₦airaland Forum

I have heard. Solar does not work when it rains or when it is cloudy

This is a question we get asked every time. Will solar work during the rainy season? Will solar work when it rains.
The answer is yes. Your panels will still produce power even though the production is diminished. This is when a really good charge controller is worth its weight in Gold


https://www.youtube.com/watch?v=w7C1Fj6EjZs

richmon74:
Try Solrworld Solar panels. I have seen 17.4kWh/D from a 3.06kw Solarworld Submodule Mono Panels.
The figure does not depend on the solar panel quality only. It depends also on load and installation.

I have used Solarworld panels for my clients. I get 4.9 kw/h on a good day (load dependent) on my 1 kw in Renesola panels. I have seen them produce as much as 900 Watts. Thank you for the tip. (The load in the house is limited to a refrigerator, a desktop and fans)

adanny01:
Sorry for asking too much.

I went ahead to do further research online, found an AGM battery 12V 200AH which tech specs mentioned recommended maximum charging current limit as 60A.

This answers my question. Thanks so much.

I like that you took the time to answer your own question. No apologies necessary.

adanny01:
Welcome.

1 more question. Isnt 40A too much for a 200AH or to put in another way , is there a limit of charging current for a particular battery capacity? Example, would a 100A charger be too much for a 100AH battery.

Your question quota don finish. Now I go begin charge. Read my prior response again and you can guess at the answer.

kozmokaz:
lol.... daz not wat i meant dude.... ok let me explain it dis way.... gt a generator coil(dynamo) .... u know it s d turnin of d coil dat generate d electricity....2: fix d coil head to a source dat rotates .(strong refridgerator motor) wen connected to a power source (battery) ... wen u power on d motor, as d motor rotates, it in turn rotate d coil which den produces electricity ... u can also charge ur ba3 from d electricity produced... ther are oda equipments to add buh d major ones are d coil(dynamo) .... fan(motor head) and ur ba3 .... dis was my final year in sec sch practical tho... u can as well add ur own to mak it more dope

Thank you for taking time to explain your high school project to us. Now can you tie it to solar and how we can benefit from it.

JUO:
and that doesn't come cheap, since MorningStar has 600v input are you saying one should put 550v or 600v since the the cc can handle 600v? High dc voltage can kill incase we have forgotten

DC voltage over 80 is dangerous ( can stop your heart). That high will kill. Grid tied inverters run voltages that are that high. Someone mentioned that the max for charge controllers was 150.
You know know it is not. And no I don't advocate going to the max pv voltage. There are phenomenon that will make your PV spike beyond the installed voltage.

adanny01:
I guess you are well learned or experience on these systems.

I wish to ask question as i have limited knowledge.

Assume having a standard inverter that has a charger with batteries installed. If i wish to add a solar charger to the system i know it requires a charge controller. I do understand that the charge controller as well as the inverter must be connected directly to the battery. Both the charge controller and the inverter monitor the battery voltage the charge as appropriate.

My main question is that, is it safe for the battery that 2 chargers oblivious to one another are charging at the same time even though both know the actual level of charge the battery holds.

This is because if the inverter charger is 20A and the charge controller is also 20A and both see that the battery needs charge. The inverter charging at 20A and solar at 20A for a 200AH, isnt that bad. How can this be rectified.

Thank you for the compliment.

I will answer your question while adding some extra.

1. The AC charger stops charging once the batteries reach a predetermined voltage and it has gone through a programmed routine. Your 20A will take 10 hours to charge your 200 AH battery.
2, The charge controller follows the same routine as the AC charger. It stops charging when the battery is fully charged.
3. Combined they (AC charger and controller) can produce up to 40 amps, charging your 200 AH in 5 hours.

Look at the picture below. The AC charger had fully charged the batteries, the controller was only along for the ride

kozmokaz:
same principle used in dams wen explain better

So you are saying that I am going to remove the charger / alternator / dynamo from a car and take it to a dam and then what do I do?
You can expand on your subject further. People are really interested in a means of generating power that does not involve fossil fuels. Please explain yourself better.

abunafiu:
Oga juo... don't mind me. I felt the need to let people know that 3 by 3 is not harmful to mppt controller.
To be honest, if u refer to the manual that came with the TSMPPT60 ..3 by 3 is discouraged. Sometimes in 2013., my self, GeorgeD1 and some other guys discussed this extensively. After practicals , we concluded 3 by 3 was the best for 48v systems.
When I tried the same for 24v, I discovered I was loosing power but my cc worked fine for almost a month when I 4kw inverter was away. I use only 1080watts in total.

As u rightly pointed. high voc will fry pwm easily. voc above 150v is strongly discouraged for mppt cc.

Happy sunday bro!.

Mornigstar has a 600 V MPPT and Midnite Solar has a 250 V unit. Most controllers have a 150 V max. The Chinese have as low as 70 V and can max out at 145 Volts.
Having the recipe does not make one a chef. That is why forums like this are a gold mine.

durodee:
Update on thin film panels 1.4kw on 60 amp MPPT iTracer . Got a total harvest of 8.1kw yesterday. Pic taken around 5pm when harvest was 8kw. Fingers crossed!!!

This is beastly. Bro that number is sick. I need 2 kw in poly to get your numbers. You are getting performance that is out of this world. I will try them eventually.

I have heard that PWM controllers work very well on huge installations.

This is a correct statement. As long as you can afford to buy the panels a PWM will do the job.
An MPPT allows you to extract more from your installed PV using some proprietary algorithm. You can see a harvest of up to 30% more than you would from an MPPT.
If you can afford it buy an MPPT controller. Never skimp on quality. It will make a difference in the long run.


https://www.youtube.com/watch?v=DrB5DktczDY

c0ogumo:
The Voc of Renogy is 37.5V x 4pcs =150Vdc
Maybe the the panels produced more power than what the CC can handle over a long period
Try to use 2 x 2 configuration next time since you have a 24V system.

Regarding the 130% comment. I think they meant watts not volts. In Nigeria I have seen funky stuff from our solar installation. Cables from controllers getting hot, fans running all the time, 1 kw in panels producing 980 W at the controller.
You have to allow room in your design for stuff like that.

GreenCashServic:
Thanks a lot for ur prompt and educative response. I may have 2 last questions for now. The first being that considering the fact that these batteries are no longer useful to me as I have already given up on them, can they be added to one regular 12 volt battery recommended for the system? Secondly, how much can I get a good charge controller for the solar connection and where?

It was my pleasure.
1. I would not mix and match batteries. If you want to use your car batteries keep them the same.
2. So many people on the forum sell good quality controllers. Spend a bit more now and save on your batteries later.

We have seen 3 kw in panels with a 20 amp controller

How do we determine the controller size and the time it takes to charge your batteries?

1. How do you size the controller to match your PV?

There is a formula. We see people put a 40 amp charge controller on 3000 kw in panels on a 12, 24 or 48 V system. This would never work. We have also seen 20 amp charge controllers try to charge 600 AH battery banks.

We will do the easy one first. 600 ah / 20 amps = 30 hrs. A 20 amp charger will take 30 hours (more than a full day) to charge a fully depleted 600 AH battery bank This assumes that there is no load (your inverter or anything else) attached to the battery and there is full sunshine on your panels. So we all agree that a 20 amp charger will never work.

2. How do you match the appropriate controller to the panels capacity you have installed?

Watts / Volts = amps. So if we have 3000 watts in panels and our system is 24 Volts then 3000 / 24 = 125. You need a 125 amp charge controller.
There is are no 125 amp controllers for solar today. So what you do is purchase one 80 and one 60 watt controller. In a pinch I would use two 60 watt controllers. There is a way around this. But it is a discussion for another day.
Having the recipe does not make you a chef.
Have a good day.


https://www.youtube.com/watch?v=0KlDnuUhpp4

martinz1:
this inverter is not good for usage with fan
, it causes the fan to produce abnormal noise
.im actually talking based on previous experience with it

If the inverter is a modified sine wave device it might eventually damage the fan. If the fan does not make noise with the grid, I would disconnect it from the inverter.

GreenCashServic:
Please I have a question too. I intend buying the mercury 2.4kva inverter. I would love to know if it can be connected to a solar panel as well as to the PhCN/ Generator power out put to charge the batteries. Secondly, I have got like 4 car battery's I replaced a while ago...can they come in handy too? Thanks in anticipation

Very good questions.
1. You will need panels and a charge controller to accomplish that task. Yes it can be connected
2. Car batteries are designed for cranking amps or sudden short bursts of power. Your application requires batteries that can tolerate a sustained draw. You will damage the car batteries eventually if you use them in this manner.
Good luck

earthrealm:
sad news...my morning star 45amp CC has died....my folks in the village hv been complaining that the inverter barely lasts 10mins for a couple of days now...was finally able to go check it, thinking twas the heavy rains or something...but alas in bright sunlight the CC was displaying 0amp,i checked the log and this zero harvest started 10days ago....they reported no ligtening strike...so am rally at loss what might hv damaged it......has anyone experienced this b4?...and any luck in repairing it?
the unit is about 21 months old. 4 x 250w 24v renogy panels connected in series. input voltage usually hovers around 130v.
system is hooked up to 2 x 200amphr luminous batts, and 1.5kva 24v luminous inverter....

any suggestions would be welcome,

I am playing taps. What did the manual say the input voltage should be? In Nigeria they will repair anything. Disconnect it and check all your connections. Reconnect.
Sorry for your loss

I have heard you can't run AC on Solar

This is also incorrect. Air conditioners draw a large amount of power over a long constant period. Due to the poor level of insulation of most Nigerian homes, AC run constantly at peak. They struggle to bring the room to the lowest temperature setting that most people leave them on. Hence the draw for extended periods.

If the client wants AC and is willing to pay for it, AC is a worthwhile option that solar will gladly provide. Your pure sine wave inverter produces a constant voltage that is right in the range that AC's enjoy, allowing for the motors to run cooler and more efficiently. Yes AC can be run on solar and in the western world they do.

Watch my video addressing two of the topics. Inverters that catch on fire and batteries that don't last


https://www.youtube.com/watch?v=HDdNu57M_cI

kozmokaz:
car ba3s are charged by dynamos in d engine... rememeber d car engine can also b used to generate electricity

Please explain the principle by which this can be done and how we can use it to charge batteries without burning fossil fuels.

Pharyn:
This is the image of the installation.

Good choice of batteries.

1. Change the cables. They need to be thicker. (depending on the voltage 35 MM is the minimum). I use 50 MM minimum
2. Get a new inverter or an AC charger
3. Check the specific gravity of each cell
4. Charge them fully. ( your charger has to be able to go through a bulk absorb and float ). Set the bulk at 29.6
5. Run an equalization charge at 31 Volts for 1 hour.

This should bring them back if they are not too badly gone.
You might have to repeat this many times during the week to recover the batteries. They are tough batteries and can take the abuse.
Good luck.
This is what happens when you get a quote and then ask someone to beat it and install the same equipment.

That is what we say to a lot of people that get quotes from us. Having the recipe does not make you a chef or a good cook.

HAPPY INDEPENDENCE day my Nairaland pals

Another one. We don't need a charge controller.We connect the panels directly to the battery

What does a charge controller do? It regulates the charge from the panels into the batteries. It acts like a switch that turns on and off to make sure the batteries are not overcharged. Two ways to ruin your batteries over charging and under charging. Over charging dries out your batteries. (Your dry cell has electrolyte.) And once the lead plates are exposed good by batteries. Under charging, you controller can't really stop that if it does not get enough from the panels, but your chances are better if you have a controller. It also stops the current from flowing back to the batteries at night.
Can you plug your panels to your batteries? Yes you can. Is it a good idea? No. So when someone tells you to connect the batteries directly to your panels tell them to keep moving.
Yesterday was a busy day so I did not post this.
HAPPY INDEPENDENCE DAY NAIRALANDERS.

sathob:
Well, great people of FTA, I think I should start this on behalf of George_D because of the request made by others who have expressed interest in alternate electricity, especially solar energy. Our FTA independence is not complete if we are to suffer frequent power outages and been dependant on the nation’s electricity grid system always. I have read in this house many times, from members “PHCN don go off, so I will track later when they come back”. No one can run away from power outages in the main electricity grid – not even the west, it happens. Hence, we all should have alternate electricity and using renewable energy is, to me, the best. This means one can enjoy their FTA fully by being totally free and not “dom” (dominated).

Look at some advantages
• Lower or no electricity bills
• Compared to generator users, there is no fuel cost and stress of getting it and no fumes.
• People living in the remote locations where power is unavailable or too expensive to hook-up too can have electricity.
Just to mention but a few.

Without going into detail, one can enjoy electricity by means of using solar energy (energy from the sun), wind mill (using energy from the wind). Don’t forget, where there is frequent electricity supply from the utility company, you can store some energy for back up.

You will need the following to complete a solar project or back up.

1. Solar panels
2. Power Inverter
3. Charge controller
4. Batteries to store energy
5. wires and cables
6. Monitors/meters

The solar panel consists of cells called photo voltaic cells and these, covert the energy received from the sun to electricity in simple terms (this electricity is a direct current
d.c). The panels can last up to 20 years plus. The panels can be fixed, adjustable or of the tracking type. You can decide to go for a complete panel from manufacturers (already made) or build panels by yourself using solar cells- the latter is for the hobbyist. The panels are rated in watts eg 80w solar panel supplying 12v continuous at a given time

The inverter
Power Inverters are available in 3 basic designs, two of which I remember very well now – the one that out sinusoidal waves and those that are modified sign wave type (meaning not pure sine waves and do have limits when it comes to its application) . The power inverter converts your storage battery power into the 240 volts AC that runs your appliances. It is the heart of your solar energy system. Unless you only run 12 volt DC appliances you will need a power inverter to supply your AC. This is just the basics.

The Charge Controller
A Charge Controller is necessary to protect the batteries from over charging and supply them with the proper amount of energy to promote long battery life.

Batteries
Without Storage Batteries to store energy you would only have power when the sun was shining. There is a lot more to batteries than just the ordinary car battery. Yo may need to change batteries over the years.

Wires and Cables
Without the right size of cables, you are likely to experience inefficient transfer of power (greater losses) and overheating.

Meters
This is required to monitor the performance of your solar system.

Firstly, it is very necessary to know what gadgets you will be using (eg.tv, sat. receiver) and how long you will use how long you would have them on the solar power and how much energy your battery can store and which solar panel (rating in power) will supply the required energy.

A lot goes into calculating the cost of setting up a solar system. First one has to consider the period of usable sunlight available at their location to do this calculation. For us here close to the equator, we get about 7 to 8 hours or more of sunlight during dry season, just a rough estimate.

How do I know I need 100w or 80w or 300 watts solar panel for my project?

The power consumption of appliances is given in Watts. To calculate the energy you will use over time, just multiply the power consumption by the hours of use.

Eg. If I have 90W tv set which I want to use for 6hrs, 25W satellite receiver for the same period, and a 50W fan for 3 hours. What will be the energy required from the solar panels for the period?

1. the energy for each appliance is Watts x time (hours) = Wh

So, the watt hours for the tv = 90 x 6 = 540 Wh (watt hours)

Watt hours for sat. receiver = 25 x 6 = 150 Wh

Watt hours for fan will be = 50 x 3 = 150 Wh

2. sum the watt hours for the individual appliances ie. 540 + 150 + 150 = 840 Wh (watt hours)

This means that the solar panel will need to supply 840 watt hours of energy to the battery each day to cover the total power required by these appliances.

3. since there are bound to be losses in the system However, to account for natural losses, we multiply the result by 1.2 (this factor allows for natural system losses, assuming 85% efficiency). Therefore, we will assume the panels will actually need to be able to supply a total of
840 x 1.2 = 1008Wh

4. so, to supply 1008Wh of energy the panel we assume to receive 7 hours of sunlight will be rated at 1008 Wh / 7 h = 144W
So, I will need 144W solar panel to supply energy to my appliances above at the given time.

Regarding point 3, it also means, if I have a solar panel rated at 100W receiving sunlight for 7 hours a day, the total energy supplied considering 85% efficiency will be 100x7x0.85= 595Wh and not 700Wh

5. Your battery should be able to store 1008Wh of energy. Since batteries capacities are rated in Ah (Ampere Hours) you need to multiply Ah by the Volt rating to know the Watt Hour. Power(W) = Voltage (V) x Current (I) ; Watt hour = VxIxHour

Therefore Ah (which is I x h) = Wh / V = 1008 / 12 (the number 12 represents a 12v battery)
= 84 Ah

So it means you will need not less than a 84Ah, 12V battery (deep-cycle batteries, not ordinary car batteries) to do the job.

NB. Another way of calculating battery capacity is explained in this example. Should my battery be rated at 84Ah, 12V the watt hour (energy) will be 84Ah x 12 V = 1008Ah

It implies that the battery can supply a 150watt appliance for 1008/70 = 14hours

Pls don’t just play around with batteries they are dangerous.

Some corrections.
The panels don't get 7 hours of direct sunshine. That number varies by location. For Lagos the charts say 4.5 on average.
For the batteries. You use the system voltage not the individual battery voltage. If you have a 12 24 or 48 volt inverter you divide by the inverter voltage.
You also need to build in at least one day of autonomy into your system.
And the final and most critical is the size of the battery bank. The minimum size it should be is 2 x your usage. The fastest way to destroy a battery is by completely discharging them and recharging them. Lead acid batteries hate that.
You have given the best explanation for System and battery sizing that I have seen in a while. Keep up the good work

Very exciting topic. It is nice to see people think outside the box. The panels can't make up the structure of the roof. They are not designed as load bearing structures. Solar shingles are more common place. In the United States this works because the shingles sit on a wood board. Nigerians construct roofs differently.
Please keep the conversation going. The reference to the friend in California would work if Nigeria had a feed in tariff and our infrastructure could handle all that extra power going back into it.

I have heard panels are installed facing the east. (hint: the solstices and equinox)

Good morning. More on the myths about solar. The direction you face your panels depends on what hemisphere you live in. For those of us that live near the equator it is not as critical but it helps capture every ray of sunshine. The sun might shine all day but how many hours of direct sunshine do your panels get? It depends on where you live.
If you live in the southern hemisphere you face your panels true North. A couple of reasons. In school they taught you about the summer solstice and the winter equinox. When your days or nights are longer and when the sun is higher or lower in the sky. (remember some people have talked about tilt? that is why). You want your panels positioned in a way that it gets the maximum direct exposure to the sun. (which is about 4 to 5 hours a day). You also want the proper tilt so that it takes advantage of the position of the sun.

Quiz: When during the day are your panels getting the maximum direct exposure to the sun?

JUO:
so that you can use the quote to order the items yourself and look for an installer. Who wants to be used and dumped. Men Don wise. You asked for quote and I believe the make of the items were stated, even. Eg panel sharp 250w, battery Trojan 6v/400ah, inverter prag 48v/6kw. Cc outback 80a. That is not enough for you. You want the street and the country where the items were produced. I believe no one will give you the full spec of the items because that is the secret of any contract.

Bros I gave him a breakdown. Just because one has a recipe does not guarantee a good result. I have no fears. I have had people use my quotes to bid for jobs while others were legitimate buyers. It is part of doing business.

JohnKester:
Thanks for your estimate but must state that a single figure does not suffice. Let's have the breakdown so we can study the individual components.

Cheers.

Click on the link in the email that came with the quote. And you can send a response to the email address that originated the quote.

JohnKester:
I need a 6KW system. The panels, batteries, inverter (PURE SINE WAVE) and the Charge Controller (MPPT) etc, should collectively be sized in terms of capacities and quantities, to form an EFFICIENT 6KW WORKING SYSTEM.

Cheers

Estimate sent

JohnKester:
The system sizing is okay but can be downgraded to between 4 and 5KW.

In the absence of the stated capacities, the available capacities as well as optional capacities can be considered.

Genuine Chinese products can be considered, but not products that were manufactured at the request of some dishonest Nigerians, and which therefore carry the stated capacity on the label but does not deliver the expected performance.

Cheers.

You still are not providing enough information to get a reasonable quote. What appliances do you want to power and for how long? We can calculate battery bank capacity and the PV array size from your response. This will also help determine the charge controller you will need and so much more

I have heard 4 batteries 4 panels

That is a gross misrepresentation. The number of batteries have no bearing on the number of panels.
You could have 4 batteries of varying amp hours. 100 150 200 405 1202 do you still use 4 panels? And what size panels? 80, 100 200 or 250 Watts?
The determinant on the PV size is the watt hours you use and how quickly you need to recharge your batteries. If you have a place that you only use on the weekends, then the PV size will not be as big as a place you use every day.

If anyone tells you that you need to match the number of panels to the number of batteries. Move on to another person.

[quote author=abunafiu post=38415248][/quote]How did you size the system to get the 6 kw inverter? German or American batteries in the Nigerian market come in 2v 6v and 12 V but not in the capacities you list.
The same with the panels. The largest manufacturers of panels are Chinese.