Solar DC as driver input

Rocket Soul

Well-Known Member
Basicly im trying to figure out if i can use the DC - current from an array of solar panels to power a led driver. Normally a solar installation has batteries and an inverter to transform the power to AC. As led already runs on DC i wanna bypass batteries and inverter to power the driver directly. Im hoping to gain some power during daylight hours to mask my power signature from the power company.

Has anyone tried this? Or know of anything to read up on it?

If i understand correctly you get a fairly constant voltage from the panels, either 12,24 or 48V. And then the current will adjust according to how much sun hits the panels.

My first idea is LDDs, but i dont know how they would react when the current from the panels go real low or high. Anyone know how this works?
 

Moflow

Well-Known Member
Basicly im trying to figure out if i can use the DC - current from an array of solar panels to power a led driver. Normally a solar installation has batteries and an inverter to transform the power to AC. As led already runs on DC i wanna bypass batteries and inverter to power the driver directly. Im hoping to gain some power during daylight hours to mask my power signature from the power company.

Has anyone tried this? Or know of anything to read up on it?

If i understand correctly you get a fairly constant voltage from the panels, either 12,24 or 48V. And then the current will adjust according to how much sun hits the panels.

My first idea is LDDs, but i dont know how they would react when the current from the panels go real low or high. Anyone know how this works?
Probably not much use?
Was lying in the garage. Used it on batteries.
20190513_170335.jpg
 

PSUAGRO.

Well-Known Member
Yes, as air stated, their was a in-depth thread about this.......the electrical engineer who just recently passed away sadly, forget his name now?, talked about it's flaws for a dc source . He had extensive experience with wind farms or something of that nature...

Sorry rocket, can't help more than that .
 

Rocket Soul

Well-Known Member
Yes! That's who clarified the hurdles in using solar for powering led lights.....
Thx P, noone remembers where this was talked about? Ive found a few threads talking abiut this, or about a full solar installation with batteries but nobody actually doing it.

What i would really like to find out:
Does anyone know what happens if i over or under power a ldd driver using solar panels?
 

1212ham

Well-Known Member
Basicly im trying to figure out if i can use the DC - current from an array of solar panels to power a led driver. Normally a solar installation has batteries and an inverter to transform the power to AC. As led already runs on DC i wanna bypass batteries and inverter to power the driver directly. Im hoping to gain some power during daylight hours to mask my power signature from the power company.

Has anyone tried this? Or know of anything to read up on it?

If i understand correctly you get a fairly constant voltage from the panels, either 12,24 or 48V. And then the current will adjust according to how much sun hits the panels.

My first idea is LDDs, but i dont know how they would react when the current from the panels go real low or high. Anyone know how this works?
I posted a little about it once, try searching solar and my username. A panels voltage will vary with the amount of light and the load. In a normal system, a charge controller is used between the panels and battery bank. A 12v panel actually has max efficiency around 18-20v, a charge controller uses pulse width modulation to regulate charging voltage.

I have an idea to connect panels directly, the trick is careful matching of panel voltage and power capability to the LED. When the sun is weak, a Meanwell could supplement the power. I'll post more tonight.
 

Rocket Soul

Well-Known Member
The idea is that the meanwell LDD acts like the regulator between panels and leds.

I wouldnt be using only solar, i i wou have the space minimally lit by mains power. The idea is to use the solar for some red flower boosters that wont turn up on our power consumption.
 

Dodgey99

Well-Known Member
Solar regulators are designed to charge batteries on their output, so they simply must be plugged into batteries for them to work. They are assessing the "battery" voltage on the output, to then decide what voltage to push out as a charge , how much current, and what stage - e.g. Bulk, Equalise, maintenance/trickle etc. If they see no voltage they won't try and charge.

On top of this, solar regulators are powered by the batteries they are connected to, NOT the solar panels. Most solar regulators I work with will power down when you disconnect the battery, even in good sun.

Almost all regulators have a "load" output - which is NOT a charging output. It is clean simple 12 or 24v. However, this load port depends on taking this power from the battery it is supposed to also be connected to, via the battery port.

Without a battery solar regulators don't work.

If you bypass / don't use a solar regulator, the panel outputs around 20v, with amps depending on sunlight and temperature.

Whatever device you feed this power into, has to be able to deal with a swing of 12 -20v (or 0v at night) and a current range depending on your panel array size. To give you an example, a 100w 12v (20v really) panel will kick out anwhere up to 6 amps. To power a 300w LED light you will need at LEAST 4 x 100W panels, kicking out up to 24 amps. A very quick and dirtly look at LDD LED drivers by meanwell showed me them maxing out at 2.8 amps.

You really, really need to use batteries as a buffer. At high wattages, you'll need a lot of batteries.
 

1212ham

Well-Known Member
The idea is that the meanwell LDD acts like the regulator between panels and leds.

I wouldnt be using only solar, i i wou have the space minimally lit by mains power. The idea is to use the solar for some red flower boosters that wont turn up on our power consumption.
What is the voltage and power of the LEDs you want to drive? I doubt LDDs would work, but I have some ideas.
 

Airwalker16

Well-Known Member
you usually link to said discussion when trying to be a smart ass.
I'm really over your bullshit attempts to call out anything you see fit whe I post. Just stop quoting my posts and leave me alone please? Otherwise I'll just ignore you and unlikely, miss a gem you might post in the future.
 

Rocket Soul

Well-Known Member
What is the voltage and power of the LEDs you want to drive? I doubt LDDs would work, but I have some ideas.
Id adapt the solar/driver/leds custom.

Basicly the idea is to run a low power setup all day long and use the generated power from the panels as a flower boost of red leaning spectrum. Maybe reds on strips or low driven low CCT boards or strips.
Most strip options ive looked at are around 24 V, at least at the currents i wanna run.

Im just looking for how i could attach some drivers to the solar output. I thought of ldds as they are efficient from dc. Also hoping they can be attached directly to DC but not sure exactly how they would work when im in low power from the panels.

@Airwalker16 @sethimus
When you take your personal drama to a thread thats just been started you greatly increase the chance that people who actually have an interest or knowledge wont post, due to drama, which is an disservice to the thread.

Im pretty sure the knowledge to how to do this is on the forum. Does anyone know how current and voltage varies in low light settings? Does anyone know how ldds would act if under driven?
 
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Rocket Soul

Well-Known Member
Solar regulators are designed to charge batteries on their output, so they simply must be plugged into batteries for them to work. They are assessing the "battery" voltage on the output, to then decide what voltage to push out as a charge , how much current, and what stage - e.g. Bulk, Equalise, maintenance/trickle etc. If they see no voltage they won't try and charge.

On top of this, solar regulators are powered by the batteries they are connected to, NOT the solar panels. Most solar regulators I work with will power down when you disconnect the battery, even in good sun.

Almost all regulators have a "load" output - which is NOT a charging output. It is clean simple 12 or 24v. However, this load port depends on taking this power from the battery it is supposed to also be connected to, via the battery port.

Without a battery solar regulators don't work.

If you bypass / don't use a solar regulator, the panel outputs around 20v, with amps depending on sunlight and temperature.

Whatever device you feed this power into, has to be able to deal with a swing of 12 -20v (or 0v at night) and a current range depending on your panel array size. To give you an example, a 100w 12v (20v really) panel will kick out anwhere up to 6 amps. To power a 300w LED light you will need at LEAST 4 x 100W panels, kicking out up to 24 amps. A very quick and dirtly look at LDD LED drivers by meanwell showed me them maxing out at 2.8 amps.

You really, really need to use batteries as a buffer. At high wattages, you'll need a lot of batteries.
I wouldnt use one ldd driver to drive 300w. Just like you connect an array of ldds to a CV driver the idea is to connect them to your solar output. The ldds then power strips and boards.
 
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