LED Question

[Foody]

I am looking at a 72x3 watt, 48 inch LED fixture to put over my 55gal. Can anyone tell me how the energy consumption of this fixture would compare to my current 36", 4 bulb, 156 watt T-5 fixture? My current fixture costs me about $1.50 per day or $45-$50 monthly. Thanks!

 

[SkiFletch]

Well, if the LED setup you're looking at contains quality LED's, first off you're talking a bigtime increase in light over the tank. Like double or triple the amount of PAR, perhaps more depending on how they're arranged over the 55. 72 lamps over a 48x12" footprint is a significant amount. If you want an energy efficiency comparison, you'd need to compare to at least 6x54watt T5 or at least dual 175watt metal halides (more like dual 250s IMO). Furthermore your T5 fixture is not 100% efficient. Four 39watt lamps make you think 156 watts, but you loose efficiency in creating the proper voltages to drive the lamps within the ballast. If it's electronic, somewhere around the 15% loss, if it's magnetic, more like 30%. So your fixture is techincally drawing somewhere in the neighborhood of 180-200 watts from the wall. Not sure where/how you're getting the $1.50 per day, that seems high even estimating 156watts for 8 hours per day.

Ultimately to answer your question, your current fixture is drawing 180-200watts from the wall. The LED's would draw ~260watts from the wall while a dual 175 halide setup would draw ~420 watts, and a dual 250 halide would draw at least 600 watts. I used to have a dual 175watt halide setup over my 65g (36x18" footprint). I upgraded to 72 LEDs. My PAR values with the halides were ~300 at the surface and ~80 at the sand. With the LED's, I've got ~500 at the surface (highly variable though being so close to the lamps) and ~150 at the sand. That's why I suggest that 72 3-watt lamps is more like a dual 250 setup when comparing LIGHT.

The discussion is never simple

 

[Foody]

More simply asked, would the switch save money, be equal or cost more money?

 

[SkiFletch]

Slightly more money, more than double the light for your corals. If you wanted the same amount of light, you could go with a fixture with fewer LED's

 

[E_rock]

You can contact your power company to find out what they are charging you per kilowatthour, if you want more accurate estimates. It's pretty simple math from there. Should be somewhere around $.15 per kwhr

 

[E Rosewater]

The money savings really comes in the way of bulb changing. I built my 6' LED fixture for under 1000. Which is cheaper than any non-LED facotry light alone. But had I gone with a standard 8 x 39w and 3 x 250w. That would be 350 in light bulbs every 10 months.