MH vs LED POWER CONSUMPTION

Anemonebuff said:
You could have higher amps, but if the volts are low, you could use less wattage. Our electric bills are billed in watts.
Click to expand...

I assume input voltage will be always 110 or 230VAC. What low input AC are we talking about? If the VAC is constant then the input Amp will determine the power (wattage), PF in AC = 1

This will take a while before I get 50 posts...lol
 
Anemonebuff said:
You are consuming the output volts x amps to equal wattage. Not the input volts x amps.
Click to expand...

Actually, you have to measure the amps in the same circuit as the volts. The amps change from input to output, just like the volts change.

What you are consuming is really the input voltsxamps, because that includes any inefficiencies. What you are charged for by the power company, is most often only the actual or resistive part of that - meaning you have to also multiply by power factor, which finally gives you watts rather than just VA.

However I note some companies are moving to charging for real VA rather than watts,
 
James77 said:
Im sure if they did, it would be to save us money, right? :D
Click to expand...

Of course. It'll make the baddies with poor power factors fix their equipment and so make the power companies more profitable, hence they will pass on the savings to the general consumers - hmm yeah sure :)

Of course there's also the argument that we are saving the planet, and to some extent it's true from the efficiency point of view.
 
Anemonebuff said:
Because you reduce the amount of volts to power the unit. You run 12 LEDs at about 9-10VDC not the full 110VAC coming from the wall. There is some drop off from AC to DC, but that full 110VAC is not being applied.

http://reefledlights.com/how-to-adjust-your-eln-60-48-driver/
Click to expand...

Here is my 2 cents.
The power company will charge you base on the power usage means equal to 110VAC x Amp to turn on the driver and loads (led in this case) x power factor (PF=1) so you will pay the wattage of 110VAC x Amp. Leds will acting like the load, when the load increase the 110VAC Amp will increase and the wattage will increase.

The actual usage power will not accurate if only calculate base on output voltage and output current because some of power loss due to operated all the components inside the driver and output power factor. Low power factor will have less power efficient = more power loss to operate the led.
 
Tenor said:
Here is my 2 cents.
The power company will charge you base on the power usage means equal to 110VAC x Amp to turn on the driver and loads (led in this case) x power factor (PF=1) so you will pay the wattage of 110VAC x Amp. Leds will acting like the load, when the load increase the 110VAC Amp will increase and the wattage will increase.
Click to expand...

Actually you are billed in KWH (killowatt hours) regardless of the differing voltages (your dryer runs on 220V for example) or fluctuating amperages.

Granted there is a mathematical relationship, the end result is the same, because the relationship is proportional. You are billed in KWH.

Tenor said:
The actual usage power will not accurate if only calculate base on output voltage and output current because some of power loss due to operated all the components inside the driver and output power factor. Low power factor will have less power efficient = more power loss to operate the led.
Click to expand...

I don't think that anyone here with knowledge of electrical systems is suggesting you should calculate the actual consumption based on the drivers output. You can always use the datasheet for a particular driver as well to see how efficient it is at energy conversion. According to the Meanwell ELN-60-48D has an 88% typical input efficiency.

Hope this helps,
Landon
 
reefmusic said:
Actually, you have to measure the amps in the same circuit as the volts. The amps change from input to output, just like the volts change.

What you are consuming is really the input voltsxamps, because that includes any inefficiencies. What you are charged for by the power company, is most often only the actual or resistive part of that - meaning you have to also multiply by power factor, which finally gives you watts rather than just VA.

However I note some companies are moving to charging for real VA rather than watts,
Click to expand...

True. The meanwell also cuts the amps down to 700mA.
 
Volt Amps is apparent power - Watts is true power
Great PF is input @ 1 amp with output @.99 amp, this you would see on flourescent ballast. MH are .9 PF, the driver listed on the earlier post was at .64 PF. The only thing worse I have seen are the screw in compact flourescent lamps you buy which are at .5 PF. You measure input watts or amps, not the output watts when it comes to energy usage. Example a 250 watt MH doesn't draw 250 watts, with a PF at .9 it will draw 250/.9 = 277.78 watts or a 80 watt LED with a driver that has a .64 PF - 80 watts/.64 = 125 watts
 
alton said:
Example a 250 watt MH doesn't draw 250 watts, with a PF at .9 it will draw 250/.9 = 277.78 watts or a 80 watt LED with a driver that has a .64 PF - 80 watts/.64 = 125 watts
Click to expand...

Then why are people running the LED driver showing almost 1/4 that wattage draw when measuring with a killawatt meter?
 
From what I have read here from members like BeanAnimal, our electric meters measure watt hours only, and the power compnay takes the hit on power factor.
 
James77 said:
Then why are people running the LED driver showing almost 1/4 that wattage draw when measuring with a killawatt meter?
Click to expand...

What LED Driver? I only gave the one I saw posted very early in this post. If you give me the specifications of a particular driver I can give you the results. With most LED systems you are not going to have a driver that has a PF that poor and most of them are dimmed down, example I have a friend who has the aquailluminations running at only 70% so there is more savings. I think everybody is missing the big point if you have an 80 watt LED light that draws 120 watts but you are replacing 250 watt MH that draws 270 watts then you are saving over 50% on your energy and air conditioning bill.
 
I just went to a website that had dimmable drivers that had a .9 PF. I would suggest if you are doing a DIY LED project that you start with .9 PF driver or better. It read 120v input and 42 volt output max at 700ma (.7 amp) but that is at 42 volts not 120v.
 
Hey alton,
Which driver has a PF of .64? That is not a very good value. I agree with you that there are several other options out there with much better power factors.
Landon
 
Last edited:
alton said:
What LED Driver? I only gave the one I saw posted very early in this post. If you give me the specifications of a particular driver I can give you the results. With most LED systems you are not going to have a driver that has a PF that poor and most of them are dimmed down, example I have a friend who has the aquailluminations running at only 70% so there is more savings. I think everybody is missing the big point if you have an 80 watt LED light that draws 120 watts but you are replacing 250 watt MH that draws 270 watts then you are saving over 50% on your energy and air conditioning bill.
Click to expand...

Here are Kill a watt readings for AI Sol.

http://www.thereeftank.com/forums/f267/aqua-illumination-led-156441-2.html

Apparently, the fans and drivers use 11 watts and the LEDs use 144 watts.
 
You must log in or register to reply here.

Similar threads

sickman
Juwel Lido 200 - really reef tank ready all in one? Really Really?
2
Replies
39
Views
1K
Reefing102
Reefing102
F
New Reef - Need recommendations
Replies
13
Views
2K
Cdentata
C
A
Choosing a Canister Filter for 55-gal Saltwater — OASE Biomaster Thermo 600 vs EHEIM Classic
Replies
2
Views
2K
griss
griss
A
Choosing a Canister Filter for 55-gal Saltwater — OASE Biomaster Thermo 600 vs EHEIM Classic
Replies
4
Views
1K
vlangel
vlangel
LClay
Turning rusty water collector into outdoor pond
Replies
14
Views
2K
SantaMonica
S
Back
Top