diy solar

diy solar

How's my rig doing?

vatin

New Member
Joined
Jan 12, 2022
Messages
8
Location
Thailand
Hello world of solar power and hello everyone.

I'm a beginner and very non tech incline, stepping into the world of solar power.
I'm here to seek your guidance and recommendations.
My rig consisted of 2 of these PV panels, rated at 150 W each. So 300 W combined.
They are connected to this inexpensive charge controller, rated at 30 A.
I use this rig to charge the 30000 mAh ELOOP (E29) Powerbank via USB cable.
The power bank could be charged fully in about a week.
I only have direct sunlight during the afternoon since the panels are setup vertically in door against my apartment glass window.
During its' peak hours I noticed the charge controller gets a bit hot.
I plan to move the PVs outside soon, but they will have to still be installed vertically at the balcony due to space constraints. I expect the absence of glass window would help increase the charging performance.

My big question here is, considering all the equipment with specifications as detailed. Are they optimal for the use case being mentioned?
Are there any fatal flaws, bottle necks, short comings that could be improved? As an unenlightened, what I see is the rig could charge my power bank fine, and free energy is great. But I still want to know if there's anything I could do to improve?

Thank you so much.
 
Hello world of solar power and hello everyone.

I'm a beginner and very non tech incline, stepping into the world of solar power.
I'm here to seek your guidance and recommendations.
My rig consisted of 2 of these PV panels, rated at 150 W each. So 300 W combined.

First, those panels are NOT 150W.

Panel dimensions are:

.864m * .563m = .486m^2

Under 1000W/m^2 STC, 1000W/m^2 * .486m^2 = 486W (maximum amount of solar power on the panels in perfect condition)

Panels are about 20% efficient:

486W * 20% = 97W - so those are 100W panels at best. They could be as low as 75W.

So, you have a 200W system, not 300W. Furthermore, fl

They are connected to this inexpensive charge controller, rated at 30 A.
I use this rig to charge the 30000 mAh ELOOP (E29) Powerbank via USB cable.
The power bank could be charged fully in about a week.

30000mAh = 30Ah - what voltage?

I only have direct sunlight during the afternoon since the panels are setup vertically in door against my apartment glass window.

You'll be lucky to get 50W total.

During its' peak hours I noticed the charge controller gets a bit hot.
I plan to move the PVs outside soon, but they will have to still be installed vertically at the balcony due to space constraints. I expect the absence of glass window would help increase the charging performance.

Through a window typically cuts available power by 50% or more.

My big question here is, considering all the equipment with specifications as detailed. Are they optimal for the use case being mentioned?

Too little information to answer.

Battery voltage?
Intended use?
Daily power consumption?
etc.

PET panels have poor life. The best flexible panels have an ETFE coating to improve life.
 
First, those panels are NOT 150W.

Panel dimensions are:

.864m * .563m = .486m^2

Under 1000W/m^2 STC, 1000W/m^2 * .486m^2 = 486W (maximum amount of solar power on the panels in perfect condition)

Panels are about 20% efficient:

486W * 20% = 97W - so those are 100W panels at best. They could be as low as 75W.

So, you have a 200W system, not 300W. Furthermore, fl



30000mAh = 30Ah - what voltage?



You'll be lucky to get 50W total.



Through a window typically cuts available power by 50% or more.



Too little information to answer.

Battery voltage?
Intended use?
Daily power consumption?
etc.

PET panels have poor life. The best flexible panels have an ETFE coating to improve life.

Thanks for pointing some useful facts.
Regarding the power bank being used.

- Capacity: 30000 mAh Li-Polymer battery
- Input (Micro) current: DC 5V - 2A & DC 9V - 2A
- Input (Type - C) current: DC 5V - 3A & DC 9V - 2A (PD + QC 3.0)
- Output (Type - C) current: DC 5 - 6V / 3A & DC 6 - 9V / 2A & DC 9 - 12V / 1.5A (PD + QC 3.0)
- Output (USB) current: DC 5 - 6V / 3A & DC 6 - 9V / 2A & DC 9 - 12V / 1.5A (QC 3.0)
- Output (USB) current: DC 5V / 2.4 A

So there are 2 inputs. Micro and Type C. Which is the better choice?
 
So is this a power pack like one might use to recharge a cell phone?

Micro: 10W (5V) or 18W (9V)
C-type: 15W (5V) or 18W (9V)

Is the controller connected to a battery?

What is the USB output of the controller? I see no documentation.
 
So is this a power pack like one might use to recharge a cell phone?

Micro: 10W (5V) or 18W (9V)
C-type: 15W (5V) or 18W (9V)

Is the controller connected to a battery?

What is the USB output of the controller? I see no documentation.
Clicking on one of the thumbnails of the linked charging controller page. The controller outputs 5 V via its USB port.
Yes. The power bank is a portable one designed to charge cell phone or any portable devices.
The controller is connected to the battery. That’s why I could charge it.
 
Clicking on one of the thumbnails of the linked charging controller page. The controller outputs 5 V via its USB port.

5V is the voltage, which is standard for USB. It's output would include either current in Amps or power in Watts. Without Amps or Watts, you can't determine how quickly you can charge.

Yes. The power bank is a portable one designed to charge cell phone or any portable devices.

Okay.

The controller is connected to the battery. That’s why I could charge it.

This is atypical. Most charge controllers MUST be connected to an actual 12/24/48V battery to operate properly. This may be a special situation where the USB works even if not connected to a battery.
 
5V is the voltage, which is standard for USB. It's output would include either current in Amps or power in Watts. Without Amps or Watts, you can't determine how quickly you can charge.
I toggled through the modes and couldn't find Amps or Watts indications. Only Volts, which read 20 when not connected to the said power bank. And drop down to around 6 when connected. My intuition suggest that the dropped volts flows to the power bank.

Okay.



This is atypical. Most charge controllers MUST be connected to an actual 12/24/48V battery to operate properly. This may be a special situation where the USB works even if not connected to a battery.
Well. That's fascinating to know. BTW, I think this is the user manual of the charge controller. If adding the 12V battery could increase the charging performance. It's worth the small additional investment.
 
I've connected a small 5amps 12 volts battery to my rig, and my power bank could be charged noticeably faster.
I guess that this is how it is suppose to work.
I could reach above half capacity of my 30,000 mil amp power bank in about 2.5 days, which is quite faster than prior to adding the 12v battery.
 
*Bump*

The 12 volts 5 amps battery I'm referring to is a motorcycle battery. Is this suitable for solar power storage? Currently I have to drain the power to my 30,000 amp powerbank several times in order to fully charge the powerbank. Which takes about a little over a week.
 
If you can get those panels outside you'll fill your pocket battery MUCH faster.
That window is killing your system. Residential windows are designed to block the UV light that panels love so much.
Any battery is better than no battery.
Many of the cheaper PWM controllers will still charge through the USB port even without a battery. Not uncommon at all, but not necessarily healthy.
Assuming the USB port is bog standard 5v@250ma it's going to take FOREVER to charge that bank. If there's a local auto parts store around, go get a 12v USB charger socket or even better, if they have it, a USB-C quick charger. Connect it right to the battery (through it's inline fuse) and watch your power bank fill up in a few hours.
 
@Rednecktek First of all. Thank you so much for spending time going thought the entire threat, and bare with my newbie question.

If you can get those panels outside you'll fill your pocket battery MUCH faster.
That window is killing your system. Residential windows are designed to block the UV light that panels love so much.

I've move my entire setup to my apartment's balcony out door for some time now. I have no scientific proof but it didn't feel much improved.

Any battery is better than no battery.
Many of the cheaper PWM controllers will still charge through the USB port even without a battery. Not uncommon at all, but not necessarily healthy.
Assuming the USB port is bog standard 5v@250ma it's going to take FOREVER to charge that bank. If there's a local auto parts store around, go get a 12v USB charger socket or even better, if they have it, a USB-C quick charger. Connect it right to the battery (through it's inline fuse) and watch your power bank fill up in a few hours.
Thank you for your suggestion. But I don't think it matters much to me. Since when I connect the powerbank to the USB, the controller will drain the charge "from" the 12V battery "into" the powerbank anyway, and also supplemented with real time charging from the sun, if there is sunlight. So as long as the 12V battery can be charged at typical speed I'm OK with that.
I'm more concern with how to maximize the power from the sun "into" the battery.
The powerbank could drain the 12V 5AH battery rather fast, which is very much acceptable. Maybe switch to a larger capacity 12V battery might be more useful....

To put it simply, the bottle neck in my rig is the solar charging capacity. Not between the 12V battery and the power bank.
So it does't warrant to increase the charging rate between these two. Because my solar cell is FAR FAR too small to cause a bottle neck. A humble USB charging rate of 5V@250ma is more than enough to quickly drain the 12V battery in no time. No point to speed this up.
 
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First, those panels are NOT 150W.

Panel dimensions are:

.864m * .563m = .486m^2

Under 1000W/m^2 STC, 1000W/m^2 * .486m^2 = 486W (maximum amount of solar power on the panels in perfect condition)

Panels are about 20% efficient:

486W * 20% = 97W - so those are 100W panels at best. They could be as low as 75W.

So, you have a 200W system, not 300W. Furthermore, fl



30000mAh = 30Ah - what voltage?



You'll be lucky to get 50W total.



Through a window typically cuts available power by 50% or more.



Too little information to answer.

Battery voltage?
Intended use?
Daily power consumption?
etc.

PET panels have poor life. The best flexible panels have an ETFE coating to improve life.
Yep. I just bought a couple of "100 watt" panels from Amazon. When I got them and saw how small they were, I knew immediately that the were 70-80 watt panels. High efficiency, for sure, but not 100watt. But since they are providing power for a 500wH portable power station, they are still suitable and might even be easier to transport. My point is, we have to start paying attention to the physical size of the panel because the description of the panel is lying.
 
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Further question. I got myself a 12V USB quick charger, the one for use in the automobiles.
Question is, can I wire them directly to one of the terminals of the charge controller?
If so, which terminal should I wire it to A (Battery charging terminal) or B (Output load terminal)? Please see the picture below.
Screenshot 2565-12-21 at 18.46.16.png

My intention is to charge my 30k ah power bank using this 12V USB quick charger. Without the hassle of having to connect an extra 12V battery.
I want my 30k ah power bank to be my only power storage for my entire solar charging rig. I have 2 of these power bank and simply switch it out for use. While the other is charging.
 
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