Solar The Solar Panel Thread

[Bellbirdweb]

Drovers Tip # 38........Remove stainless steel watch before working near alternator, shorted on the battery terminal of alternator, watch welded to terminal, hand cooked, arm nearly broken, head hurt from bonnet, kids learnt some new words including the neighbors.

Wow @Drover, you’re very lucky that’s all that happened.

Saw a colleague do the same thing in a telephone exchange with a bus bar carrying 50v DC.

Burnt down to the bone and he lost the entire hand.

I never wore any watches or jewellery at work after that.

 

[Drover]

Working on a Bofors once power was needed to be on, 110v DC, head sparky didn't like how I was doing it, ignored my warning and nearly got blown over the side, fault had been reported but HE didn't believe us so didn't repair it, needless to say it was fixed later.....laughter all round.....learnt early when in doubt use back of hand to tap, still hurts but better than dead.

 

[Bellbirdweb]

Working on a Bofors once power was needed to be on, 110v DC, head sparky didn't like how I was doing it, ignored my warning and nearly got blown over the side, fault had been reported but HE didn't believe us so didn't repair it, needless to say it was fixed later.....laughter all round.....learnt early when in doubt use back of hand to tap, still hurts but better than dead.

DC is pretty nasty, doesn’t like to let go

 

[Drover]

Working on a unpowered site once, so we brought up the big old DC welder to do the welding and power our tools, soon found out that power tools with AC switches don't like DC power, turn on but couldn't shut them down, replaced with DC switches then all was good and we realized that DC arcs quite well..............nothing to do with solar power other than DC can bite if big enough.

Of course do not touch the cabling on your house hold set up, it will knock you into the yard next door, even if the mains power is turned off.

 

[Jared Dunne]

Having a second thought about my planned solar install. And wouldn't mind some input

Was initially thinking 2x 160-200w panels, appropriate regulator and 2x 100-130ah agm batteries. Pretty much a common system

But now thinking that 2x 160w panels, appropriate regulator and 2x 70ah gel batteries.
This setup will not only be lighter and cheaper, but I'm led to believe will actually have more "capacity" due to the 50% discharge ability of cell over agm's 20%.

Can anyone offer some pro tips to this setup.

 

[Drover]

I have 2 x 100a Gels, a single 200w panel with an additional 120w portable if needed, I wish they were AGMs, no drama with the Gels other than getting a replacement, they aren't an on shelf item and are dearer.
If weight is an issue just go for a 120ah with a 200w panel, no matter if an AGM or Gel if you go down to 12v a lot you've gone too far too often really.
Need to work out how much storage you need in real life then go from there. I do a lot of, off grid and reckon 200 ah of storage is a baseline for set and forget, the 100ah was okay but required vigilance.
If weight is a big issue carry less water.

I like your original set up idea.

 

[Bellbirdweb]

Having a second thought about my planned solar install. And wouldn't mind some input

Was initially thinking 2x 160-200w panels, appropriate regulator and 2x 100-130ah agm batteries. Pretty much a common system

But now thinking that 2x 160w panels, appropriate regulator and 2x 70ah gel batteries.
This setup will not only be lighter and cheaper, but I'm led to believe will actually have more "capacity" due to the 50% discharge ability of cell over agm's 20%.

Can anyone offer some pro tips to this setup.

I like your original idea better.

I have 2 x 120w solar and 2 x 100AH gel batteries and it’s a great combination.

 

[Crusty181]

Having a second thought about my planned solar install. And wouldn't mind some input

Was initially thinking 2x 160-200w panels, appropriate regulator and 2x 100-130ah agm batteries. Pretty much a common system

But now thinking that 2x 160w panels, appropriate regulator and 2x 70ah gel batteries.
This setup will not only be lighter and cheaper, but I'm led to believe will actually have more "capacity" due to the 50% discharge ability of cell over agm's 20%.

Can anyone offer some pro tips to this setup.

50% discharge for AGMs is very acceptable, there is a balance between conserving the battery and getting some reasonable use out of them. Using the batteries will take a toll, but there is a good argument thats why we have them. Ive been happily using that 50% principle with my 9 year old 120ah AGM, and I think the life span its given me is more than adequate. If it blew a valve tomorrow Id be pretty impressed with its performance and would still sing its praises. (The second battery is much newer, so its not gained family heirloom status just yet)

We travelled for 14 months with 2 x 120ah AGMs (one of them at that time 7 years old) and a single 150w roof panel. We found our setup provided just enough power for us, and we are very very power hungry with multiple tablets and phones, laptop, sat TV, multiple media players and fans. We even used the microwave off the inverter quite a few times, and my sons Xbox many times. We could have done it with a single 120ah, but like you I wanted spread the love and protect the integrity and longevity of the batteries as best I could whilst getting maximum balanced usage. We were blessed with almost constant sunshine. We had to always camp in full sunshine to make it all work, but a 10ft high 24ft long van provides a lot of shade. To be fair had we had too much overcast/wet weather the single panel would have caused us some significant grief, but we were very lucky. A second 150w panel would have solved those issues had that have happened. We regularly spent 7 days plus off the grid, but that would include some driving which would also pump up the batteries. We have an Engel in the car but that has its own 100w lightweight panel, and we don't have dual batteries in the car and never plugged the lightweight panel into the van

Good luck and let us know how you decide to set your system up

 

[Boots in Action]

I like your original idea better.

I have 2 x 120w solar and 2 x 100AH gel batteries and it’s a great combination.

Hi @Bellbirdweb , you forgot one important thing!! You now have a very efficient MPPT controller to literally produce lots and lots of amps to keep batteries charged. I do not think that an ordinary PWM controller would do the job so well. @Jared Dunne would need to have that setup to be confident like YOU are of always having sufficient power.

 

[Jared Dunne]

Out of curiosity what mppt reg are you using. If I stick with the 160ah panels I will probably run the redarc 20amp reg which is just the old school style reg. There are so many phoney mppt regs on eBay that im too scared to take the risk. On the other hand im not too keen to fork out $400+ on a top of the line one. And living in a remote W.A I don't have a local store so unfortunately I depend on online stores for nearly all of my purchases

 

[Boots in Action]

Having a second thought about my planned solar install. And wouldn't mind some input

Was initially thinking 2x 160-200w panels, appropriate regulator and 2x 100-130ah agm batteries. Pretty much a common system

But now thinking that 2x 160w panels, appropriate regulator and 2x 70ah gel batteries.
This setup will not only be lighter and cheaper, but I'm led to believe will actually have more "capacity" due to the 50% discharge ability of cell over agm's 20%.

Can anyone offer some pro tips to this setup.

Hello @Jared Dunne and welcome to the forum. I like your original idea and think that the lesser amp hours with Gel type is NOT the way to go. Have a good read of this site on comparison .
Gel vs AGM - BatteryStuff.com
https://www.batterystuff.com/kb/articles/battery-articles/gel-vs-agm.html

IMHO, your advice regarding GEL batteries is not correct. For some strange reason, Jayco persist in installing GEL batteries in their vans, even though they are dearer and not as readily available to replace. Not every battery shop has them, but AGMs are everywhere!! The GEL work okay, but there is better technology around with the latest AGMs. Gel batteries have been quoted as 60s technology. One of the members on this forum recently moved into the 21st century with Lead Crystal batteries. Much dearer, but apparently indestructible. Try Google LEAD CRYSTAL Battery for more info. Not necessarily my own thoughts, but the facts are laid out clearly on many sites including on this forum if you look back a bit.

The set up with 2 X smaller Gel may be slightly lighter but the cost of Gel batteries is a lot higher than good AGMs which @Drover has said are readily available. Also note that Gel batteries are nowhere near as robust as AGMs and require special charging rates. If you are going to run your battery capacity down to the MARGINAL 50% DOD, then 50% of @ 2 X 120 ah AGMs is approx 120amps. Do the same with the lower capacity Gel 2 X 70ah and you can only use 70amps. In fact with a quality MPPT solar controller and 1 X 120ah AGM , you would still be way ahead with the same wattage panels than with an ordinary PWM controller and 2 X 70ah Gel. Have one good AGM with 120 or 130ah capacity and put the extra money into an MPPT controller to keep your battery charged. @Drover (Sorry @Drover - you again!!!) has said before on this forum , that you can never have enough storage, and it is a matter of working out how much you are going to use verses what you may generate in good and bad conditions. And of course, your wallet. It is an expensive mistake if you do not achieve what you want. Choose carefully.

 

[Boots in Action]

Out of curiosity what mppt reg are you using. If I stick with the 160ah panels I will probably run the redarc 20amp reg which is just the old school style reg. There are so many phoney mppt regs on eBay that im too scared to take the risk. On the other hand im not too keen to fork out $400+ on a top of the line one. And living in a remote W.A I don't have a local store so unfortunately I depend on online stores for nearly all of my purchases

Again @Jared Dunne , with 2 X 160 watt panels, you would need at least a 30 amp MPPT controller. On Ebay, you can get a proper and reliable MPPT controller (Epever) for around $165.00 . There may be a few dollars more for separate remote display panel and lead and remote temp sensor. Contact @Bellbirdweb as he recently fitted one for under $200.00 and is extremely happy. I myself have a LD Tracer Dream series 30A (2 year warranty) which I bought from a company in Forster NSW on Ebay which was only $140.00 at the time. Has now gone up to nearly $200.00!! I am using 2 portable panels in series 1 X 200w and 1 X 180w. Have a good look through the posts on this forum for the proven MPPT controllers.

 

[Crusty181]

Out of curiosity what mppt reg are you using. If I stick with the 160ah panels I will probably run the redarc 20amp reg which is just the old school style reg. There are so many phoney mppt regs on eBay that im too scared to take the risk. On the other hand im not too keen to fork out $400+ on a top of the line one. And living in a remote W.A I don't have a local store so unfortunately I depend on online stores for nearly all of my purchases

Im using a 40amp Epsolar MPPT controller, around $160 on Ebay delivered. There are cheaper 30amp and 20amp models, youll just need to make a parallel or series preference decision and check the specs of each unit to make sure its suitable. I went with the biggest offering, the 40amp model, not for the amps but the voltage capacity which will cope with 3 x 150w panels in series so kinda of future proofs any change of system direction down the track.

 

[Drover]

Not only do you have to have a controller that will carry the amps, I prefer 30 or more but you have to make sure the controller no matter what breed will handle the total wattage of the panels as some are limited to 300 while others exceed 400w........................

 

[Boots in Action]

Im using a 40amp Epsolar MPPT controller, around $160 on Ebay delivered. There are cheaper 30amp and 20amp models, youll just need to make a parallel or series preference decision and check the specs of each unit to make sure its suitable. I went with the biggest offering, the 40amp model, not for the amps but the voltage capacity which will cope with 3 x 150w panels in series so kinda of future proofs any change of system direction down the track.

Hi @Crusty181 , you seem to all over it. Whilst it is important that the controller is able to handle the greater current that your MPPT controller may generate, one of the other very important areas if connecting in SERIES, (not so important if connecting in parallel as probably only 18 to 20V) is the max voltage input. With each panel producing around 22.0V on OCV and around 18.0V working voltage, one could connect up 4 panels in series and still be under the limit of say 100V which most good MPPT controllers have. My LD Tracer Dream is rated at 30A and up to 100V.

A 72.0V input (4 panels in SERIES) even at a lowly 6.0A (the lowest output in the series!) 420 W is a lot of watts for the MPPT controller to handle and convert to battery voltage. No need to worry about voltage drop in the INPUT wiring to the controller. But a very good reason to have the connecting wire between the controller and battery/ies as short as possible and able to carry the much heavier current - more than 30 Amps!!!

 

[Crusty181]

Hi @Crusty181 , you seem to all over it. Whilst it is important that the controller is able to handle the greater current that your MPPT controller may generate, one of the other very important areas if connecting in SERIES, (not so important if connecting in parallel as probably only 18 to 20V) is the max voltage input. With each panel producing around 22.0V on OCV and around 18.0V working voltage, one could connect up 4 panels in series and still be under the limit of say 100V which most good MPPT controllers have. My LD Tracer Dream is rated at 30A and up to 100V.

A 72.0V input (4 panels in SERIES) even at a lowly 6.0A (the lowest output in the series!) 420 W is a lot of watts for the MPPT controller to handle and convert to battery voltage. No need to worry about voltage drop in the INPUT wiring to the controller. But a very good reason to have the connecting wire between the controller and battery/ies as short as possible and able to carry the much heavier current - more than 30 Amps!!!

Only thanks to your guys. In fact, all you tech heads should take some comfort in the knowledge that you have learn up at least one numb skull who is doing a valiant effort at following the mutterings and trying keeping up. 6 months ago I would have just bought any old panels I could find at the church car boot sale, plug them and expect all to be good. Im assuming that you all know what your talking about, my brain has too many Tabs open, and I cant afford BS to be taking up space

 

[Axl]

Im using a 40amp Epsolar MPPT controller, around $160 on Ebay delivered. There are cheaper 30amp and 20amp models, youll just need to make a parallel or series preference decision and check the specs of each unit to make sure its suitable. I went with the biggest offering, the 40amp model, not for the amps but the voltage capacity which will cope with 3 x 150w panels in series so kinda of future proofs any change of system direction down the track.

Can I ask where on ebay you brought this from @Crusty181? I've done a search as I want to purchase one soon and there's a guy on there selling a 40A controller and the remote display for $170. That's around $480 worth of gear something just doesn't ring true here to me.....

 

[Crusty181]

Can I ask where on ebay you brought this from @Crusty181? I've done a search as I want to purchase one soon and there's a guy on there selling a 40A controller and the remote display for $170. That's around $480 worth of gear something just doesn't ring true here to me.....

Seller : trustinchina
Current offering : https://www.ebay.com.au/itm/EPsolar...654043?hash=item3f68878edb:g:KCoAAOSw9NdXqwCz

trustinchina states local stock, and mine arrived pretty quickly so I suspect it is local. trustchina has a 40A controller advertised with remote for $182, so $170 not so outrageously cheap although there isnt any others that cheap for both. Seems to work ok, good luck with it

 

[Axl]

Seller : trustinchina
Current offering : https://www.ebay.com.au/itm/EPsolar...654043?hash=item3f68878edb:g:KCoAAOSw9NdXqwCz

trustinchina states local stock, and mine arrived pretty quickly so I suspect it is local. trustchina has a 40A controller advertised with remote for $182, so $170 not so outrageously cheap although there isnt any others that cheap for both. Seems to work ok, good luck with it

Thanks @Crusty181 that was the seller I was looking at I was just shocked at their prices. I was just about to hit go on a 20A unit from a reputable online seller for $180 when I read your post.

 

[Drover]

Have seen them for about $10 from China with free postage,,, ......., the local warehouses for these chinese mobs are pretty quick , the fella puts down his noodles, walks along a rack picks out the box and bungs it into a jiffy post bag or slaps his pre paid label on and courier picks it up, of course if it breaks don't bother going thru the, email supplier BS they won't answer just hit up Ebay for a refund/return it's way quicker........................