24V off-grid residential installation - please check my product choices

[MoBeats]

Greetings.

I'm considering using the following components for an off-grid residential solar installation in West Africa. The parts are available locally for a reasonable price:

1 X 3Kva / 2400W Felicity MPPT 60A 24V Charger / 230V Inverter - FL-IVCM3024
3 X 400W Felicity Solar Panels (41VOC 11.3A IMP) - MSD120-400W
4 X 200Ah Felicity AGM Telecom Battery - FL-GE-200AH (hoping to add an extra 4 batteries later for a total of 8 x 200Ah)

Please check my product selections and let me know if this system should work.

The local supplier also has a 48v Felicity Inverter available for sale (IVEM5048) I was considering this unit, but am leaning towards the 24V system as it it is cheaper to purchase, and it will be cheaper to scale the battery bank, adding only 2 batteries at a time, instead of 4. I was also thinking that I could scale the power, by adding an extra 24V inverter in parallel later, when more funds are available.

Thanks in advance for your comments and suggestions!

Links to products I'm planning to use:
BATTERY:

Long Lifespan Front Terminal Battery 12v 200ah Manufacturers

We provide Long Lifespan Front Terminal Battery 12v 200ah. For detailed 12V 200AH Opzv Battery information,please consult us.

www.felicitysolar.com

INVERTER:

3Kva Hybrid Inverter With MPPT 60A Controller Manufacturers

We provide 3Kva Hybrid Inverter With MPPT 60A Controller. For detailed high frequency Hybrid Inverter information,please consult us.

www.felicitysolar.com

SOLAR PANEL:

https://www.felicitysolar.com/uploadfile/downloads/M400W_1.pdf

--
Link to other 48V inverter I was considering:
ALTERNATIVE INVERTER OPTION:

500V PV INPUT 3KW Hybrid Inverter With MPPT 100A Inbuilt Manufacturers

We provide 500V PV INPUT 3KW Hybrid inverter with MPPT 100A inbuilt. For detailed 500V PV In put High frequency Hybrid Inverter information,please consult us.

www.felicitysolar.com

 

[sunshine_eggo]

Will it work? Absolutely. Will it work for what you need it for? Who knows?

Have you determined your solar availability, needed loads, consumption and properly sized the system?

Based on some typical assumptions, that system can provide:

1. 6kWh of energy per day.
2. 4.8kWh of battery backup between charges.

Generally speaking, "Telecom" batteries are typically a bad choice for a cyclic power system. They are designed primarily to sit there fully charged for days/weeks/months at a time and then provide very temporary high current backup power until a generator or other secondary power system can be brought online.

I would want the answer to the following question:

At a C10 discharge rate, what is the cycle life of the batteries.

Quality AGM batteries will typically be 900-1200cycles until they deteriorate to 70-80% rated capacity. This means that you may need to replace them every 3-4 years.

"GE" in the battery number may indicate "GEL," and other websites list that part number as a GEL. 14.4-14.6V charge voltage for a GEL battery is too high.

 

[Substrate]

I'm with sunshine_eggo on this one.

Even though GE is in the model number, a later description says agm. But heh, sometimes manufacturers just don't care. Better hammer them on that to find out if they are gel or agm. Some distributors don't know either.

True telco batteries are designed to sit on float, but in exceptional circumstances, they can be cycled, but not for long. Usually only long enough to get through the outage being run at the higher CV's being rapidly recharged by a generator, but cycle life is atrocious. Once the event is over, they are handed off to DIY types. (recycled and replaced usually).

What I *think* these are, are just general-purpose conventional AGM's, in a telco-type case for convenience. But lacking any real documentation to prove if they are telco batteries or not, makes this hard to determine.

One thing for sure - based on your location, you had better use a remote-temperature probe from the SCC to the batteries!

Planning to add more lead later? Like what - in a month or a year? Unlike LFP, this virtually guarantees that you will soon be out of balance with no way to keep them even. The batteries already in use will degrade the new ones.

I don't see any charger in your shopping cart. You need to charge each one of these individually *first* before you put them into your eventual series/parallel service. Solar alone won't achieve a good first initial charge, unless you have a spare week each to let them sit and float.

One shouldn't just think they can piecemeal a lead-acid based installation when and if funds become available. It needs to be purchased all up front at once. Unless you are planning on a non-critical backyard plaything, which this project doesn't look to be.

Honestly - save up some way to go with LiFePO4 if you can. You can piecemeal it within reason later. Going AGM now in this system, will actually cost you more in the long run, especially if you plan to just "add" more lead later.

 

[MoBeats]

Thanks for your replies. I will ask the manufacturer for more details about the battery. The website states:

"Long Lifespan Front Terminal Battery 12v 200ah
High Reliability and Quality lead acid battery with Longer Service Life , it is the best choice of solar system"

and

"Maintenance-Free ,Absorbent Glass Mat Technology"

Hence I'm guessing that it is indeed a regular AGM battery in a telco-type case as Substrate suggested.

As for when I intend to add more batteries - maybe around 2 or 3 weeks after the initial installation. Funding is driven by my personal cash flow, and I need to focus on getting the panels and inverter to enable my electrician to start job, which needs to completed within the next month, to coincide with the overall construction schedule. (this is for a new build property).

Re. LiFePO4, we haven't been able to source suitable batteries at an affordable price locally, and we don't have enough time to import from China right now. Hopefully in the future we can upgrade to a larger 48V system with expanded storage capacity, at which point we will go for LiFePO4.

Re. power requirements, based on rough calculations, we will typically use around 9KWh a day, hence 3 x 400W panels going into 8 x 200Ah of lead should almost be enough, and we can turn a petrol generator on for a while in the evening if required.

Thanks for mentioning about charging the batteries individually before connecting to the charger/inverter unit, I will bear that in mind!

 

[littleharbor2]

Thanks for your replies. I will ask the manufacturer for more details about the battery. The website states:

"Long Lifespan Front Terminal Battery 12v 200ah
High Reliability and Quality lead acid battery with Longer Service Life , it is the best choice of solar system"

and

"Maintenance-Free ,Absorbent Glass Mat Technology"

Hence I'm guessing that it is indeed a regular AGM battery in a telco-type case as Substrate suggested.

As for when I intend to add more batteries - maybe around 2 or 3 weeks after the initial installation. Funding is driven by my personal cash flow, and I need to focus on getting the panels and inverter to enable my electrician to start job, which needs to completed within the next month, to coincide with the overall construction schedule. (this is for a new build property).

Re. LiFePO4, we haven't been able to source suitable batteries at an affordable price locally, and we don't have enough time to import from China right now. Hopefully in the future we can upgrade to a larger 48V system with expanded storage capacity, at which point we will go for LiFePO4.

Re. power requirements, based on rough calculations, we will typically use around 9KWh a day, hence 3 x 400W panels going into 8 x 200Ah of lead should almost be enough, and we can turn a petrol generator on for a while in the evening if required.

Thanks for mentioning about charging the batteries individually before connecting to the charger/inverter unit, I will bear that in mind!

Be sure to add all fusing/circuit breakers AND a set of Bus Bars which will make expanding your battery easier.