MH vs LED current draw?

poksal

Well? .. I AM trying
OK.. I am running four 100 watt MH lamps and actually put an amp clamp on the power leg of the incoming supply line and got a reading between 7.5 and 8 amps. (between is because my clamp was only that consistant between several readings)

Does someone running LED's with similar light output,( my tank tank 95 gal 22-1/2" of water depth) have access to equipment to actually take a current reading on their supply line?

Let's get readings here and not what the box and manufacture claims.. my lamps claim .8 amps but actually draw almost 1.8 & 1.9 (it does vary some per bulb).
Let's be careful to only read the LED current draw and a draw of the total group. For example I have additional 36" bulbs but did not include those in my readings.

Please don't use this thread to state a bunch of manufacture claims. What the engineers designed and what the manufacutres produced now days often has little to do with what marketing states on the boxes and on commercials.

Clearly, IF, the advertised differences in current draw are as stated it is easy to figure out that we will be able "pay for" our LED lamps. BUT let's prove it.



Perhaps someone has made the change and has REAL data, (meaning facts).

Please let's don't derail this thread to talk about the heat differences, the heat loss differences are clearly also in favor of the LED's.

I realize that this will not be a perfect model as we will be getting data from different soucecs but it is a reaslistic enough model... I will next take the data and attempt to get a realistic $$ saved per year at a given cost per KWH.
We can chase the heat in another thread, next if desired.

Thank you for your efforts in this matter, ... OR... has someone already done this???


.....This will help me justify buying LED's.... to my wife... ;)
 
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I = P/V

Amp = Watt/Volt

On a 3 watt LED using 110V,

3W/110V = ~0.027mA

Math is not a claim, it is fact. Obviously there are many factors when dealing with this kind of measurement; as you said, heat transfer, bumps in current etc, but if you want to know how much energy you are using, just do the math. If you have any sort of Calculus background you can account for other factors as well. I agree that the stated, "light output" on a box may vary a bit, but if you know the wattage of the LED's, and you know the current in your home, you can do simple algebra to figure out most of this stuff.
 
all true.. and that is no problem.. (I've done energy studies, you don't even need calc), but I'm looking for actual readings from member's amp gages... the stated watts and current draws on packages, paper work, and advertisements are not reliable. ...smile...

For example my whole aquarium package is drawing about 1.315KWH or around $35 per month average standard american rate.

Thank you
 
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I know several months ago someone posted actual differences in their monthly electric bill when they switched from MH to LED. Can't for the life of me remember who or the thread, but I do remember the savings was significant - like a couple hundred a month difference
 
I know several months ago someone posted actual differences in their monthly electric bill when they switched from MH to LED. Can't for the life of me remember who or the thread, but I do remember the savings was significant - like a couple hundred a month difference

This, I'm not buying. No matter how big your MH lights are, they are not going to eat up a couple hundred a month. I did the math when I had a 240 gallon, with 1,200 watts of lighting. Ruining it for 12 hours a day, with what a kilowatt hour costs, it wasn't hundreds. When I did the math for my 90 gallon, it was next to nothing, and since I got rid of that tank, there hasn't been a noticeable difference in my electric bill.
 
+1 bif

It would take several tanks with MH as in a professional business or public aquarium, I'd think. $200 per year.. could be.



...3 watt LED.... times how many 3 watt LED's does the bank have in it..?? for example.. but that is still calling it by the advertised current draw... and is not real data... I suspect it is higher than expected... or claimed.. but...I have no clue at this time...
 
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(I know this is the manufacturer's claim of wattage used, BUT it can give you a very solid estimate)...

Based on the lights I had over my 90 gallon (6 x 54 watt T5 = 324 watts).
324 watts x 12 hours a day = 3,888 watt hours = 3.888 kw hour
3.888 kwhours x 30 days in a month = 116.64 kw hours per month
My electric company's residential rate is 9 cents per kilowatt hour, or 0.09 dollars.
0.09 x 116.64 = $10.48 a month to run the lights.

Now for my metal halide over my 240 gallon, which were 4 x 250 watt MH plus 4 x 39 watt T5 (1,156 watts):
1,156 watts x 12 hours a day = 13,872 watts per day = 13.872 kwatts per day
13.872 kwatts per day x 30 days in a month = 416.16 kwatts per month
416.16 kwatts x $0.09 per kwatt hour = $37.45 a month to run those lights.

It is simply NOT POSSIBLE for the electric bill for lighting to be in the hundreds per month. I highly doubt anyone here had lights that pulled more juice than the lights I had over my 240, and with those, the bill was less than $40 a month, and that's running them 12 hours a day, which is longer than most people run their lights.

Of course, when you have a tank, you have to take into consideration all the other equipment you are using, usually 24/7 -- like powerheads, heaters, return pumps, etc. But those are going to make a dent in your electric bill in the single dollars. It costs nothing near several hundreds of dollars a month in electricity to run your home aquarium.
 
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I find saving hundreds a month by switching to LED very unlikely too.

Let us say that they were running a 1000 watt MH light. Which happens to be 1kW. Picked for easy math of course. And they run it 12 hours a day. AND they happen to live in a place with very high electric rates. like Hawaii at 44.05 cents per kWhr

HECO > Average Electric Rates for Hawaiian Electric Co., Maui Electric Co. and Hawaii Electric Light Co.


So here comes the math
1kW x 12 hr = 12 kWhr
12kWhr x 44.05Cents/kWhr = 528.6 cents = $5.29 per day
$5.29 per day x 30 days per month = $158.70 per month

However, chances are they don't live in Hawaii and have a cheaper rate. The US average was about 11 cents in 2010. (most up to date I could find) And Hawaii was only 27 cents back then.
Electricity Prices by State | Compare Electric Rates by state in Your Area Nation wide
 
Again 1+ bif

though.......My MH lamps (four claimed to be 100 watts each) are drawing 2.25 times the current they are claimed to draw. This means they consume 2.25 times the watts claimed.
My 4 100watts... actually end up being 225 watts each and burn 1.115 KWH. Times 12 hours times 30 days... at (bif's) .09 = $36.13

..but that is enough to make my wife... give me a talking to.... LOL...
 
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This...
I'm trying to justify or NOT justify buying LED's... with data that satisfies my engineering mind set... watts/cost per.... heat losses.... actual light frequencies... light rays actually reaching the bottom of the tank..

you get the drift...

But to keep it straight and simple this thread is power or watts.. and current (AMPS) is the REAL readings to reach pure data.
..... in other words with amps I can calculate actual consumed power, which is watts... which is used to calculate $$ spent.
 
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It doesnt really matter what they are actually using versus what they are rated at.

I replaced 1000 watts of Metal halide over my 180 gallon tank with 225 watts of LED's - and I cant even run the LED's at full power

Even if both were using twice what they were rated for, I still replaced a 1000 watt fixture with one that uses 1/4th of the power. I bought my 6 foot metal halide fixture new, and it wasn't all that much cheaper than a LED fixture. If I were electrically inclined I could have done a DIY setup for much less than either fixture.

I switched to LED's after pricing out a full set of replacement bulbs for my fixture at the 1 year mark. I decided I might as well spend a little more and be done with bulb replacements - which is another cost to figure into the equation. T5's should be changed every 6 months, and halide bulbs once a year
 
Thank you North
This is true..but it does matter what they actually consume because the data on the box is just propaganda by marketers...
Agreed on the bulb replacement... a HUGE factor ..for the full picture.. actual power usage calculates in for the whole picture when figuring savings to justify LED's.. as I started .. this is only the power portion...

to add to your post..if I may... we also have to consider that the technology of LED is a very fast moving industry.. prices will be falling like lead in a pond at some point.. once all the research and production costs have been regained competition will ramp.
Today's best LED's will be old versions soon, and they will become more affordable.
Currently there are LED's for high end projectors so powerful they must be liquid cooled.
 
to add to your post..if I may... we also have to consider that the technology of LED is a very fast moving industry.. prices will be falling like lead in a pond at some point.. once all the research and production costs have been regained competition will ramp.
Today's best LED's will be old versions soon, and they will become more affordable.
Currently there are LED's for high end projectors so powerful they must be liquid cooled.

IMO, the price of LEDs has fallen dramatically! Just a few years ago, you were looking at two grand just to really get into LEDs. Now, though still high, are more reasonable. Still trying to convince my wife to let me drop 3-400 on a nice setup for over my 29 gallon tank :mrgreen:
 
T5's should be changed every 6 months, and halide bulbs once a year

I think you have this backwards. MH bulbs are every 6 months, and T5's are 9-12 months.

I switched over from Dual 250 watt MH, and 4 T5 bulbs to a pair of Radions. No significant difference in energy draw that I could see. My bill is pretty much exactly the same as it was before.
 
There was a study posted on RC that tracked the output of various brands of T5 bulbs and found that they only needed to be changed every 12 to 18 months. I've never heard of them having to be changed every 6 months.
 
Boys & Girls.. FYI

I have ordered the 90 gal tank dimmable LED set from RapidLED. Had a good conversation with mike. I will post the current draw compared to my MH as soon as they are wired and running.

The deciding factor was the replacement costs of MH & T-5 bulbs over the life expectancy of the LED units. .... at 12 hours a day X 365 that comes to 4380 hours per year / into the expected 50,000 hour est life of the LED's = 11.xxx years. figuring the cheapest MH bulbs at (in my case) a minimum of $200 per year that alone comes to over $2K... then there is the heat in the heat in the summer, and the T-5's to replace for 11 years... a total no brainer... I do intend to maintain one pair of T-5's in a more of a full spect. grow light temp and selected a higher % of blue LEDS with that in mind to get the most punch for the buck.

With 4 dimmer pots & 10 volt power supply to provide the 0-10 VDC to the dimmer inputs with shipping it came to an even $500. With that package I will also receive one non-dimmer driver I can use to power the few purple and green LED's. This allows me total control of the white and blues with them wired to 4 dimmable driver units.

I'll update as data is available.....

Until then, thanx for all your informative and/or interesting inputs...:)

-randy-
 
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