diy solar

diy solar

Building my first off grid system

H

Hauls Assington

New Member
Joined
Jun 13, 2022
Messages
75
I am a total newb, and would like opinions.

My goal is to be able to run 2 freezers, and a few little led lights.

I found these batteries, cheapest ones thaat were 12v 200ah, I would love to know if they are any good:https://www.amazon.com/dp/B09HH179Y...uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl

My plan is 2 12v 200ah batteries in series.

Or one 24v 200ah. Seems like it might be cheaper to get 2 12v 200ah.

I was planning on getting some used San Tan panels
https://www.ebay.com/itm/264926640027?epid=4046906489&hash=item3daedbb79b:g:K8wAAOSwwVZfpHo2

I was planning to get 12 of these.

Now the questions.

What charge controller, and what inverter?

Recommended batteries?

I have watched some youtube reviews of the “ampere time” ones.

I am pretty handy with fabricating stuff, and have enough room in the backyard, plan to build an array back there.


Like I said I am very new to all this, if you guys can think of a better way to run 2 freezers and a few lights, I am all ears.

Thanks!!
 
You are putting the cart in front of the horse. You haven't mentioned what the power requirements of your appliances even is, meaning you don't know a watt from a What?

Go to the Resources section and download and fill in the Energy Audit spreadsheet and do 2, one for now and 1 for not to distant future.

Then read about how each component required works. Read in the resources section the difference between low frequency and high frequency inverters.

Then read the many other posts or threads where people have asked similar questions to yours, over and over and over and some very bright and patient folks have provided all the info that you need to buy what you need.
 
Hauls Assington said:
My goal is to be able to run 2 freezers, and a few little led lights.
Click to expand...
That's what you say now but once you get solarized you'll want more o_O
A good start would be to get a kill a watt meter to measure your appliance's power needs.
easy to use
https://www.amazon.com/P3-International-P4460-Electricity-Monitor/dp/B000RGF29Q/ref=sr_1_2?crid=2ACMB77A7EACO&keywords=kill+a+watt+ez&qid=1656277153&s=hi&sprefix=kill+a+watt,tools,105&sr=1-2&th=1

No one can say exactly what you need until you've established your power requirements.
 
E. Cho said:
You are putting the cart in front of the horse. You haven't mentioned what the power requirements of your appliances even is, meaning you don't know a watt from a What?

Go to the Resources section and download and fill in the Energy Audit spreadsheet and do 2, one for now and 1 for not to distant future.

Then read about how each component required works. Read in the resources section the difference between low frequency and high frequency inverters.

Then read the many other posts or threads where people have asked similar questions to yours, over and over and over and some very bright and patient folks have provided all the info that you need to buy what you need.
Click to expand...
My god man, you could have just answered some simple questions, but instead you took time out of you day to be a complete wanker.
 
wiseacre said:
That's what you say now but once you get solarized you'll want more o_O
A good start would be to get a kill a watt meter to measure your appliance's power needs.
easy to use
https://www.amazon.com/P3-International-P4460-Electricity-Monitor/dp/B000RGF29Q/ref=sr_1_2?crid=2ACMB77A7EACO&keywords=kill+a+watt+ez&qid=1656277153&s=hi&sprefix=kill+a+watt,tools,105&sr=1-2&th=1

No one can say exactly what you need until you've established your power requirements.
Click to expand...
It is 2 freezers, you tell me. Will 3800 watts of solar panels and 2 g’s of batteries run it or not? COME ON!!!!
 
Hauls Assington said:
It is 2 freezers, you tell me. Will 3800 watts of solar panels and 2 g’s of batteries run it or not? COME ON!!!!
Click to expand...
Freezer -
414115.jpg

or
Freezer -
80L-Home-Small-Single-Solid-Door-Mechanical-Chest-Freezer-with-Ce.webp


your going to need to specify the power requirements of the devices you want to run before you can answer your question.
 
You don't need to Kill a Watt if you can read ... the consumer energy label.
You don't need batteries if you store energy in ice cubes.
Well, maybe a flashlight battery to power an LED flashlight.

Hauls Assington said:
I am a total newb, and would like opinions.
Click to expand...

You didn't seem to like some that were (honestly) offered :^)


Hauls Assington said:
Like I said I am very new to all this, if you guys can think of a better way to run 2 freezers and a few lights, I am all ears.
Click to expand...

And so I gave clues.
To be more explicit, something like this (with "Secure Power" outlet connected) and some PV panels.
One guy's video showed an installation with this model of grid-tie inverter, and without the grid connected it ran a LARGE angle grinder direct from PV.


There are other brands of batteries-optional hybrid inverters, which could be the best way to go. When you want to use the system for more and buy batteries (which are the most expensive part of the system), you can add on.
 
Ok, I have proceeded to actually acquire some stuff. Batteries came in along with the charge controller and inverter. I drove out to Phoenix and got 14 SanTan used panels. I decided to do a 12 panel array on the roof. Going to go 3s4p with the panels.

Here are some pics of the rack I am doing. I got some 2” angle iron, 1/8” thick. I made one rack for 6 panels and I am working on the other one.B2712B6C-88F2-415D-979C-1E0DE204A705.jpeg41B32547-238A-41E0-BA65-A89170421D10.jpegAAB1C530-E059-4F94-93B3-A21C562A9379.jpeg064FFCE1-A55D-40D1-B2DD-1260F46F9614.jpeg
 
Hauls Assington said:
I am a total newb, and would like opinions.

My goal is to be able to run 2 freezers, and a few little led lights.

I found these batteries, cheapest ones thaat were 12v 200ah, I would love to know if they are any good:https://www.amazon.com/dp/B09HH179Y...uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl

My plan is 2 12v 200ah batteries in series.

Or one 24v 200ah. Seems like it might be cheaper to get 2 12v 200ah.

I was planning on getting some used San Tan panels
https://www.ebay.com/itm/264926640027?epid=4046906489&hash=item3daedbb79b:g:K8wAAOSwwVZfpHo2

I was planning to get 12 of these.

Now the questions.

What charge controller, and what inverter?

Recommended batteries?

I have watched some youtube reviews of the “ampere time” ones.

I am pretty handy with fabricating stuff, and have enough room in the backyard, plan to build an array back there.


Like I said I am very new to all this, if you guys can think of a better way to run 2 freezers and a few lights, I am all ears.

Thanks!!
Click to expand...

I would 100% recommend you to build your own battery with 3.2v LiFePo4 cells, ie 4 for 12v system, 8 for 24v system or 16 for 48v.

I would also recommend a 48v system, it’s just more efficient than lower v systems that requires thicker cables.

From Docan Tech at Alibaba, you can get 16 cells with 125 ah each for 50$ a piece. Add a JK BMS for 186$ and you got a top notch 6kwh battery for under 1,000 USD.

The Batteries you link to could be of much worse quality, since these prebuilt cells almost always have a poor BMS (sort of controller of the battery) and used cells. I was a total noob when I built my battery, and got it done really fast. Building the battery is just very easy.

As to the charge controller and inverter, it’s here you can save money — with risk of having to tinker a lot or can get a bit more expensive stuff that will work out of the box.

I your budget allows it, I would get a Victron MultiPlus II 48/3,000 for app. 1,400 USD and a Victron MPPT Solar Charge Controller (bunch of versions available depending on your panel array) for app 800 USD. The MPII also allows you to charge your batteries with a petroleum generator and a bunch of other stuff. Everything can easily be made remotely controllable and you can supervise it on your phone.

I am sure others can provide information about cheaper alternatives for the inverter/SCC — but I don’t think there are any reasons to buy a pre-built battery, that is more expensive and always worse quality — and potentially a lot worse quality — than one based on raw cells. It’s labeled as “DIY” often, but really, you can put it together in like an hour and then it’s done. Nothing can really go wrong if the gear is proper.
 
By no means an expert, but at minimum I would fuse the battery, SCC and the panels and include an SCC cutoff. Might take a look at one or two of Will's blueprints.
 
Messier11 said:
I would 100% recommend you to build your own battery with 3.2v LiFePo4 cells, ie 4 for 12v system, 8 for 24v system or 16 for 48v.

I would also recommend a 48v system, it’s just more efficient than lower v systems that requires thicker cables.

From Docan Tech at Alibaba, you can get 16 cells with 125 ah each for 50$ a piece. Add a JK BMS for 186$ and you got a top notch 6kwh battery for under 1,000 USD.

The Batteries you link to could be of much worse quality, since these prebuilt cells almost always have a poor BMS (sort of controller of the battery) and used cells. I was a total noob when I built my battery, and got it done really fast. Building the battery is just very easy.

As to the charge controller and inverter, it’s here you can save money — with risk of having to tinker a lot or can get a bit more expensive stuff that will work out of the box.

I your budget allows it, I would get a Victron MultiPlus II 48/3,000 for app. 1,400 USD and a Victron MPPT Solar Charge Controller (bunch of versions available depending on your panel array) for app 800 USD. The MPII also allows you to charge your batteries with a petroleum generator and a bunch of other stuff. Everything can easily be made remotely controllable and you can supervise it on your phone.

I am sure others can provide information about cheaper alternatives for the inverter/SCC — but I don’t think there are any reasons to buy a pre-built battery, that is more expensive and always worse quality — and potentially a lot worse quality — than one based on raw cells. It’s labeled as “DIY” often, but really, you can put it together in like an hour and then it’s done. Nothing can really go wrong if the gear is proper.
Click to expand...
I already got all the parts, I switched on the imverter and it works, battery is wired, showing 51.7 volts.
 
I am going to put fuses between the panels
Hauls Assington said:
Do
mtnman1 said:
By no means an expert, but at minimum I would fuse the battery, SCC and the panels and include an SCC cutoff. Might take a look at one or two of Will's blueprints.
Click to expand...
Click to expand...
and the scc, and a breaker/switch between the scc and the batteries.
mtnman1 said:
By no means an expert, but at minimum I would fuse the battery, SCC and the panels and include an SCC cutoff. Might take a look at one or two of Will's blueprints.
Click to expand...
that is the plan, fuses between the panels and scc, I guess a switch too, then a breaker between the scc and the batteries. I meant do you have a link to wills diagram?
 
See the link at the top that says "DIY Solar blueprints" and it will take you to several different sized systems with a lot of good info. Will also has some good links to parts that he's used and can save you some wasted effort.

My current systems are a bit distinct from what you're putting together. I have a good bit of diff. equip. and DIY batteries, but looks like you're on the right track for a good start.
 
One other note, I can't tell what gauge your battery cables are, but the primary cables look a bit small. You may want to review the sizing and ensure that you have enough cable to support your battery/inverter
 
mtnman1 said:
One other note, I can't tell what gauge your battery cables are, but the primary cables look a bit small. You may want to review the sizing and ensure that you have enough cable to support your battery/inverter
Click to expand...
They are 3 awg thhn. Hopefully that will do her.
 
You must log in or register to reply here.

diy solar

diy solar
Back
Top