• Lighting choices that save energy

    Hi Melev,

    I've seen your posts and tanks and was wanting your opinion regarding my lighting options. I currently have a 180-gallon 72" x 24" x 24" tank.

    The two options i am looking at are:
    1) 3 X 250w MH Lumenbright Mini Wide with 12,000K Reeflux bulbs.
    2) 3 X 175w MH (same as above)

    These thoughts are what i am taking into consideration.

    1) Electricity is about $0.23 kWh + fuel adjustment = approximately $0.24 kWh - $0.30 kWh.
    This is what i care about the most.

    2) Heat - I'm trying to run my tank with as little equipment as possible, ie. if I can stay away from a chiller or fans, I will be over the moon.

    I don't have a hood on the tank. I want to hang the lights above the tank in pendants.

    Does a 250w produce way more heat then the 175w bulb?

    What you think?
    Help please.
    Dru
    Hi Dru,

    Yes, they will add more heat since they uses more wattage, but the pendants do a great job of keeping the heat above the tank and off the water's surface. They hang up higher so you don't have to worry about direct heat transfer, owing to the glass shield and vent slits in the painted housing.



    One or two IceCap 120mm fans blowing across the surface will easily keep the aquarium chiller-free, with very low wattage use. You'll want to put those fans on a timer to turn them on for the exact amount of hours needed, and no longer. Otherwise the tank may run too cool during the night or early in the morning, which would turn on the heaters - using more power again and again. Try to find that sweet spot and power the fans only when they are needed, reducing the frequency that the heaters have to kick on and you'll be saving power every day. Your monthly electric bill will reflect that greener-thinking too.

    Mathematically, let's look at the difference with your electric bill, based on the numbers you provided. If you ran each bulb for 7 hours a day:

    3 x 250w: 750w per hour, or 5.25 kWh daily. At $0.26, it would cost $1.37 daily or $40.95 per month.
    3 x 175w: 525w per hour, or 3.68 kWh daily. At $0.26, it would cost $0.96 daily or $28.71 per month.
    2 IceCap fans use 12w of power, or about $0.94 per month at 10 hours a day.

    Thus, you can expect your lighting and fans to cost less than $45 a month even where your electricity rates are quite high. You won't need a chiller, which saves around 600-800w per hour on average. I live in Texas where we have very hot summers and we have to factor in humidity. In all the time I've been in the hobby, I've never needed a chiller on my tanks. (Admittedly, my 280-gallon reef is in a fish room which has its own air conditioner unit to keep the room at 74° to 76° F, which costs $34 monthly each summer. You can read more about that power usage here.)

    For your tank, you could use 175w bulbs if you like. You will have more choices with 250w bulbs, but it will cost you $147 more per year. If you can afford it, that is.

    Happy reefing,
    Marc
    Comments 7 Comments
    1. drakedeming's Avatar
      drakedeming -
      Any idea how much your whole tank costs per month melev? Never mind I found it.
    1. melev's Avatar
      melev -
      I snuck it in there, Drake. It's just easier to cross-link some of the stuff I've posted in the past on my other site.
    1. Trido's Avatar
      Trido -
      Melev, did you happen to log all of that data into an excel program that you might be willing to share? I like the way its laid out and dont really want to create one.
    1. melev's Avatar
      melev -
      Yes, I usually use Excel when tracking various information. That being said, it wasn't like the cells were actively doing math, if I recall correctly. I'm happy to share it with you if you like.
    1. cornhusker85's Avatar
      cornhusker85 -
      Have you considered T-5's at all?
    1. Murfman's Avatar
      Murfman -
      Mark, I am waiting on the Photon Canon, by Ecoxotic to be released. I saw them at Reefstock in March and they really look promising. Info is scarce on them, out here on the web. Here is what the company owner told me at Reefstock. They are a 50W led array that puts out more than a 290W MH.They will come with either a round circular reflector or oblong, for skinny tanks.They are pendants.July/Aug specs should be released on the lights with numbers and then be up for sale.I am seriously considering replacing my 400W MH with these. Any opinions? I have a 30" deep, 300 gallon tank with 3 400W MH. I was figuring that since I only have SPS on one side of the tank that they will be high enough on the rocks that they will be fine and my lower light corals will be happier.
    1. melev's Avatar
      melev -
      I got to see something new in the Ecoxotic booth at MAX last month. It looked like a camera's lens, hanging over a shallow 16-gallon system. It's too new for me to give you any kind of opinion for or against, so get one and give us your review.