realize I will need to run cords and or wire, and I can load shed my frigs with timers to prevent running at the same time. and I have that also. HELP! My e mail is loopdloop@pm.me in case its needed Thanks for any help!!

Join the club newby :)
if you put your teeth in it you'll get to leave our club :)
 
Bobert
It will be helpful if you can nail down your power needs more precisely. Also the general area where you live since that makes a big difference. My initial thought is that 1800 watts might not be enough for what you want to do. Guessing at power consumption is likely to leave you disappoi

It will be helpful if you can nail down your power needs more precisely. Also the general area where you live since that makes a big difference. My initial thought is that 1800 watts might not be enough for what you want to do. Guessing at power consumption is likely to leave you disappointed.
Thanks Bobert I hope that means the rest of the system might work as planed.
Yes Im in N Az. The 5.32 hrs of sun per day but roof is facing due east. Full morning sun. Little afternoon sun . Have room in this config for 16 panels. My 100 w panels are used but good. I don't know if I can combine a few more newer panels with some combiner box or something to raise the watts in and still use my old panels? My daily power usage is 5516 WH but that is in 12v. as the calculator is for a 12 v camper system. This daily use is likely a little high as I will be load shedding . Ie not running freezers all at once etc.
Does any of this help?
 
It looks to me that you don’t have enough solar to be safe. If you have just barely enough to run your load under ideal conditions. You probably need double that unless you have a backup plan to recharge on bad days or in the event of equipment failure. If it was me and I really wanted to use solar (and I would) I would take what I have, add an eg4 battery have a generator or grid power on hand just in case. Exactly what else I need would become very obvious.
It would be different if I was starting from scratch
 
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