Solar panels to generate electricity

windeguy

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I looked into the Tesla power wall and and I would need 3. Estimated shipping, taxes and parts with my installing came to around $20k+.
As I remember, they have built in inverter and maybe. (?) Solar controllers. But they do not have an automatic generator support system.
If I was starting new, I'd really consider it. But doing away with my 8Kw 120/240 V inverter system (integrated with controllers, grid and gerator) that handles everything and I can interact via phone and computer, is a little much to replace.

The Dyno batteries are about the same price as T105s.
The BIG difference is the charging with boiling NOT recommended. Fully charged at 57.6 V. That saves a heck of a lot of amps, time, watering and acid cleanup that the T105s needed.
Approx same size and weight.
Our car mechanic (15 years) got them for us so don't know where he got them.
Will share his name and number in private mail only.
It is unusual that using virtually the same technology, the batteries have different specs for being fully charged and equalization is not recommended. Perhaps the Dyno batteries are a bit different in construction than standard wet deep cycle lead acid batteries.

Some additional info I learned directly from Trojan Tech Support: When I spoke to Trojan's technical support people years ago, I was using my batteries for back up nearly every day because we got less than 12 hours of street power back in the early 2000's . There was never a time I had power on long enough to perform an equalize cycle. I was told by Trojan tech support that my heavy use of the batteries was already distributing the acid throughout the battery and one purpose of the equalization cycle was to evenly distribute the acid so it does not corrode the plates and cause an early failure of the battery. He told me equalization should only be performed if specific gravity measurements were different by a certain amount between the cells. I don't recall what that difference was, but I think it is part of Trojan's battery information on their web site, or a quick call to them would provide the answers.

Another point, when a chain of batteries has a battery at a radically different voltage than the rest of the chain, it is probably a good idea to try and equalize the batteries , but specific gravity measurements will lead you directly to the battery cell that is the problem. That out of spec battery is soon going to cause stress and failure of the other batteries.

I have tried every battery I could find in the DR, and ended up using Trojan T105's. They seem to perform best in the punishing tropical temperatures.

Good luck with DYNO. I had seen them for sale but didn't bite. Since you use them daily as solar back up, the EQ cycles are likely to be less needed for any lead acid style deep cycle battery, but why they never recommend it is puzzling.
 

34Santiago

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May 8, 2021
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Some thoughts to reduce the electrical use. Put the hot water heater on a switch, remove a/c fridge microwave, washing machine from the auxiliary grid, never use an iron while on the grid, put a slightly empty gallon water jug in the freezer etc. With four batteries and my 20 year old inverter I can easily make it to 8 hours without house power, Make sure you check the levels in your batteries at least once a week.
 
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Sailor51

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Oct 30, 2018
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Trojan and Dyno's mentioned above are deep cycle golf cart style batteries. Car batteries won't last long for backup be it solar or grid use for charging.

Lithium Ion batteries are indeed a pricey option. Probably far more pricey in the DR than in the US.

Trojan and Dyno's mentioned above are deep cycle golf cart style batteries. Car batteries won't last long for backup be it solar or grid use for charging.

Lithium Ion batteries are indeed a pricey option. Probably far more pricey in the DR than in the US.

Trojan and Dyno's mentioned above are deep cycle golf cart style batteries. Car batteries won't last long for backup be it solar or grid use for charging.

Lithium Ion batteries are indeed a pricey option. Probably far more pricey in the DR than in the US.
Thanx, wasn't familiar with the names.
 

reilleyp

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Dec 12, 2006
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Look up LiFePo4 batteries. They are now priced at less than the Trojans when you factor in that you can drain them down to 10%. The Trojans should only be drained to 50%. They also claim to last between 10-20 years vs only 5 sometimes for Trojans.
 

windeguy

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Look up LiFePo4 batteries. They are now priced at less than the Trojans when you factor in that you can drain them down to 10%. The Trojans should only be drained to 50%. They also claim to last between 10-20 years vs only 5 sometimes for Trojans.
They had better last longer than that:

270 Ah 12V LiFePO4 Deep Cycle 8D Battery​

$2,800.00

Imagine that price landed in the DR! I would only need 4 of them for at least $11,200 US to replace my 8 Trojan T105's

Those 8 Trojan T105's were 64,000 RD ($1,104 US) in May of 2020.
 
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reilleyp

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Dec 12, 2006
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I am getting 16 3.2 volt with 420 ah each for a total of about 20 kWh. The price was around $3000 including the BMS. (Battery manager.). That is a lot of power for $3000. No need to maintain battery acid.
 

windeguy

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I am getting 16 3.2 volt with 420 ah each for a total of about 20 kWh. The price was around $3000 including the BMS. (Battery manager.). That is a lot of power for $3000. No need to maintain battery acid.
Care to mention the source and model numbers of the batteries and BMS?

And I wonder what inverter/charger profile is compatible with such batteries. ( I don't have a solar system, just grid backup using an inverter/charger).
 

windeguy

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You can use a AC to DC lead acid charger powered from mains power, as charge efficiency and duration are less of a concern, it must not have automatic desulphation or equalisation modes. If it does, do not use it as there is a high chance of damage to the cells or battery. This can have significant reduction in battery longevity. If it has a simple bulk/absorption/float charge profile, then it can be used to recharge the battery but must be disconnected once charged and not left in trickle charge/maintenance mode. It must also have a maximum output voltage of 14.4-14.6V. When it comes to DCDC chargers and solar controllers, you must change these to LiFePO4 specific models. Efficient use of the limited solar wattage and sunlight hours per day or limited hours of driving with charge from the alternator is critical . You need to make the most of the power from these sources.

Ultimately, if it was as simple as using lead acid chargers, then the likes of REDARC, Enerdrive, Victron, Projecta, Intervolt and every other charger supplier in the country that make LiFePO4 specific chargers would not have spent tens/hundreds of thousands of dollars to develop LiFePO4 specific models.
 

reilleyp

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reilleyp

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AliExpress.com. I cannot find the exact thing I boil ugh the but these are close.

NEW 8pcs 3.2V 420Ah lifepo4 battery DIY 12V24v 420AH Rechargeable battery pack for Electric car RV Solar Energy Tax Free Grade A
Do a search on something like this.
Sorry for all the typos. My auto correct is suddenly auto INcorrect
 

windeguy

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reilleyp

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ese tipo

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Apr 12, 2019
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Happy 4th all.Wanted to throw my 2cents in on this great discussion.I am big fan of lifepo4 for many reasons... safety being being the utmost.
I follow several you tubers that specialize in batteries and the prevailing opinion seems to be lithium ,lifepo4 in particular always seems to be the
more efficient and cost-effective option.their ability in some cases to discharge down to 20 even 10 % obviously makes them much more useful than Lead Acid but if you mistakenly think that they're set it and forget it you are in for an expensive lesson.Undercharging,overchrging,and inferior charging equipment can be a death sentence for them, but with a little research and homework its is not only do-able.But makes for an awesome backup source.


Looking at those alibaba cells they are "prismatic' cells,an extremely energy dense package in a 3.2 volt cell. Great cells, but you have to exercise caution when buying from china.One of the biggies these you tubers warn about is that many alibaba sellers are offering grade B cells, which can be either used, repurposed or simply never sold and stored in a warehouse for lengthy periods, which in itself doesn't have to be a dealbreaker as self discharge on many of these cells is very low, but it still can be a caveat emptor situation at that kind of cash. Iin a nutshell some of the things to look out for are matching QR codes, testing the cells to see if they are within voltage range, and checking for warp or Bends. Many more telltale signs, just too much to list here.

If I may I'd like to suggest anyone who may be interested in lifepo4 batteries Amazon sells 12 volt 100 amphr batteries under the name ampere time, and Chin's. I suggest you go into YouTube and look up Will prowse he is the guru when it comes to solar and batteries and he has done extensive lab work and complete teardown on many of these cells and batteries and he gives you an unbiased review as most of his videos are unsponsored. The aformentioned batteries are just two of the very many cells and or batteries which he and others have tested and have done much of the legwork that you guys may be looking to do. Both of these batteries the biggest con appears to be that they don't really have a temperature sensing function which really comes into play in cold weather charging and discharging. But last I checked you really don't have snowball fights in the DR come winter time.
 

reilleyp

Well-known member
Dec 12, 2006
974
467
83
Happy 4th all.Wanted to throw my 2cents in on this great discussion.I am big fan of lifepo4 for many reasons... safety being being the utmost.
I follow several you tubers that specialize in batteries and the prevailing opinion seems to be lithium ,lifepo4 in particular always seems to be the
more efficient and cost-effective option.their ability in some cases to discharge down to 20 even 10 % obviously makes them much more useful than Lead Acid but if you mistakenly think that they're set it and forget it you are in for an expensive lesson.Undercharging,overchrging,and inferior charging equipment can be a death sentence for them, but with a little research and homework its is not only do-able.But makes for an awesome backup source.


Looking at those alibaba cells they are "prismatic' cells,an extremely energy dense package in a 3.2 volt cell. Great cells, but you have to exercise caution when buying from china.One of the biggies these you tubers warn about is that many alibaba sellers are offering grade B cells, which can be either used, repurposed or simply never sold and stored in a warehouse for lengthy periods, which in itself doesn't have to be a dealbreaker as self discharge on many of these cells is very low, but it still can be a caveat emptor situation at that kind of cash. Iin a nutshell some of the things to look out for are matching QR codes, testing the cells to see if they are within voltage range, and checking for warp or Bends. Many more telltale signs, just too much to list here.

If I may I'd like to suggest anyone who may be interested in lifepo4 batteries Amazon sells 12 volt 100 amphr batteries under the name ampere time, and Chin's. I suggest you go into YouTube and look up Will prowse he is the guru when it comes to solar and batteries and he has done extensive lab work and complete teardown on many of these cells and batteries and he gives you an unbiased review as most of his videos are unsponsored. The aformentioned batteries are just two of the very many cells and or batteries which he and others have tested and have done much of the legwork that you guys may be looking to do. Both of these batteries the biggest con appears to be that they don't really have a temperature sensing function which really comes into play in cold weather charging and discharging. But last I checked you really don't have snowball fights in the DR come winter time.
Thanks for your input. This purchase is my first and is a little bit of a gamble. Hopefully it works out.
 

DR Solar

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Nov 21, 2016
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Odd that we are getting so much new info on batteries that I didn't find 6 months ago while doing extensive search.
8D... ? I had 4 of those on my antique boat for the 32 Volt systems. 8 Volts each, about 75 lbs each and big.
Might want to double check befor you buy. Not gonna be compatible in a 12/24/36/48 volt system.
 

JD Jones

Moderator - Covid 19 in DR & North Coast
Jan 7, 2016
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Odd that we are getting so much new info on batteries that I didn't find 6 months ago while doing extensive search.
8D... ? I had 4 of those on my antique boat for the 32 Volt systems. 8 Volts each, about 75 lbs each and big.
Might want to double check befor you buy. Not gonna be compatible in a 12/24/36/48 volt system.
What about 6 x 8 = 48v wouldn't do it? Or 3 x 8 = 24v?
 

william webster

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Jan 16, 2009
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So - I have been a few weeks with Public Power charging my batteries

I do not turn it off.... float voltage ALL the time - as discussed above
Can't use much power as the inverters will shut down the charge

I have no meter yet - so no cost info.

Have had an jnstance of power outage after a lightening storm.
Solar and generator saved the day (and night)
 
Aug 21, 2007
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We ended up replacing our Trojan batteries with US Batteries, industrial size. One batter equals 2 of the trojans. Bought 18, the equivalent of 36 regular ones. So far we are very pleased with energy enough to function 24 hours. We have 3 refrigerators and a freezer, in addition to all the fans, lights, and electronics needed for a largish house and casita. The pool pump is also solar, but we have a backup electric pool pump, too, which we have been using because our water turned green when we had all those rains a few weeks ago. The only thing connected to street power is the bedroom air conditioners.

Time will tell if this is a good buy. I understand that several large businesses and factories in Santiago and Moca are using these batteries. Have seen photos.

But so far, so good.
 
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