System design

[Diallodjeri]

Hello folks,


I have a few questions about my system design.

I want to set up a system in region where there is an abundant sunlight throughout the year, precisely in west Africa. I might just not have enough storage to harness all that beautiful sunlight in order to power all my appliances at night, may be just enough storage to power the essential appliances at night.

I'm planning on buying 21 pannels of 265 Watts each which should give me around 5kwh in shining day. I want to set it up in way so I can power all my appliances and and fully charge my battery during the day when there is plenty of sunshine. I have SimpliPhi PHI 3.4kWh(Lithium Ferro Phosphate) which is big enough to only power my essential appliances at night, but not the whole house.

I want to set it up in way so my appliances will draw a power from only the panels not the battery during the day when there is plenty of sunlight. At night the battery, which has not been used during the day, will be used to power only my essential appliances.
I want to make sure I'm not doing anything to will negatively impact the life cycle of my battery because I want to be able to use that battery as long as possible.

I was told that I can use 21 panels in string of 3 panels with 2 charge controllers of Outback 80 Amp 12/24/48/60 Volt Flexmax 80 MPPT Charge Controller and 1 Outback Radian 3500 Watt 48VDC Inverter / Charger.
Or I can use 18 panels in string of 3 with 1 charge controller, but the charge controller will be running at full capacity at all time, which is not really recommend.

I really would like to how I can accomplish this goal.

Allright folks, I was finally able to post my entire text and I would appreciate any help.

[B]I

[Mike90250]

The more batteries you have to run things all night, the more solar PV panels are needed to keep the batteries at a healthy charge. What are your questions ?

[Diallodjeri]

The site is not letting me post my whole text, it's cutting my post off and I have no idea why.

[littleharbor]

Are you posting links other websites? These generally need to be approved by admin.

[SunEagle]

The site is not letting me post my whole text, it's cutting my post off and I have no idea why.

The software also limits most cutting and pasting. While it may take longer I would suggest you type out the specifics of your needs and questions. You can then edit your post if needed.

Oh. Welcome to Solar Panel Talk.

[Diallodjeri]

That's the issue because I was trying to copy and paste the whole text. I guess I'm going to have to type the whole text tonight.

Thanks.

[max2k]

That's the issue because I was trying to copy and paste the whole text. I guess I'm going to have to type the whole text tonight.

Thanks.

you probably can paste your text to some 'dumb' text editor first which doesn't support any text formatting and then copy it from there to the site. The first step would get rid of the all the formatting leaving just pure text. I use TextPad for this but I'm sure there are others as well and if you're on Windows you can try to use Notepad for this.

[sensij]

you probably can paste your text to some 'dumb' text editor first which doesn't support any text formatting and then copy it from there to the site. The first step would get rid of the all the formatting leaving just pure text. I use TextPad for this but I'm sure there are others as well and if you're on Windows you can try to use Notepad for this.

I think he figured it out, the first post was edited with the full text now showing. Yet another person who wants to undersize a battery because they think they can manage daytime loads manually.

[SunEagle]

I think he figured it out, the first post was edited with the full text now showing. Yet another person who wants to undersize a battery because they think they can manage daytime loads manually.

Sure you can manage your daytime loads. It just takes total attention to do it manually or install a $10k control system that will shed loads depending on how much is being generated by the solar panels. It just requires contactors, circuit breakers and a PLC to control the whole thing. Piece of cake.

[Diallodjeri]

I often heard people talking about programing the inverter, for intense the Outback Radian GS3548E. I was wondering what kind of programming you can do with that piece of equipment.

[NEOH]

Hello folks,

I have a few questions about my system design.

I want to set up a system in region where there is an abundant sunlight throughout the year, precisely in west Africa. I might just not have enough storage to harness all that beautiful sunlight in order to power all my appliances at night, may be just enough storage to power the essential appliances at night.[

I'm planning on buying 21 panels of 265 Watts each which should give me around 5kwh in shining day. I want to set it up in way so I can power all my appliances and and fully charge my battery during the day when there is plenty of sunshine. I have SimpliPhi PHI 3.4kWh(Lithium Ferro Phosphate) which is big enough to only power my essential appliances at night, but not the whole house.

I want to set it up in way so my appliances will draw a power from only the panels not the battery during the day when there is plenty of sunlight. At night the battery, which has not been used during the day, will be used to power only my essential appliances.
I want to make sure I'm not doing anything to will negatively impact the life cycle of my battery because I want to be able to use that battery as long as possible.

I was told that I can use 21 panels in string of 3 panels with 2 charge controllers of Outback 80 Amp 12/24/48/60 Volt Flexmax 80 MPPT Charge Controller and 1 Outback Radian 3500 Watt 48VDC Inverter / Charger.
Or I can use 18 panels in string of 3 with 1 charge controller, but the charge controller will be running at full capacity at all time, which is not really recommend.

I really would like to how I can accomplish this goal.

Allright folks, I was finally able to post my entire text and I would appreciate any help.

First => You said ...
I'm planning on buying 21 panels of 265 Watts each which should give me around 5kwh in shining day.
I think you meant 5,000 watts, not 5,000 watt-hours - right?

I think the calculation is more like ...
30,600 Watt-Hours = 21 Panels x 265 Watts x 5.5 Solar Equiv Hours.

30 KWH per day certainly is enough energy to run an "average" home.
But you never specified how many KWH's your home will consume during the day or during the night.

a) 15 KWH during the day and 15 KWH during the night ???
b) 20 KWH during the day and 10 KWH during the night ???
b) 25 KWH during the day and 05 KWH during the night ???

During the day, you have plenty of PV Power.
During the night ( from sundown to sunrise) that little 3.4 KWH battery bank is severely undersized

3.4 KWH = 70AH x 48 Volts

Is this a Grid-Tie, Off-Grid or Hybrid design?
If you have Grid then why do you need a Battery Bank?

[Diallodjeri]

I don't have a hard number of my consumption yet, but I think is going to be 2 mini split AC, where one is 1350 watts and the other is 580 watts plus one refrigerator and one freezer. These are the appliances that will be running off the battery at night. The system is a complete off-grid.

[SunEagle]

I don't have a hard number of my consumption yet, but I think is going to be 2 mini split AC, where one is 1350 watts and the other is 580 watts plus one refrigerator and one freezer. These are the appliances that will be running off the battery at night. The system is a complete off-grid.

Without doing some work to determine approximately what your daily watt hour usage will be there is no good way to determine what type of solar/battery system you need to design.

Knowing the wattage of your loads is a starting point but then you need to estimate how many hours a day they will be running at that wattage.

[Diallodjeri]

Hi folks,

I'm really glad I can come to you guys with my solar energy questions.

I want to learn as much as possible before I can start spending my money with confidence.


My daily consumption should be around 3.5 kWh and the night consumption should be around 1.5 kWh to 2 kWh, but I'm buying enough panels that can generate at least 5 kWh which should be enough to charge my battery and satisfy my load at the same time during a day.


I want to know if I should still be concerned about having a too small battery for too big panels as long as I have a good charge controller seating between my panels and the battery.

If I understand the design, the charge controller should be protecting my battery from over charging as well as from over discharging. I can see how the over charging mechanism would work because the charge controller is seating between the panels and the battery. I just don't understand how the mechanism against over discharging would work though.


I was looking to buy (2) SimpliPhi 3.4 kw, 24v battery which would give me a combine storage of 6.8 kw for almost $7000, but I have seen some used forklift battery online with similar capacity for half of this price. I don't know much about a used forklift battery other than it's not sexy, it's bulky and heavy, but I'm willing to sacrifice the sexiness for efficiency. Does anyone knows about a forklift's lithium ion battery. Is that battery a good investment?

Whatever battery I'm going to go to buy has to be a lithium ion battery because of its safe technology.


I just want a system with a good critical components such as panels, charge controller, inverter and battery; I don't need all those belts and whistles like communication hub, remote control feature, or any other extra fancy feature, but I do really want a good reliability plus a basic monitoring of the system to see if everything is working like they supposed to. In order to accomplish that, what sort of basic monitoring device do I need?.

[Diallodjeri]

Any suggestion?