diy solar

diy solar

few questions about solar power....

if you believe 48 volts is better than more storage capacity, so be it.. will i be able to use the same 3 solar panels that i insanely walked onto my roof next to my window ? 2 are 350watts and one is 400 or 450 watts... all 3 are physically different sizes......

sooo.. i need 4x 12volt batteries ? 4 fuses ?(how many amps?)... cable to link battery to battery... (what gauge would you recommend ?).. and an inverter that will be 48v dc to ac ??? charge controllers? or should i just forget that ??

as for aio.. there are som AIO systems using LFE batteries at ludacris prices and proprietary solar connectors....... tbh, im actually better off buying an ecoflow with solar panel included, but being a cheap french Canadian bastard, i thought id save cash by putting the whole system together myself.. but i really dont need to use 300 watts during the nighttime.. ill just use land power.... by the way if the solar panels only produce 18v at peak, how do i connect them to a 48volt system ?

thank you...
 
if you believe 48 volts is better than more storage capacity, so be it.. will i be able to use the same 3 solar panels that i insanely walked onto my roof next to my window ? 2 are 350watts and one is 400 or 450 watts... all 3 are physically different sizes......
48v can have the same capacity.. There isn't just some magical "more storage capacity"
4 batteries at 12 volts and 100 amp hours = 400 amp hours = 4800 watt hours
1 battery at 48 volts and 100 amp hours = 4800 watt hours
1 48 volt battery = 4x 12 volt batteries

All 3 of solar panels should be rated the same or they will run at the worst panel's specs, but yea you can still use it
You only need 1 fuse if you have 1 48v battery and all of them in series

I don't even know what's available there, what your panels real specs are, what batteries you have available (seems only lead acid?) etc so it's difficult to help
 
48v can have the same capacity.. There isn't just some magical "more storage capacity"
4 batteries at 12 volts and 100 amp hours = 400 amp hours = 4800 watt hours
1 battery at 48 volts and 100 amp hours = 4800 watt hours
1 48 volt battery = 4x 12 volt batteries

All 3 of solar panels should be rated the same or they will run at the worst panel's specs, but yea you can still use it
You only need 1 fuse if you have 1 48v battery and all of them in series

I don't even know what's available there, what your panels real specs are, what batteries you have available (seems only lead acid?) etc so it's difficult to help
thank you for your input but do i REALLY need 4 batteries (yes SLA) to use a computer and monitor and lets throw in a fiber optics modem for tits and giggles.... im no expert or electrician but wouldnt connecting 3 solar panels that only produce 18volts to a 48volt system be counter productive ??

okay.. i will TRY to list what i have thus far
12V 100AH JSLII-TF100-12 battery
solar panel..350watts
solar panel 350watts
solar panel 400-450watts
chinese modified sine wave inverter 12V 700 watts... no brand, covered in mandarin
chinese (chernobyl looking device) power sonici 12v dc to 300watt ac inverter....model s-300
very chinese and very cheap charge controller with no branding....
the first inverter no longer has clamps and absolutely refuses to come on(and i put ring terminals to connect to the battery posts.. terminals, watever)
the second inverter flashes a light when the second clamp (battery contact ??) touches the second terminal.. even with the switch set to off.. when i press the power... switch.. it bounces from off to on every minute...
oh.. lets throw this in for fun.. possibly brass ? ring terminals....
 
I've asked for the actual solar panel spces like 4 times now so I'm just gonna leave this here.
take a pic of the back of them or something.
You keep saying only 18 volts but then you say 400 watts, that's a 22 amp solar panel I never see any weird ones like that
 
I've asked for the actual solar panel spces like 4 times now so I'm just gonna leave this here.
take a pic of the back of them or something.
You keep saying only 18 volts but then you say 400 watts, that's a 22 amp solar panel I never see any weird ones like that
there is no brand name whatsoever on all 3 solar panels...... if you scroll up you can seea video linked onto the rumble website... and you can see a video of my tiny system...... if i will need a battery replacement.. should i upgrade to lfe ?.. ive seen a 3.2V battery for a nice price.. i figure if i series link 4 that technically gives me 12 or so volts... and a touch more than 100ah...its a big rectangular one not the umm 18680 cylinder one.....
 
Yea the panel ratings are what matter to know what you're getting from them. Otherwise it is impossible to guess.
 
My 2 cents and worth that...

What is your end state goal? Are you looking to power a house, a shack, a tent? How long?

You stated the AC and your laptop...if you want to do a little more the answer will be different than if you want to eventually do a whole house.

This is in terms of buying equipment that can be used in the end state system.

Next after the energy audit pick a battery voltage. Pick the highest that makes sense that you can do. For small end state I would pick 24v if you can't manage 48v.

For the battery voltage you can make it up by stacking batteries in series but that introduces problem with equalizing voltages so they charge and discharge evenly. If they are uneven you will have to disconnect them periodically and charge separately. That or you will need an active or passive balancer depending on your battery chemistry.

BUT, The best possible thing you can do is buy a single battery of the right voltage. And it is well worth the trouble and expense to get a LiFePO4. They are available in the Philippines, others on here have obtained them living a long way outside of Manilla and other cities. Might be worth taking another stab at it if you can swing it at all. 24v and the largest you can swing is a place to start.

All other components revolve around the battery voltage and capacity. How fast you can charge and how much you can pull out of it.

A FLA motorcycle battery is inadequate for pretty much anything but a led light. Typically that will be under 20ah. If it is standard the you can only use 30%. Which means about 72watt hours. So 72 watts for 1 hour. Your laptop may draw more than this. A motorcycle battery maxes out at about 3amps for charge.


The system I built for a UPS for my CPAP in case power goes out is '12v100ah mini 'and has 1280wh in it, 1000 of those are usable. It will power my CPAP for about 30 hours, or 3 nights. This is running a dc-dc converter from the battery verse an inverter. The battery is 19lbs and about twice the size as a motorcycle battery. It can take a charge current of up to 100amps but recommended is 20amps for longevity. But it can be safely charged to 50amps without damage.

The 12v100ah is the same capacity and size as a 24v50ah. The major difference the size of the wires, fuses, inverter, and mppt. The savings for all of these may make up the extra battery cost. It will be more efficient than a 12v as well. With a LiFePO4 battery you will be able to capture more of the sunlight just because you can charge at the higher rate.

I lived in Guam and in the PI in my Navy days (35 years ago) so I get that some things are hard to come by. But, some things are worth the extra time and cost.
 
raining at the moment, any chance i can get an answer about the 4x 3.2v lithium rectangle batteries ?i want to connect 4 of them in series and use that as a solar power bank...

as for the dead 12v battery i have next to me, ive read that if you pour out the battery acid and poor in a distilled water and epsom salt solution and slow charge it.. it might repair the cathode and anodes inside the battery.. it is a cheap solution to repair it.. that.. or purchase 4x 3.2v lithium batteries and link them....
 
My 2 cents and worth that...

What is your end state goal? Are you looking to power a house, a shack, a tent? How long?

You stated the AC and your laptop...if you want to do a little more the answer will be different than if you want to eventually do a whole house.

This is in terms of buying equipment that can be used in the end state system.

Next after the energy audit pick a battery voltage. Pick the highest that makes sense that you can do. For small end state I would pick 24v if you can't manage 48v.

For the battery voltage you can make it up by stacking batteries in series but that introduces problem with equalizing voltages so they charge and discharge evenly. If they are uneven you will have to disconnect them periodically and charge separately. That or you will need an active or passive balancer depending on your battery chemistry.

BUT, The best possible thing you can do is buy a single battery of the right voltage. And it is well worth the trouble and expense to get a LiFePO4. They are available in the Philippines, others on here have obtained them living a long way outside of Manilla and other cities. Might be worth taking another stab at it if you can swing it at all. 24v and the largest you can swing is a place to start.

All other components revolve around the battery voltage and capacity. How fast you can charge and how much you can pull out of it.

A FLA motorcycle battery is inadequate for pretty much anything but a led light. Typically that will be under 20ah. If it is standard the you can only use 30%. Which means about 72watt hours. So 72 watts for 1 hour. Your laptop may draw more than this. A motorcycle battery maxes out at about 3amps for charge.


The system I built for a UPS for my CPAP in case power goes out is '12v100ah mini 'and has 1280wh in it, 1000 of those are usable. It will power my CPAP for about 30 hours, or 3 nights. This is running a dc-dc converter from the battery verse an inverter. The battery is 19lbs and about twice the size as a motorcycle battery. It can take a charge current of up to 100amps but recommended is 20amps for longevity. But it can be safely charged to 50amps without damage.

The 12v100ah is the same capacity and size as a 24v50ah. The major difference the size of the wires, fuses, inverter, and mppt. The savings for all of these may make up the extra battery cost. It will be more efficient than a 12v as well. With a LiFePO4 battery you will be able to capture more of the sunlight just because you can charge at the higher rate.

I lived in Guam and in the PI in my Navy days (35 years ago) so I get that some things are hard to come by. But, some things are worth the extra time and cost.
cool Guam.. i think that is or used to be a us territory....i think i dont quite understand sunlight power, i kind of figured the battery will capture any watts you connect to it as long as its roughly the same voltage....so i got 3 solar panels separately....... and my CPAP is in the hands of my mother back in Quebec, i would ask her to ship it to me but i dont know if it is 220v compatible....also since my healthcare doesnt quite reach here, i would have to PAY for distilled water.... and i dont quite know how much distilled water a very new CPAP uses.... please understand that Canada, especially Quebec is socialist.. so.. capitalism is difficult to dive into....


oh sorry.. iWANTED to use the solar for everything.. but.. for now.. i just want to power my computer tower and monitor and possibly a small refridgerator... (48L).. simply during the daytime and plug all 3 of those into land power during the nighttime....which is why i asked if i can use a motorcycle battery... because i dont care about storage at this point.. i just want to access my solar panels power period....
i figured if i just use the inverter during sunlight hours.. the power would just jump into the battery and then dive into the inverter... honestly ifcan tap into the solar panels without using a power bank... i would.. my pc has a ups and the fridge should be accustomed to power outages

PS: just looked and apperantly my fridge is rated at 53Watts... i dont think that is very much but.. now you know :)
 
Assuming your cpap is resmed it is world wide, just needs to physically plug in. With heated hose and humidifier tank it draws 2 to 7 amps from the dc-dc converter from 12v. Turn off the heat and just run plain and it is only an amp or so at 12v. If running off the inverter the power cube draws an amp or less. So, between 90watt hours and 300watt hours depending on how long you sleep and how it is connected and configured.

For water - if you can drink it you can use it. If other than distilled just empty the tank every morning and let sit open to dry. Then fill at night before use. And realize you may need to let the tank sit wit vinegar and water in it once a week to get any deposits out of it.

You loose the inverter efficiency if you run from ac but you want to avoid running directly from battery if you have a panel or charger connected. The resmed dc-dc converter regulates the voltage and is a boost/buck so it will raiseor lower to exactly 24v as long as you have input between 11v and 29v. All resmed cpap are 24vdc.

If your cpap is another brand have mom check if it is a power brick like a laptop uses and send a picture of back of it. Chances are it is 110-240 50-60hz which means just a physical adapter.

Whatever you do, have her send sparesfor everything you can.
 
wen

went onto the roof and took a video underneath all 3 large solar panels.. uploading now...
1 no lable or sticker
2nd.. 300w
3rd 400w
what are their open circuit voltage etc?..
I can't actually recommend anything if I don't know anything with what you have
 
Assuming your cpap is resmed it is world wide, just needs to physically plug in. With heated hose and humidifier tank it draws 2 to 7 amps from the dc-dc converter from 12v. Turn off the heat and just run plain and it is only an amp or so at 12v. If running off the inverter the power cube draws an amp or less. So, between 90watt hours and 300watt hours depending on how long you sleep and how it is connected and configured.

For water - if you can drink it you can use it. If other than distilled just empty the tank every morning and let sit open to dry. Then fill at night before use. And realize you may need to let the tank sit wit vinegar and water in it once a week to get any deposits out of it.

You loose the inverter efficiency if you run from ac but you want to avoid running directly from battery if you have a panel or charger connected. The resmed dc-dc converter regulates the voltage and is a boost/buck so it will raiseor lower to exactly 24v as long as you have input between 11v and 29v. All resmed cpap are 24vdc.

If your cpap is another brand have mom check if it is a power brick like a laptop uses and send a picture of back of it. Chances are it is 110-240 50-60hz which means just a physical adapter.

Whatever you do, have her send sparesfor everything you can.
will do thank you, i dont remember much about the actual cpap (ie, brand etc) except that the price tag was 1700$cad and i didnt lose a penny out of my pocket to get it... not that Canada has pennies anymore but regardless...
 
what are their open circuit voltage etc?..
I can't actually recommend anything if I don't know anything with what you have
on the 3rd solar panel it did list 18volts.... that is about it im afraid... let me check if the video of my insane walk on the roof has completed uploading and processing...
and VOILA... here you go, please forgive the shaking but i was 3-4m from a painful landing...

 
on the 3rd solar panel it did list 18volts.... that is about it im afraid... let me check if the video of my insane walk on the roof has completed uploading and processing...
and VOILA... here you go, please forgive the shaking but i was 3-4m from a painful landing...

1711688407738.png

omg man you could have taken this picture days ago
those panels are tiny as hell. How do they make 400 watts? are they like 80% efficient? breaking every record in the game


what stores can you buy from there? aliexpress? There are charge controllers that can handle your panels in series
There are charge controllers that can handle all of your stuff
but like I said, your worst panel will be where all of them run at. In series it'll be the worst voltage

The benefit of that one is it'll send the solar or the battery output to it's output to your inverter and instead of pulling only from batteries you can pull from solar/battery at same time from your inverter

That's why people like the AIO ones but idk what you can even buy where you are
 
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Looking at the physical size of those panels, there is no way they are really 300 and 400 watts.

They look even smaller than my 100 watt panels that are rated at 22% efficient. And yes, size does matter on solar panels. Sunlight at noon with a clear sky puts roughly 1,000 watts of energy per square meter of surface it hits. So a panel that is 1 square meter and 25% efficient would output 250 watts. My 100 watt panels are just over 700 mm x 700 mm or about 0.49 square meters. call it .5 or 500 watts of sun x 0.22 (22% efficient) and we get 110 watts. There is a little space between the cells and the frame etc. so the 100 watt rating works out. Here is a picture of my array of the 100 watt panels.

IMG_2878.jpg IMG_2877.jpg

That is 10 of them together to make a 1,000 watt array. The total array is about 1.5 meters x 3.6 meters. They are wired 5 in series, then the two rows are in parallel. Each panel is 18 volts at 5.5 amps, the whole array is then 90 volts at 11 amps. 90 x 11 = 990 watts. The VOC is 22 volts so x 5 in series is 110 volts. The other row of panels you can see in the left picture is another row of 5 x 200 watt panels making another 1,000 watts.

As for using 4 x 3.2 volt LFP cells, yes that will make a solid 12 volt battery. But make sure to also add a proper BMS "Battery Management System". That is what will monitor the cells and keep it safe. Without a BMS, it does not take much to damage the cells and brick them like your lead acid battery. If something goes wrong and the solar panels try to over charge the battery, the BMS will shut it down and save the cells. If you use too much power and run the cells too low, the BMS will again shut off your load before the cells are dragged too low and damaged. If the system is working properly, the BMS does not do a whole lot, but it must be there. The better BMS units can have BlueTooth and you can monitor the battery with a cell phone app. Here is a screen shot of my 14S Li NMC battery BMS.

IMG_4799.PNG

14 cells in series is a typical 48 volt system with NMC cells as they are 3.7 volts nominal. LFP cells run a bit lower at 3.2 volts and you need 16 cells for 48 volts. 4 cells of LFP does 12 volts very well. My NMC cells don't hit 12 volts as 3 is too low and 4 is too high. My JK-BMS unit will take up to 24 cells, but only goes down to about 10 cells. They have different models that do work down at 4 cells.
 
Looking at the physical size of those panels, there is no way they are really 300 and 400 watts.

They look even smaller than my 100 watt panels that are rated at 22% efficient. And yes, size does matter on solar panels. Sunlight at noon with a clear sky puts roughly 1,000 watts of energy per square meter of surface it hits. So a panel that is 1 square meter and 25% efficient would output 250 watts. My 100 watt panels are just over 700 mm x 700 mm or about 0.49 square meters. call it .5 or 500 watts of sun x 0.22 (22% efficient) and we get 110 watts. There is a little space between the cells and the frame etc. so the 100 watt rating works out. Here is a picture of my array of the 100 watt panels.

View attachment 205477 View attachment 205478

That is 10 of them together to make a 1,000 watt array. The total array is about 1.5 meters x 3.6 meters. They are wired 5 in series, then the two rows are in parallel. Each panel is 18 volts at 5.5 amps, the whole array is then 90 volts at 11 amps. 90 x 11 = 990 watts. The VOC is 22 volts so x 5 in series is 110 volts. The other row of panels you can see in the left picture is another row of 5 x 200 watt panels making another 1,000 watts.

As for using 4 x 3.2 volt LFP cells, yes that will make a solid 12 volt battery. But make sure to also add a proper BMS "Battery Management System". That is what will monitor the cells and keep it safe. Without a BMS, it does not take much to damage the cells and brick them like your lead acid battery. If something goes wrong and the solar panels try to over charge the battery, the BMS will shut it down and save the cells. If you use too much power and run the cells too low, the BMS will again shut off your load before the cells are dragged too low and damaged. If the system is working properly, the BMS does not do a whole lot, but it must be there. The better BMS units can have BlueTooth and you can monitor the battery with a cell phone app. Here is a screen shot of my 14S Li NMC battery BMS.

View attachment 205476

14 cells in series is a typical 48 volt system with NMC cells as they are 3.7 volts nominal. LFP cells run a bit lower at 3.2 volts and you need 16 cells for 48 volts. 4 cells of LFP does 12 volts very well. My NMC cells don't hit 12 volts as 3 is too low and 4 is too high. My JK-BMS unit will take up to 24 cells, but only goes down to about 10 cells. They have different models that do work down at 4 cells.
PLEASE READ...

okay, need bms.. check.. but do i really need to buy 4 batteries and bms and cables and fuses ? just to run a pc and lcd monitor (and possibly a tiny fridge) during daylight hours ???

did nobody read the part i mentioned about trying to bring back THIS battery i have back to life ???using epsom salts/distilled water and a trickle charge.. i imagine that will be a hell of alot cheaper than 4x 3000 peso batteries ...and bms, wtv that is...and other things, why cant i just repair the infastructure that i already have here ?... OR... the other thing i mentioned twice... link 4x 3.2volt lithium batteries in series.. that there has slightly more capacity than a 100ah battery.. and apperantly is alot safer... just to make 1 x12v battery...


or why cant i just get a 12 to 24volt inverter.. if my battery voltage sits in between... wont it turn on anyways ? i just want power to flow from the solar panels to the 12v power bank to ups battery.. and from there it should harmlessly power a pc a monitor and who knows, maybe a tiny fridge ?
 
View attachment 205458

omg man you could have taken this picture days ago
those panels are tiny as hell. How do they make 400 watts? are they like 80% efficient? breaking every record in the game


what stores can you buy from there? aliexpress? There are charge controllers that can handle your panels in series
There are charge controllers that can handle all of your stuff
but like I said, your worst panel will be where all of them run at. In series it'll be the worst voltage

The benefit of that one is it'll send the solar or the battery output to it's output to your inverter and instead of pulling only from batteries you can pull from solar/battery at same time from your inverter

That's why people like the AIO ones but idk what you can even buy where you are
yeah.. and this will tickle your brain too.. each solar panel only cost me 30$cad.... .. but only 1 actually came with a charge controller...

yes, im aware that these solar panels arent huge, but im alot closer to China than you are at the moment (i think).. so Philipines has slightly quicker access to the new developements coming out of china than north america...
yes i have access to alibaba...but they really rip you off in terms of shipment.. if some of the sellers on tiktok shop are from china.. (it happens). then shipping is more reasonable... i also have access to made-in-china app
shoppee
lazada
shein
tiktok shop



the last 4 are the most reasonable of all in terms of shipping costs...
 
PLEASE READ...

okay, need bms.. check.. but do i really need to buy 4 batteries and bms and cables and fuses ? just to run a pc and lcd monitor (and possibly a tiny fridge) during daylight hours ???

did nobody read the part i mentioned about trying to bring back THIS battery i have back to life ???using epsom salts/distilled water and a trickle charge.. i imagine that will be a hell of alot cheaper than 4x 3000 peso batteries ...and bms, wtv that is...and other things, why cant i just repair the infastructure that i already have here ?... OR... the other thing i mentioned twice... link 4x 3.2volt lithium batteries in series.. that there has slightly more capacity than a 100ah battery.. and apperantly is alot safer... just to make 1 x12v battery...


or why cant i just get a 12 to 24volt inverter.. if my battery voltage sits in between... wont it turn on anyways ? i just want power to flow from the solar panels to the 12v power bank to ups battery.. and from there it should harmlessly power a pc a monitor and who knows, maybe a tiny fridge ?


Once a battery is toast it is toast - the plates have spikes sticking out from them into the next plate shorting at least one cell and probably more. No amount of salt, water, acid, or any other thing will bring it back to life or or to its regular capacity. I know you want to try all the "tricks" on the internet to revive it but those aren't going to give you battery you can push current in and out of they might give you voltage that works for a short time but no real current out of it.
That is a problem with lead acid batteries -


The battery you list is 12V 100AH JSLII-TF100-12 battery -- this shows as a sealed lead acid (SLA) battery - that means it has a 1-way vent in it to let it off-gass when you over discharge it or over charge it. Max recommeneded DOD on this is 50% which means 50ah. 12 x 50 = 600wh. String 4 together and you will get 1200wh. The other thing about sealed lead acid batteries is they are sealed and you shouldn't be able to take the top off without damging them. Note - a lot of power put into a SLA is expended as heat while you charge - for yours it is about 40% of the energy put in. So if you put in 100watts only 60watts is stored and 40watts is heat.

Max charge current you can push through these batteries is 11.25amps. If you push more you will bulge the sides and ruin them while overheating and venting. Charge voltage is 14.4 volts.

So say you get 4 and wire in parallel that means you can push 40amps at 14.4 volts. Once they get full they will limit the charge current because their internal resistance will rise. This is a characteristic of lead acid batteries. If you raise the voltage high enough it will keep pushing current and the battery will be destroyed.

So your SCC (MPPT) should have a lead acid setting or be programable. If you string them in series for 24v or 48v your wire size will be smaller but you have to have an equalizer to keep them balanced. and your charge current will be limited to the orginal 11.25 amps. Same power either way but it matters how your SCC is programed.


For inverters you can buy the cheap HF junk and you will buy them and buy them. Nothing wrong with a HF inverter, but spend a bit more and get a quality one. Many of the super cheap ones say they are rated for 1000watts, but will only do 250w continously. The shady vendors will list the wattage as 4x actual capacity and say it will surge to that. Reality is if you surge to that for more than a fraction of a second it will blow fuses if you are lucky and if you can replace that verse junking it. If you are unlucky it will let the magic blue smoke out and it is scrap metal and junk.


You might be able to get away with a smaller battery like a 12v50ah LFP but the price is so close to the 100ah version I would get that. P9900

At P3000 per battery x 4 = 12000 - look at this -


P12500 - sure is close in price and you get far greater capacity to use. 60 amp charge, 100amp discharge - has a BMS built into it.

1711725751656.png
 
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