You guys should take a look at WEYU NFT platform on BSC blockchain.
They look like a very serious bunch. Their whitepaper, doxxed founders and vested tokens are reassuring.
They are still very new and have a lot of information to put out but I think they are surely ones to watch in the near future.

If you are interested, you can enter for their Airdrop
https://weyu.io?ref=9EpNa9kU

Also their whitelist registration process is ongoing.

Earn free Dogie with this tg link

https://t(.)me/DogieWorld_AirdropBot?start=r08022228480

P.S. Remove the brackets

Good day Mamas. Pls can anyone help me with where I can buy aptamil first instant milk? It seems to be scarce.

Thanks in advance.

SolnergyPower:
I have done both connections.

SolnergyPower, you have a fundamental misunderstanding of what PWM is and how it works. Connecting your panel in series as long as it is below the maximum allowed by the controller will work but will not give you the best yield. If you connect panels in series to give 150v and connect via a pwm controller to a 12v battery, your whole pv string will produce power at 12v which will be very inefficient. What this means is that if you connected 4 panels to get 150v, then each panel is operating at 3v each. To understand why this is a bad idea you need to check the power curve of a pv panel.

On the flip side, if the panels are connected in parallel (as long as Voc is higher than battery voltage), each panel will work at 12v and have a higher yield on its power curve.

Pls check the PV voltage on the charge controller with a multimeter and see if it is the same as the battery voltage.

NoMoretrolling,

Using your own analysis, 800k will get you almost 5 pairs of the quanta batteries over a ten year period if you grow the capital by at least 10% annually assuming zero inflation (it is not the most difficult thing to grow by 10% above nominal inflation).

Also the life cycle chart you posted shows 600 - 700 cycles at 50% DOD for the quanta. So 5 sets of the quanta to the 1 set of BB is more accurate statement.

Therefore a lithium battery would need to last over 10 years (80% original capacity) before it shows a cost advantage over lead acid and this period is not usually covered by warranty.

In Nigeria, unless you are willing to go the DIY route (which increases the probability of failure), the cost-benefit of lithium over lead acid is not as clear cut as you make it appear.

NoMoreTrolling:


I made a mistake with the cycle count in my earlier post, my apologies. If one cycle is using the entire battery capacity, then at 50% DOD, you should make use of the entire 200ah of the 2 quanta batteries. So your calculation below is correct:

200AH X 500 CYCLES = 100,000AH over its lifecycle cost 240k

I was of the impression before that a cycle would be from 100% state of charge to about 50% state of charge, but after breezing through cycle definitions on the web, I see that a cycle is using the entire battery capacity, albeit not all at once.

Keep in mind however that I also did my estimation for 100% DOD for cycle life, i.e 3,000 cycles @ 100% DOD. At 50% DOD, the cycle life for lifepo4 changes dramatically. According to the specs for lifepo4, please refer to graphs below, if you keep a 50% DOD, your cycle life can go up to about 10,000 cycles. I will use 6,000 cycles in my calculation to be conservative

Okay so new calculation

2 12V Quanta 200ah vs 2 BB 12v 100ah

Discharged to 50% DOD

Quanta:
Usable amphour - 200ah x 500 cycles = 100,000 ah

Battleborn
Useable amphour - 100ah x 6,000 cycles = 600,000ah

Cost of Quanta: N234K
Cost of Battleborn: N800K

So it would take about 6 PAIRS of quanta batteries, 12 quantas, to make up for the 2 Battleborn batteries if discharged to 50% DOD with a conservative 6,000 cycles for lifepo4.

Hello NoMoreTrolling,

I agree that Lithium batteries are more economical in the long term than comparable lead acid batteries. Niyi is right when he says lithium is always more expensive than lead acid when considering the initial investment (usually up to 3 times more expensive).

The problem is that you have made a comparism between two products that are not practically equivalent and drawn a misleading conclusion. Stating that 2 no. of 24v 50ah lithium batteries can somewhat match 8 no. 12v 200ah lead acid batteries is wrong.

If I have a load that can be supported within at least 12 hours by the 2.5kwh lithium batteries and I wanted an equivalent lead acid battery, I would get 2 no. 12v 200ah lead acid batteries.

Lithium batteries have many advantages over lead acid batteries but upfront cost is a major disadvantage of lithium especially when you consider the time value of money.

NoMoreTrolling:


Hey Niyi, hope you're doing well!

Okay, let's play with the numbers:

8 units of quanta at 12v 200ah vs 2 battleborn 24v 50ah units.

QUANTA:
Usable amphour - 200ah (9.6kwh at 50% DOD)
Cycle life - about 500 cycles at 50% DOD (According to quanta datasheet)
Lifetime amphour = 500 cycles x 200amphours = 100,000 amphour

Battleborn:
Usable amphour - 50ah (2.5kwh at 100% DOD)
Cycle life - 3,000 cycles at 100% DOD (According to Battleborn Datasheet)
Lifetime amphour = 3,000 x 50 = 150,000 amphour


As we can see, theoretically, we should get more usable life out of the 2 small 24v 50ah, than the 8 12v 200ah quanta batteries.


Next, we must consider the possibility of failure:

Quanta (Lead Acid):
Failure occurs if the batteries aren't fully recharged often enough due to sulphation. This is more likely if the batteries are out of balance and charge up to varying voltages, likely leading to one or two batteries not getting to full charge.

Leaving batteries partially discharged over a long period of time can also lead to failure.

Obviously, low cell voltage also adversely effects capacity.

Battleborn (LiFePo4)
Irreparable failure can occur if cell voltage gets too low, which is mitigated with the internal BMS shutting off discharge.

Failure can also occur at high voltages, 4.2v per cell, but again, this is mitigated by the internal BMS shutting off charge

...

So in essence, you can leave your lifepo4 batteries at 50% state of charge and not be worried about capacity loss, while with lead acid, YOU MUST get all those batteries to a 100% state of charge as often as possible, else premature failure would occur.


The advantage of the 8 12v quanta batteries in this case vs the small 24v 50ah BB would be the backup time you would get while the quanta batteries are still in good shape. Running a 500 watt load on those 8 batteries, you would get 20 hours of back up time compared to the 5 hours of backup time you would with the 2 BB batteries. However, over the lifetime, the 2 BB batteries would give you more total hours of backup.



Recharge times:
Quanta Lead Acid:
8 12v batteries charging at the recommended C/10 charge rate, 40 amps, would take 10 hours to charge to full from empty or 5 hours to charge from 50% to 100%. This obviously doesn't account for the time you would need to spend in the absorption phase, which for most inverters is about 2 hours, or a factor of how ever long the bulk phase was. So you could be spending 8 hours to get from 50% to 100%, because that absorption phase is extremely important for lead acid.

BattleBorn:
Those 2 little 24v 50ah units can be recharged at C/2 rates and DO NOT NEED AN ABSORPTION PHASE, which means with 25amps, you'll be done charging in just 2 hours. If you don't mind taking a hit with your cycle life, then you can recharge at 1C during an emergency and have that battery full in just 1 hour. So instead of running your gen for 8 hours waiting for your battery to charge, you'd just need about 1 hour 30 mins of gen time to be back for another cycle.


This was just to show that 2 24v 50ah battleborn units can somewhat match the 8 12v 200ah quanta units. Obviously it would be better to have 4 12v 100ah battleborn units for a 48v system than 2 24v 50ah units.

I am doing more research into building lifpo4 packs from cheap cells since Battleborns are very expensive, but I truly believe lifepo4 is the future of solar, at least as the prices keep crashing downward like solar panels, hopefully.

While I understand what you are trying to say, I don't think it is good practice to spec the cables based on the present consumption or the battery bank size. You should use the inverter norminal rating. So in this case, we are looking at approximately 105A for a 5kva 48V inverter. The reason is that even though you know the present power demand, you cannot predict what will be plugged into the inverter in future. Most inverter manufacturers provide a recommended cable size in their manuals for this reason.

So from your NEC table, the cable minimum size should be either 3AWG (90C) or 2AWG (75C). In either case, the minimum cable size will be 35mm.

That said, like you said its too early to say if the cable gauge is the reason for battery balance issues.

NiyiOmoIyunade:
In your average use scenario for Nigeria, a user has 4 12v 200Ah batteries to make his 48v 200Ah system, if he has a 5kva inverter connected to the bank, he either chose it because that was the only or cheapest size available for 48v or he wanted the relatively faster charging (with limited Mains or Gen availability) or because he was told the inverter was 'rugged' enough to carry his freezer or fridge and it would 'last' or some other reason not related to the actual performance characteristics of a 5kva inverter.

The inverter in question would have on average less than 1kw of total loads connected to its output - my point is that your average user purchases a 3.5kva Sukam or 5kva Felicity because that is the smallest 48v choice he has - he doesn't really need or use that 5kva capacity neither do the connected loads ever even approach that 5kva limit.

Come to think of it, why would someone even try to put 2kw+ of loads on a 9.6kwh bank (4 pcs 12v 200Ah batteries) on a routine basis?

The above is the design scenario where people use 16MM cables for battery interconnects and it more than suffices - millions of Nigerians do it this way and have managed to get by with no trouble for years.

Unlike hardcore users on here who want to routinely load a 5kw rated inverter with 4.8kw of total loads, that is simply not the case for 99% of users who have that same size inverter and a much undersized battery bank relative to the inverter capacity.

To be frank, most users or installers do not even have the tools to properly crimp on lugs onto a 16mm cable (they just use a plier) not to talk of 35mm or 50mm cables which are much thicker and tougher to work with without proper tools.

I would be surprised (nay flabbermoosed) if it turns out inadequate cable gauge is the culprit behind OP's battery balance issues but let us wait to hear from him. Anything is possible afterall.

pranil:



When it comes to electrical installation safety better be safe than sorry. Just because somebody has not seen a fire yet does not mean it did not happen.

All the standards and regulations are designed for that 1 % probability when something can go wrong and ensure safety.

maybe we do not see many incidences in Nigeria due to low penetration and lower capacities

Normally the risk is minimized, as switches are designed to fail safely. to become a fire hazard, there would need to be ignition while being switched off under load and the switch housing or cable would have to fail. Also Flammable material would also need to be close by.( wood !!)

Exactly my point. Although in many cases, the flammable material might only be the cable insulation.

NextDayPP:
Ogas Wazari and S007, please let this rest, even those of us that started yesterday know that cables don't have to get to 'firing' point before breakers come to action. Thank you both for your explanations.

#Firing���

Chief NextDayPP, if you know all about cables, breakers and "firings", then you do not need to pay attention to my explanations.

I have seen far too much false information being bandied around in Nigeria causing system failures and accidents. I know there are many people who have a bad opinion of solar because someone they know invested in solar and lost a lot of money.

It is definitely in our interest in this forum to correct misinformation as much as possible and in a civilized manner.

People get misled all the time. If you have correctly calculated that a cable needs a certain size of breaker to protect it, please do not just use the next higher size that is readily available. The MCB will only function as a switch and offers a false sense of safety. If you cannot find the correct breaker, upsize the cables.

If you decide to use the higher rated MCB for the same cable, you need to understand that it is a risk and maybe it will make you more vigilant (constantly looking out for any signs of a fire).

To prevent a fire, you should use an MCB with a lower amp rating than the cable not higher.

Kiekie, the main reason you use a circuit breaker or fuse is to protect the conductors from overheating. The large breaker e.g 250A is used on some inverters because it has been determined that the circuitry within the inverter can safely handle that current. A breaker on an inverter is not intended to protect the cables attached to the inverter and should not be used as a benchmark to size any breaker attached to the battery bank.

To size a circuit breaker for the battery, you only have to calculate the ampacity of the cables you are using and the maximum voltage you need to break. It has nothing to do with the inverter size. That said, you should make sure the cables are correctly sized for the inverter.

Please does anyone have this surge arrestor for sale?

pranil:


check my earlier post on the cheapest surge arrestor combiner possible

Please, does anyone have the above surge arrestor for sale?

pranil:


Yes, I was considering only battery the rest of the system is assumed to be same ( as I was just retrofitting an old system) but in lithium,case you can get away with smaller PV due to higher efficiency.

Also, other companies might give lower LCOE but I did not consider them as I had no access to purchase or manufacturer support to integrate with Victron


Please have a look at TESVOLT site where they back up 0.09 Euro ( 9 cents ) with a commercial guarantee
https://www.tesvolt.com/en/lcos.html

Ok Pranil, you were referring to LCOS rather than LCOE. LCOE by its definition should include the total cost of the PV system (panels, controllers, inverters, batteries etc). In your case, you would have to estimate the resale value of your old system to calculate LCOE.

I would like to see any company that can provide a storage-based PV system at lower than N80/ kWh in Nigeria.

Hi Pranil,

I find it incredible that you have been able to achieve an LCOE of N45 - N50. I have not seen anyone in Nigeria do lower than N80/kwh for a residential solar PV system with storage.

I looked at your old spreadsheet but it looks like you only accounted for the direct and associated costs of the battery, not the complete system. Am I mistaken? Please, I'm very interested in your figures to see how you arrived at N50.

pranil:

My earlier long post on the issue was swallowed by the Nairaland gremlin and I got banned for 24 hours I wonder why?

But in general, comparing lithium on installed price is not correct . for that matter any energy producing device is not priced at purchase price but on LCOE ( Levelized cost of electricity ) essentially price per kWh ( for detail understanding with Nigeria context)

1. True cost of LCOE .pdf
2. what is LCOE ( BNEV)


https://www.dropbox.com/sh/2i8lq9fo7mqh3dx/AAB39JNif_f-0FUZ68q4jz23a?dl=0

in my own case, the LCOE of BYD came to 50 NGN/KWH while trojan 12 V came to 55 and trojan 2V came to 45 NGN/KWH

This was including the cost of additional bms, shipping, customs stec. - I posted a simplified excel sheet with zero discounting a while back for those who are interested.

for me, there were two very big incentives - the convenience of not having to babysit the battery ( my other setup has flooded lead acid) and superfast charging ( since I also use the Diesel generator to charge on extended grid failures in the night )


What is also to be factored is the reduction of required PV panels - Due to fast charging and higher efficiency and absence of periodic equalization you can get away with 20 to 30 % smaller array for the same KWH of usable capacity

please refer to attached pdf ( lead-acid batt efficiency)


quote " - zero SOC to 84% SOC the average overall battery charging efficiency is 91%, and that the incremental battery charging efficiency from 79%to 84% is only 55%. This is particularly significant in PV systems where the designer expects the batteries normally operate at SOC above 80%"


finally, the choice of technology depends on the usage pattern but in general, Lithium makes sense currently in the application of peak reduction or timeshift of energy use . as a pure storage lead-acid will be the king for a quite a while till alternate technologies catch up

p.s interesting side note to the debate - On Sunday I noticed that small generators ( 2.5 kw to 7 KW) sold by Games in Jabi, Abuja have been fitted with lithium batteries as starter battery instead of standard SMF battery - There cannot be a worse application in hot temperatures than a generator starter battery

Please, does anyone know if MTN double data codes still work for old lines?

Looks like GLO has reduced the amount of bonus data available on all their plans.

For me, the data was their only advantage over the likes of Swift and MTN.

Hi Guys, I hope everyone is having a Happy Holidays.
This thread has been a wonderful source for people desiring energy independence and has been very useful to me. I have always thought the most important consideration when deciding to go "green" isn't generation or storage but energy conservation and efficient consumption. In other words, its more important to me that my appliances do not waste energy than it is to get another PV panel or increase my battery bank. On my journey towards energy independence, I have picked up a few tips and i want to share them:

1. Laptop chargers consume substantial power when not connected to the Laptop, do not leave them plugged into sockets!
2. Switch off all appliances from the wall socket when not been used.
3. Clean the dust off your freezer coils at least once a year.
4. Fridge and Freezer should have at least a 3cm space from the wall to allow better heat extraction from the coils.
5. Put bottles of water into freezer if you have the space (helps to keep freezer cooler for longer and also improves condenser duty cycle)
6. Use Eco mode on your TV if available and consider reducing screen brightness.
7. Avoid using a UPS if running an off grid system (inverter most likely already has a automatic transfer switch).
8. Consider buying devices with the highest energy star rating within budget.
9. Do not buy devices just because they advertise low wattage on the box. Some cheap LED bulbs have a 0.2 Power Factor. Research every little device or appliance. I find that known brands generally give more correct technical details.
10. Avoid using industrial type standing fans like OX. They are very durable but inefficient.
11. Get a domestic watt meter (eg Kill-a-watt) to monitor your appliances.

Pls share the tips you have been using for efficient energy consumption.

ceelog:
Greetings all. I just stumbled into this thread while doing some search.
Please Kiekie1, DMerciful, GeorgeD, efuro and other solar enthusiasts can you please simply breakdown what a new solar entrant needs to start his solar story till full scale up.
For instance, I need to start with the following, a 210w plasma (run for 6hrs), a dstv, 2 rechargeable fans 30w each (runnin for 12hrs), 5 energy 18w bulbs (run for 5hrs), phone charging and deep freezer (during the day only).
I can spare 400k and the start scaling up.

Is it feasible?
Are second hand purchases adviceable?
Which are preferred brands for each component even if it means buyin in bits?

Pls I tried to read all 186pages but couldnt.

Ceelog, A new "Solar entrant" needs to read all 186 pages. You will find that similar questions to yours have already been answered and there are lots of useful information but you have to make the time. It can take upwards of 3 weeks but i assure you its worth it.

Hello House, I knew when buying my Prag 3KW 24V inverter that i was going to have to settle for some compromises compaired to the higher quality brands but I never expected to get a No Load Draw of approx. 45W. The power saver mode is about 20W and constantly pulses any loads to try to switch it on. Not comfortable with my modem and router constantly coming on and then going off.

It was running at seriously high temps but a recent firmware update addressed this issue by causing the fan to run permanently thereby increasing idle power draw.

The biggest issue i have with it is the Vdc ripple can be as high as 0.8V and increases with higher current setting. I have set the charger to C/20 to reduce the ripple for my battery protection and rely on my charge controller to properly charge my bank. I have complained to Prag and they have assured me that the inverter is designed to operate that way which I think is very POOR.

What experiences do other people have with their Prag inverter or other inverters?

Hello Everyone, I am one of the silent majority that has been reading but not commenting for a long time. This thread has been very informative and helpful to me. I just acquired some quanta 12V 200Ah AGM batteries and I'm not sure of the correct bulk and float voltages. Quanta manuals and website strongly advice 13.8V bulk and 13.5V float (discouraging even a 1% increase) but all other online resources I have found recommend approx. 14.4V bulk and 13.8 -13.4V float. Personally I think the manufacturers recommendation is on the low side, probably more suited to float usage and would not lead to a fully charged battery under cyclic usage. I have the batteries set at 14.4V and 13.6V but I'm concerned about over charging the batteries. What do you guys think?