makavele:


I do not like guesswork.
Please place an ammeter between charge controller and battery bank;
and let us know what you get,
Then place between battery bank and inverter and let us know what you get too . .
before you do this, please ensure the CC is supplying more than the c10 or c20 current
thanks

NiyiOmoIyunade:
I checked online and the Yohako MPPT CC appears to be rated at input VoC 96v and max current 80a - this is probably the reason why your installer used a 2 panels in series config for you.

The challenge is now that this controller is mismatched for your application as you are using a 48v nominal system. MPPT requires some 'voltage headroom' to operate properly e.g a 48v nominal system will charge batteries anywhere from 56v to 62v (allowing for desulfation voltages) - at the panel side you will need at least 90volts to give sufficient headroom for the Charge Controller to 'boost' current and realise MPPT benefits - with 24v nominal panels, you need a minimum of 3 panels in series to achieve a useable MPPT voltage range for a 48v nominal battery bank - unfortunately, you will fry the Yohako at this voltage level.

Its either you switch to a 24v inverter and keep the Yohako as is OR you set your panels as 3 in series and change to a different controller capable of at least 150vdc e.g Chinco EP Solar/Fangpusun or the venerable MorningStar or Midnite Solar, Magnum e.t.c

As it is now you have an MPPT CC but operating like or worse than a PWM because it is not suitable for your application

You still have to ensure your panels face either South or West or East (some folks on here do North but I have no idea how that works) in that order of preference, your panel mount tilt/angle is relatively flat, no shading on the panels, properly sized cables e.t.c to be sure you have captured all angles.

But clearly, it appears your issue is a poorly designed/mismatched system and you will need some tweaking to get it right.

mank1234:

What I posted has been proven scientifically and not guess work. Recheck your physics or electrical theories. The net current is independent of the charge rate so long as there's a difference in current drawn and current put in. So no need to mention C10 or C20.

In retrospect, your assumptions is more of guess work.

makavele:


People that know me know I am more of a practical man ..
I will post a video tomorrow concerning this;
at least not to argue but for knowledge purposes

makavele:


People that know me know I am more of a practical man ..
I will post a video tomorrow concerning this;
at least not to argue but for knowledge purposes

mank1234:


Ok. Tomorrow will be here soon.

NiyiOmoIyunade:
I checked online and the Yohako MPPT CC appears to be rated at input VoC 96v and max current 80a - this is probably the reason why your installer used a 2 panels in series config for you.

The challenge is now that this controller is mismatched for your application as you are using a 48v nominal system. MPPT requires some 'voltage headroom' to operate properly e.g a 48v nominal system will charge batteries anywhere from 56v to 62v (allowing for desulfation voltages) - at the panel side you will need at least 90volts to give sufficient headroom for the Charge Controller to 'boost' current and realise MPPT benefits - with 24v nominal panels, you need a minimum of 3 panels in series to achieve a useable MPPT voltage range for a 48v nominal battery bank - unfortunately, you will fry the Yohako at this voltage level.

Its either you switch to a 24v inverter and keep the Yohako as is OR you set your panels as 3 in series and change to a different controller capable of at least 150vdc e.g Chinco EP Solar/Fangpusun or the venerable MorningStar or Midnite Solar, Magnum e.t.c

As it is now you have an MPPT CC but operating like or worse than a PWM because it is not suitable for your application

You still have to ensure your panels face either South or West or East (some folks on here do North but I have no idea how that works) in that order of preference, your panel mount tilt/angle is relatively flat, no shading on the panels, properly sized cables e.t.c to be sure you have captured all angles.

But clearly, it appears your issue is a poorly designed/mismatched system and you will need some tweaking to get it right.

fernado56:
Hello House, I have been following this thread for long and i give kudos to all members for the enlightment so far, i want to Install a Solar System to Complement PHCN and Here are My Loads wattage Below , Please Kindly Advice on Nos of Panel and Batteries , I was thinking 800w, 40A pwm , and 4 Pcs , 12v 100AH, 24v 1.2/1.5kv inverter. Please all the expert kindly advise me .Also any reliable Installer that can give after installation service at ibadan.

Call/watapp 08117398294 for discussion. Tx
.'


Refrigerator watts = WattHours =60w ........ for 5hours...................300w/hr
Television watts = WattHours = 70w.......For 8 hours daily............ 560w/hr
DVD home theatre WattHours = 110.......For 7 hours daily............ 770w/hr
House lights led watts = WattHours= 65w... for 6 hours daily........... 390w/hr
House lights others watts = WattHours= 120w... for 2 hours daily........... 240w/hr
Computer system = WattHours = 65w....... For 6 Hours daily........... 390w/hr
Misc items watts = WattHours = 50w ..... For 2 Hours daily........... 100w/hr

Summary of WattHours required
Total daily WattHours required = 2750w/hr

kiekie1:


Please YOHAKO solar charge controllers have various specs & ratings ... I believe all mppt device comes with a user manual , he can simply send the nameplate/sticker of his own to ascertain further solutions here !

makavele:


People that know me know I am more of a practical man ..
I will post a video tomorrow concerning this;
at least not to argue but for knowledge purposes

NiyiOmoIyunade:
No magic in this thing - the OP can't have MPPT like performance with a 48v nominal battery bank if he has
his panels setup as two 24v nominal panels in series - he needs a minimum of three 24v nominal panels in series to get sufficient array voltage to drive the controller's MPPT function - except his panels are the on-grid type with VmP & VoC above 40v and even then two panels would be a stretch.

The best the user manual can tell us now is that he has a 150v or 180v capable controller and he can then simply change his panel config to 3 panels in series and begin to enjoy.

mank1234:

What I posted has been proven scientifically and not guess work. Recheck your physics or electrical theories. The net current is independent of the charge rate so long as there's a difference in current drawn and current put in. So no need to mention C10 or C20.

In retrospect, your assumptions is more of guess work.

JUO:
some people are just bad from the womb. imagine selling 40a epever cc to someone, after receiving it he decided he doesn't want it again. I refunded him only him swap the cc I sent him and sent me scrap/dead cc.

JUO:
some people are just bad from the womb. imagine selling 40a epever cc to someone, after receiving it he decided he doesn't want it again. I refunded him only him swap the cc I sent him and sent me scrap/dead cc.

NiyiOmoIyunade:
So sorry bro! There will always be bad eggs like these whose wicked actions will want to make someone unnecessarily harsh on other good people.

Just see if you can get him to send back the real thing peacefully and subsequent transactions only make refunds as seller after you have received your goods back in perfect condition.

Your current model of trusting people and sending refunds ahead may be too good for the current Nigeria.

kiekie1:


Lol , Oga u dey observe this thread too ? See link below ;
https://www.nairaland.com/4166130/infinitikoncept-refused-released-goods/16

You must really be a practical man.

DUNKA:
House please a silly question

If you go into float everyday on your system can one automatically assume that your batteries are being fully recharged everyday?

DUNKA:
House please a silly question

If you go into float everyday on your system can one automatically assume that your batteries are being fully recharged everyday?

makavele:


You can assume so; yes; but do not be decieved by what the charge controller is telling you. . .
The only way to know a battery's true state of charge is to check its S.G. ( specific gravity)
This is why i want to delve into flooded batts now as against SMF batts

NiyiOmoIyunade:
Yes you can assume so. However the reality in my experience is very different especially if you have your battery bank setup in series. All will be going well for a year or two and then bam!!! suddenly backup time drops and you check and realise one or two batteries are failing and weaker than the rest. This is the reason why when one changes out a battery bank of say four 12v batteries you will usually find two batteries that are still very good in the bank and one or two that are average/bad. Thanks

Here is the thing - there is a fundamental assumption that when you receive say 4 brand new batteries of a given brand X they were all manufactured at about thesame time and from thesame batch, are all at the exact same state of charge and of roughly the exact same capacity - the reality is different with manufacturer variations within and across different batches, time in transit and storage with the attendant self discharge/loss of some charge or capacity, batteries from different batches and ages mixed together at the warehouse and then shipped to you when you purchase.

The net effect is that the those four brand new batteries you receive are all very different internally and are at different chemical and electrical states. Assuming good manufacturer process quality and all are roughly thesame capacity, you may receive one battery at 97% state of charge, one at 89%, one at 92% and the last one at 80%. If you checked the voltage of all these batteries they would all test between 12.8 and 13.1 indicating a 'full charge'

Cobble all these batteries together in series and fire up your inverter and the slow death begins. The battery with the highest state of charge gets full first and maybe the next highest, at this point your inverter senses the set absorb point is reached and shifts into float. In reality the two batteries with the lowest state of charge never get a full charge - when you discharge them, the fully charged ones give up their power and say you cutoff at 50%, the undercharged ones will cutoff more deeply discharged at say 30% power left - with each charge and discharge cycle the gap widens and the undercharged batteries get less and less of a full charge and sulfation slowly strangles them until when you realise that these batteries aren't performing as expected at which time it's usually too late.

The answer is to charge each new battery fully before you put it into service especially in a series config. A 48v inverter thinks it is seeing one huge 48v battery and not four 12v batteries so the installer has to work to make sure the four 12v batteries are fully charged and are as closely matched to each other in capacity as possible.

Every six months or so, isolate each battery again and give it the treatment > fully charge each battery > test capacity and select those batteries with capacity within thesame range > put back into service.

According to the research done by Victron Energy for their battery balancers, a 2% variation in initial battery capacity and/or state of charge is sufficient to slowly kill the weaker batteries from undercharging and sulfation and the stronger ones from overcharging .

These days I have gotten lazy as I grow into my old age so I would just occasionally switch my batteries from 4 in series to 4 in parallel and use a 12v inverter to charge and discharge them for like a week because I believe the batteries get closer to an equal charge in parallel. Where I wanna move to which is what I do now when clients have battery issues before warranty expiry is to clap a cheapo chinco 12v smart battery charger (Suoer) on each individual battery in a bank and let each one do it's work of giving a full charge to the battery it is connected to. No time to spend the whole day or pay multiple visits to any client

At under 20k each I now have 4 of these chargers - may do more as time goes - so we can move to site and provide the treatment quickly without changing anything in the client's setup.

Yes you can have a 48v inverter charging four batteries in series and still clamp on a 12v charger to each battery without issues so long as you do not mixup polarity. The Souer's absorb setpoint is 14.8volts so I just reduce the inverter setpoint to say 14.1 or 14.4volts during the treatment period so that the Souer does most of the charging and topping off.

So that is how I do it! I am sure by now its obvious if you go through my posts that I have pretty strange ideas about how batteries behave and should be maintained. These are the conclusions I reached based on careful study and hands on experience with various battery banks.

NiyiOmoIyunade:
Yes you can assume so. However the reality in my experience is very different especially if you have your battery bank setup in series. All will be going well for a year or two and then bam!!! suddenly backup time drops and you check and realise one or two batteries are failing and weaker than the rest. This is the reason why when one changes out a battery bank of say four 12v batteries you will usually find two batteries that are still very good in the bank and one or two that are average/bad.

Here is the thing - there is a fundamental assumption that when you receive say 4 brand new batteries of a given brand X they were all manufactured at about thesame time and from thesame batch, are all at the exact same state of charge and of roughly the exact same capacity - the reality is different with manufacturer variations within and across different batches, time in transit and storage with the attendant self discharge/loss of some charge or capacity, batteries from different batches and ages mixed together at the warehouse and then shipped to you when you purchase.

The net effect is that the those four brand new batteries you receive are all very different internally and are at different chemical and electrical states. Assuming good manufacturer process quality and all are roughly thesame capacity, you may receive one battery at 97% state of charge, one at 89%, one at 92% and the last one at 80%. If you checked the voltage of all these batteries they would all test between 12.8 and 13.1 indicating a 'full charge'

Cobble all these batteries together in series and fire up your inverter and the slow death begins. The battery with the highest state of charge gets full first and maybe the next highest, at this point your inverter senses the set absorb point is reached and shifts into float. In reality the two batteries with the lowest state of charge never get a full charge - when you discharge them, the fully charged ones give up their power and say you cutoff at 50%, the undercharged ones will cutoff more deeply discharged at say 30% power left - with each charge and discharge cycle the gap widens and the undercharged batteries get less and less of a full charge and sulfation slowly strangles them until when you realise that these batteries aren't performing as expected at which time it's usually too late.

The answer is to charge each new battery fully before you put it into service especially in a series config. A 48v inverter thinks it is seeing one huge 48v battery and not four 12v batteries so the installer has to work to make sure the four 12v batteries are fully charged and are as closely matched to each other in capacity as possible.

Every six months or so, isolate each battery again and give it the treatment > fully charge each battery > test capacity and select those batteries with capacity within thesame range > put back into service.

According to the research done by Victron Energy for their battery balancers, a 2% variation in initial battery capacity and/or state of charge is sufficient to slowly kill the weaker batteries from undercharging and sulfation and the stronger ones from overcharging .

These days I have gotten lazy as I grow into my old age so I would just occasionally switch my batteries from 4 in series to 4 in parallel and use a 12v inverter to charge and discharge them for like a week because I believe the batteries get closer to an equal charge in parallel. Where I wanna move to which is what I do now when clients have battery issues before warranty expiry is to clap a cheapo chinco 12v smart battery charger (Suoer) on each individual battery in a bank and let each one do it's work of giving a full charge to the battery it is connected to. No time to spend the whole day or pay multiple visits to any client

At under 20k each I now have 4 of these chargers - may do more as time goes - so we can move to site and provide the treatment quickly without changing anything in the client's setup.

Yes you can have a 48v inverter charging four batteries in series and still clamp on a 12v charger to each battery without issues so long as you do not mixup polarity. The Souer's absorb setpoint is 14.8volts so I just reduce the inverter setpoint to say 14.1 or 14.4volts during the treatment period so that the Souer does most of the charging and topping off.

So that is how I do it! I am sure by now its obvious if you go through my posts that I have pretty strange ideas about how batteries behave and should be maintained. These are the conclusions I reached based on careful study and hands on experience with various battery banks.

makavele:
Let me correct a misconception here . . .
Take for example a 40A mppt controller on a 600W array connected to just a single 12V 100Ah battery
On a very good day, during bulk charging the array is capable of pushing out 25-30 Amps
But we all know it is best to charge batteries at one-tenth capacity (C10) i.e. in this example 10A;
So your controller is pushing 30A, which is an overkill for the battery.
Most people, like the poster above me, believe you can add or turn on some load to reduce the current entering the battery.
This is a misconception and why is so?
1. The PV array does not directly power any load connected to the inverter/battery bank.
2. What happens is that the battery is discharging and charging at the same time albeit very fast.
3. If for example, the total load turned on is 100W; and the PV is producing 150W; what happens is that the load
will draw 100W from the battery (discharge); and at the same time the PV will pump in 100W (recharge) to the battery
to replace what is lost and 50W is used to keep the battery in float (if it is already in float);
or used to keep charging the battery if it isn't yet in float

SO back to our example, what if the CC is delivering 30A on a c10 rated battery . .
if you like turn on all the load in the world; what is happening is that . . the CC is still sending in 30A to your battery
and in turn your battery is powering the loads connected, be it 10A, 20A, 2A, 100A
If the CC amp is greater than the load, the battery stays charged up
if the load amps is greater than CC amp, the battery will start discharging even while being connected to solar.

Thanks

NiyiOmoIyunade:
Yes you can assume so. However the reality in my experience is very different especially if you have your battery bank setup in series. All will be going well for a year or two and then bam!!! suddenly backup time drops and you check and realise one or two batteries are failing and weaker than the rest. This is the reason why when one changes out a battery bank of say four 12v batteries you will usually find two batteries that are still very good in the bank and one or two that are average/bad.

Here is the thing - there is a fundamental assumption that when you receive say 4 brand new batteries of a given brand X they were all manufactured at about thesame time and from thesame batch, are all at the exact same state of charge and of roughly the exact same capacity - the reality is different with manufacturer variations within and across different batches, time in transit and storage with the attendant self discharge/loss of some charge or capacity, batteries from different batches and ages mixed together at the warehouse and then shipped to you when you purchase.

The net effect is that the those four brand new batteries you receive are all very different internally and are at different chemical and electrical states. Assuming good manufacturer process quality and all are roughly thesame capacity, you may receive one battery at 97% state of charge, one at 89%, one at 92% and the last one at 80%. If you checked the voltage of all these batteries they would all test between 12.8 and 13.1 indicating a 'full charge'

Cobble all these batteries together in series and fire up your inverter and the slow death begins. The battery with the highest state of charge gets full first and maybe the next highest, at this point your inverter senses the set absorb point is reached and shifts into float. In reality the two batteries with the lowest state of charge never get a full charge - when you discharge them, the fully charged ones give up their power and say you cutoff at 50%, the undercharged ones will cutoff more deeply discharged at say 30% power left - with each charge and discharge cycle the gap widens and the undercharged batteries get less and less of a full charge and sulfation slowly strangles them until when you realise that these batteries aren't performing as expected at which time it's usually too late.

The answer is to charge each new battery fully before you put it into service especially in a series config. A 48v inverter thinks it is seeing one huge 48v battery and not four 12v batteries so the installer has to work to make sure the four 12v batteries are fully charged and are as closely matched to each other in capacity as possible.

Every six months or so, isolate each battery again and give it the treatment > fully charge each battery > test capacity and select those batteries with capacity within thesame range > put back into service.

According to the research done by Victron Energy for their battery balancers, a 2% variation in initial battery capacity and/or state of charge is sufficient to slowly kill the weaker batteries from undercharging and sulfation and the stronger ones from overcharging .

These days I have gotten lazy as I grow into my old age so I would just occasionally switch my batteries from 4 in series to 4 in parallel and use a 12v inverter to charge and discharge them for like a week because I believe the batteries get closer to an equal charge in parallel. Where I wanna move to which is what I do now when clients have battery issues before warranty expiry is to clap a cheapo chinco 12v smart battery charger (Suoer) on each individual battery in a bank and let each one do it's work of giving a full charge to the battery it is connected to. No time to spend the whole day or pay multiple visits to any client

At under 20k each I now have 4 of these chargers - may do more as time goes - so we can move to site and provide the treatment quickly without changing anything in the client's setup.

Yes you can have a 48v inverter charging four batteries in series and still clamp on a 12v charger to each battery without issues so long as you do not mixup polarity. The Souer's absorb setpoint is 14.8volts so I just reduce the inverter setpoint to say 14.1 or 14.4volts during the treatment period so that the Souer does most of the charging and topping off.

So that is how I do it! I am sure by now its obvious if you go through my posts that I have pretty strange ideas about how batteries behave and should be maintained. These are the conclusions I reached based on careful study and hands on experience with various battery banks.

NiyiOmoIyunade:
Yes this is correct Boss. But you only have access to SG readings with flooded batteries and even then you go tire to dey check SG on a regular basis - all the hand flushing and equipment washing to rinse off the corrosive acid can become annoying

Again SG and voltage measurements are indicators that your state of charge is within a particular range. They cannot tell you the exact state of each cell e.g on my US battery L16 flooded bank I get temperature adjusted SG readings between 1.275 and 1.295 across all cells when my batteries are fully charged. Yet if I run say my 2hp AC for like 8 hours its the battery with one cell at 1.295 that collapses first

With all the charge in this world (my array can generate a max 75amps into a 360AH bank if I don't cap the output) I have not gotten the SGs to converge. In a moment of madness I even started siphoning electrolyte from the 1.295 cell into the weaker ones yet no joy

So I settled for simply clapping an individual charger on each battery on a regular basis and keeping the water topped up.

Flooded is good but as you would have seen from people's experiences on here with their Trojans and my own US Battery L16s, after a while things start to go south and they need ever more and more babysitting to keep them healthy.

As it stands now, I have given up on lead acid, our salvation now seems to be Lithium with the promise of negligible or zero sulfation/loss of capacity even at 80% depth of discharge.

bigrovar:


This assumption is wrong in theory and in practise. Electricity flows from high potential to low potential.

Scenario 1 If say your PV is producing 1000w and your load is using 1200w, 1000w goes from your CC to your load, and the reminder 200w is taken from the battery.

Scenario 2 If your battery is full and your PV can potentially produce 1000w and your load is 1000w, the load from the PV goes straight to the inverter (Your battery is completely ignored.)

Scenario 3 If your PV can potentially produce 1000w and your load is using 500w then 500w goes from PV to load and unused 500wh would become potentials.

Scenario 4 if your battery is low and your PV is producing 800w but your load is using 800w,all 800w produced by the PV goes to the load. Non is left for the battery.

Remember like I said, electricity moves from high potential to low potential.. The lowest potential in all the above scenario is the load, not the battery. The battery always has a higher potential than the load, The battery charger in this case the PV/CC has the highest potential (so long as we are using a proper charger with the right voltage)

Its just against physics for a battery to draw electricity more than the load. The above is the theory.

For the practical, I have a Victron Battery Monitor BMV 700 the BMV comes with a current shunt which is connected to negative of the battery, inverter DC input negative cable and Controller dc output negative cable. The positive cable of the BVM connects to the battery.

The BMV monitors currents going into and out of the battery from the Inverter and CC. The BMV display shows gross net input and output to the battery hence
1 if my charge controller shows it is producing 24A and my load is 10A, the victron battery monitor shows 14A going into the battery. and this is confirmed by the battery voltage.

If I turn off the 10A load, I see the BMV showing 24A going into the battery. If I turn off the CC, the BMV will show -10A being drawn from the battery.

If my load is say 24A and CC is pulling 20A, the BMV shows -4A leaving the battery.

This idea that all power from the cc first goes to the battery and the load pulls it from the battery is false and against the principle of how electricity works. when I have time over the weekend I will demonstrate the truth of this.

bigrovar:


This assumption is wrong in theory and in practise. Electricity flows from high potential to low potential.

Scenario 1 If say your PV is producing 1000w and your load is using 1200w, 1000w goes from your CC to your load, and the reminder 200w is taken from the battery.

Scenario 2 If your battery is full and your PV can potentially produce 1000w and your load is 1000w, the load from the PV goes straight to the inverter (Your battery is completely ignored.)

Scenario 3 If your PV can potentially produce 1000w and your load is using 500w then 500w goes from PV to load and unused 500wh would become potentials.

Scenario 4 if your battery is low and your PV is producing 800w but your load is using 800w,all 800w produced by the PV goes to the load. Non is left for the battery.

Remember like I said, electricity moves from high potential to low potential.. The lowest potential in all the above scenario is the load, not the battery. The battery always has a higher potential than the load, The battery charger in this case the PV/CC has the highest potential (so long as we are using a proper charger with the right voltage)

Its just against physics for a battery to draw electricity more than the load. The above is the theory.

For the practical, I have a Victron Battery Monitor BMV 700 the BMV comes with a current shunt which is connected to negative of the battery, inverter DC input negative cable and Controller dc output negative cable. The positive cable of the BVM connects to the battery.

The BMV monitors currents going into and out of the battery from the Inverter and CC. The BMV display shows gross net input and output to the battery hence
1 if my charge controller shows it is producing 24A and my load is 10A, the victron battery monitor shows 14A going into the battery. and this is confirmed by the battery voltage.

If I turn off the 10A load, I see the BMV showing 24A going into the battery. If I turn off the CC, the BMV will show -10A being drawn from the battery.

If my load is say 24A and CC is pulling 20A, the BMV shows -4A leaving the battery.

This idea that all power from the cc first goes to the battery and the load pulls it from the battery is false and against the principle of how electricity works. when I have time over the weekend I will demonstrate the truth of this.

makavele:
Let me correct a misconception here . . .
Take for example a 40A mppt controller on a 600W array connected to just a single 12V 100Ah battery
On a very good day, during bulk charging the array is capable of pushing out 25-30 Amps
But we all know it is best to charge batteries at one-tenth capacity (C10) i.e. in this example 10A;
So your controller is pushing 30A, which is an overkill for the battery.
Most people, like the poster above me, believe you can add or turn on some load to reduce the current entering the battery.
This is a misconception and why is so?

[b]1. The PV array does not directly power any load connected to the inverter/battery bank.

2. What happens is that the battery is discharging and charging at the same time albeit very fast.
3. If for example, the total load turned on is 100W; and the PV is producing 150W; what happens is that the load
will draw 100W from the battery (discharge); and at the same time the PV will pump in 100W (recharge) to the battery
to replace what is lost and 50W is used to keep the battery in float (if it is already in float);
or used to keep charging the battery if it isn't yet in float

SO back to our example, what if the CC is delivering 30A on a c10 rated battery . .
if you like turn on all the load in the world; what is happening is that . . the CC is still sending in 30A to your battery
and in turn your battery is powering the loads connected, be it 10A, 20A, 2A, 100A
If the CC amp is greater than the load, the battery stays charged up
if the load amps is greater than CC amp, the battery will start discharging even while being connected to solar.

Thanks

Chuckdee:







The bolded is soo wrong and misleading. Please how do you then explain how people in advanced countries like US and Europe that are on reliable grid that almost never goes down but have Solar setups without a single battery bank and yet make use of energy generated by those panels??... lets not BOLDLY mislead newbies that come to this thread to learn