LED savings over MH

[NatureNerd]

How many VHOs did you have? What is your electric rate?

I had two 48" bulbs: one actinic, one 50/50. They ran for 6 hrs each day. The MH's ran for 11hrs.

Electric rates are a little hard to determine, as baseline is just 0.12 /kWhr but the rates go up to 0.34 /kWhr at the high end. Baseline usage is just 330 kWhr's. Most families use significantly more than that even without a glass, multi-thousand dollar home for wayward corals. For my household, where we use ~700 kWhr's, the reef tank useage is all at 0.34 as it really is an "extra" non-essential.

 

[kdeyarmin]

The result... .76 a day to run my MH's - which equates, for my electric charges, 22.50/month. The electric rate that I used was .076 /KWH, which I have to say, having read this thread, I am lucky to have it that low. I am going to do my sump/refugium next, but all I have in there is a 1400gph pump, a flourescent light and a protein skimmer. Can't imagine it is even a few dollars a month.
The other unanticipated result of MH's is the residual heat that I get for my room.

 

[dlp211]

The result... .76 a day to run my MH's - which equates, for my electric charges, 22.50/month. The electric rate that I used was .076 /KWH, which I have to say, having read this thread, I am lucky to have it that low. I am going to do my sump/refugium next, but all I have in there is a 1400gph pump, a flourescent light and a protein skimmer. Can't imagine it is even a few dollars a month.
The other unanticipated result of MH's is the residual heat that I get for my room.

7.6 cents. I envy you my friend. I am just shy of 20 cents a kwh. LEDs make more and more sense the more it costs per kwh.

 

[tahiriqbal]

What happens to the electricity used? Either it is converted into light and then converted back into heat when it reaches the tank or it turns into heat in the LED and is dissipated thru the heatsink into the room. Either way, if it uses electricity it makes heat.

Halides are usually passively cooled so the heat that comes off them goes up into the room and down into the tank in the form of light energy just the same as LED. The major difference is watts used, usually LED systems use less electricity so less heat. Saying LED doesn't transfer heat to your tank is false.

Would you like to shed some light as how much a decent LED lighting system with active cooling system may add heat to your fish tank? Majority of LED lighting fixtures are hung up reasonably high when compared with halide and T5 lighting fixtures, which means LED fixtures are in better position to receive ample fresh airflow from ambient room temperature. When you say LED produce heat, yes they do but with active cooling you can keep the heatsink and room temperature in balance hence very little or no chance for heat to transfer.
Tahir

 

[m2434]

It's my understanding that LEDs, PAR for PAR aren't more efficient than halides per say. The difference is that they direct light better. If you consider total light output, halides are still more efficient, but halides don't necessarily get the light were you want it, so, a lot is wasted that way. I should note LEDs are more efficient lumen for lumen, but this is a useless matric, you could have 20 lumens of green light and 1 lumen of blue light and exactly the same PAR. Lumens are weighted to the sensitivity of the human eye, which has nothing to do with photosynthesis.

I always use the rectangle example. If you have a square and put a halide over it, the halide will illuminate it well, as it's designed to light a circular area which is close to a square for most purposes.. If you put that halide over a rectangle, it won't illuminate it well, a lot of light will be wasted over the front or back, or you'll only illuminate a small part of it and then it may be low enough to cause heat issues. If you want to illuminate a tank PAR for PAR, with exactly the same spread as a halide though, on a square tank, you won't really get an improvement. Many people do see an improvement, but that seems to be more because their PAR numbers are lower (on average, not necessarily at the brightest area). If you light a rectangular tank though, you can basically double the efficient, just because your fitting the shape of the tank correctly. Many people do seem to do a bit better than this though. I think this is because, halides are roughly the same price regardless of wattage, so, people are using much more halides than they need, so, there is room to decrease this as well. Or people are using inefficient reflectors with their halides, such as parabolic "spider reflectors" etc...

This article shows the footprint of various lighting for example:
http://www.advancedaquarist.com/2010/2/aafeature2

As for heat, I believe LEDs still waste more energy as heat than halides, but the heat goes to the back of them, and the heatsink, where it rises and dissipates, rather than the front where your tank it.

 

[GSMguy]

Hey guys, what happens when you go out in the sunlight? Is sunlight warm? The light energy converts to heat when it reaches the water.
How many commercial LED units use 400w?
I've used halides and T5s and never had issues with heat but I know some do.

I totally understand the desire to lower electric bills.

 

[Zalman]

LEDs dont use 400w because they are a more efficient light source. Other bulbs produce heat in addition to light.

 

[GSMguy]

Oh I forgot, LEDs are magical.

Have yet to see an LED fixture that has the PAR and spread of a 400 w halide in a good reflector.

 

[chadfarmer]

Oh I forgot, LEDs are magical.

Have yet to see an LED fixture that has the PAR and spread of a 400 w halide in a good reflector.

i had 250w and 400w and ran a chiller than switched to t5s and the chiller was no longer needed

the thing about leds it that you can dim them down or dim them in to the desired level you want

i do now run leds and i like them i even kept my halides as back ups if i didn't like them

i was do to replace my bulbs on my halides and decided to take the plunge on the leds after having them on my frag tank that grew corals under them.

i went from 700- watts down to Watts and i dim the LEDs for 2 hours up to there peak than do the same later in the night

lots of led bashing just like when i go my t5 light and there was about 8 different bulbs to buy

in the united states we are behind in leds more than other country's that didn't have the patents to deal with

a watt is a watt no matter what you do

 

[GSMguy]

a watt is a watt no matter what you do

that's all im saying. I have no problem with LEDs

I used to run 580w of halide ( the m-80 ballast ran at 290w) now I have 6x39w t5 and only run all 6 bulbs 4 hours a day and 4 bulbs for 12 hours. I did not do it to save money, just to get better PAR, spread and color. If I save a few dollars great. I plan on ordering a small LED for my maroon clown tank for the moonlight similation.

 

[James77]

LEDs dont use 400w because they are a more efficient light source. Other bulbs produce heat in addition to light.

LEDs produce heat as well. You can feel it on your hand underneath the light and you need to use heatsinks and sometimes fans to dissipate the heat so it does not damage the LED. All the energy converted to light will go back to heat as it strikes surfaces in the aquarium.

 

[njreefermadness]

My personal experience is w/ running 3 x 250 watt SE radiums w/ 2 160 watt 6 ft actinic vhos versus 6 AI sol blue modules.

My chiller still runs, but not as much as it did. When I stick my and under my hood, there is a big difference between the MH and the LEDs.

My wattage went from over 1000 Watts, to somewhere around 300 or so.

One thing I did lose was my 750 Watt MH "heater". My heaters need to run a bit more now to make up for this loss of heat input into the tank during the cooler months.

What I did gain was tremendous control over my illumination schedule w/ highly sophisticated dimming and color temperature control that you could never get w/ MH lighting. Not sending numerous bulbs w/ hazzardous/toxic materials to the landfill every year is also an eco benefit as well.

Just my 2 cents.

Herb

 

[NatureNerd]

Just assume that the amount of power consumed, is all going to eventually be heat. Then, the big difference is the LED efficiencies. At the same level of light output, power consumption is way down. In my case, 500W of MH and flour. vs 200W of LED.

Also, look at what spectral bins that light is in. Light not in a bin used for the creation of "food" by the symbiotic algae in our corals is wasted. My old MH's were pretty broad in terms of output. Much of that was wasted. Note that I used 10k bulbs. I have not looked at the spectral output of others.

Next, look at how localized is the heat and how easy is it to remove from your system? LED's have a slight advantage here.

One final aspect in my decision of LED vs MH (after a decade of MH use) was safety. Almost no one mentions this. Because of the awkward nature of my light hood, and maybe my coordination levels, I used to burn myself on my MH's quite often. I also worried about my kids who hand-feed some fish and cleaner shrimps. Not having super-hot bulbs over the tank is a good idea. Not having high voltage above water, another good idea. Not having bulbs that could burst if splashed, yet another good thing. What cost, safety?