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Analyzing electrical usage by system.

sfsuphysics

Supporting Member
For the past couple weeks I've been getting a bit antsy about my tanks electrical usage, I have the two tanks.

One tank uses 17.6 kWh per day, the other tank uses around 10kWh per day. So I figured man I need to switch out to LEDs to bring those down, however a quick analysis of the situation told me I shouldn't even bother with it (although I think I might anyways just for kicks and giggles). I could have figured this out a bit earlier mind you if I simply did the math, but looking at my smaller tank (the anemone one) I was shocked to see it so high since I only have a 175w MH plus a couple 24W T5s over it, and I use a LOT more lighting for the 180g tank.

Lets just analyze the big one, and I'm going out on a limb and estimate with 100% efficiency of the ballasts since they're electronic (I know it's an underestimate but not by that much). halides 500W x 5.5 hours a day = 2.75kWh per day, Blue t5s 220W x 9 hours a day = 1.98kWh per day, actinic t5s 110W x 11 hours a day = 1.21 kWh per day, 1 return pump 50W x 24 hours per day = 1.2kWh per day, 4 vortechs ~ 80W x 24hrs a day = 1.92kWh per day.

Lights
2.75
1.98
1.21

Pumps
1.20
1.92

= 9.02 kWh per day, with only about 6kWh per day of that being light.

So ignoring the power my controller takes, the top off pumps that work for very little time, and the 3w fuge light, about 8.6 of that is electricity used to heat the tank. So my 2-300W heaters on on more than 14 hours per day to keep it at a relatively cool 76°. So I think this is the place that I need to attack as far as keeping electrical usage down.

Some ideas that are running through my head.
--Cover for the sump/fuge areas with acrylic, cut holes for pipes and what not, that should keep the evaporation issues down a bit, there's still the tank itself, and i think I might have an idea there, a switch to LEDs (DIY versions) I could cover the top and poke holes just large enough for the lenses to fit through. Downside to this however would be condensation all over the lenses (might affect light), plus gas exchange might become problematic.
--wrap foam around sump/fuges. This one almost seems like a no brainer, even though I do like looking at my little critters swimming around the macroaalgae it might help a bit to insulate that. For the main tank, this is not an option.
--Move tanks back upstairs, although the house itself isn't kept much warmer than the basement, as the day moves on it definitely gets warmer upstairs.
--Insulate the entire fish room area, this would be an expensive and time consuming task as I'd basically have to remove all the drywall to add the insulation, plus the humidity would become problematic to the point where I might have to put in a fan to pull air out (more electricity being used)
--I could try to build a nifty gas powered heat exchange unit like Chicken did, but that might be a last resort, however a solar powered water heater style one might be nice to at least keep the heat up during the day.

Now why am I getting am I trying to figure things out? In a nut shell, I live in San Francisco, and in the summers PG&E has decided that in this area we should only use 8.3 kWh per day (baseline)... so doing the math 17.6+10=27.6kWh per day which puts me at 333% baseline usage, which might get a bit problematic for my electricity bills, doubly so because that is ONLY the tanks not rest of house usage. Which if they do get too problematic, I'm going to veto the wife on wanting to keep the anemones and leathers that are in one tank, and break that one down completely, which would help a bit, but still put me in a bit of a pickle. Granted it has been unusually cold recently, so that could have a significant affect on how much juice the tank is using now (when I recorded the numbers), but we shall see.!

If anyone else has updates feel free to put them in. I'm going to see what I can do with the steps above and see how that impacts usage, granted all parameters aren't going to be the same, because it is starting to warm up, but we'll see.
 
I'm antsy too a little, partially due to cost, partially due to not wanting my lady to bust my balls. And I'm not even using that much power (yet). Definitely wrap everything you can. I believe I realized a ~15% duty cycle reduction (on ~550 watts) for my SCR-based system once I went with 3/4" foam around all 6 sides of the sump, and wrapping the tank. I'm top down so 5 sides of the tank are a no brainer. Even insulated the plumbing.

I often times put a lid on the tank at night since the temps dip into the low 60's. I've thought about heating the garage, but haven't done the math.

I wasn't recording the duty cycle on the heater controller so not exactly sure, just sort of noted the duty cycle change in the back of my head keeping the ambient environment the same...
 
My heaters almost never come on.
I have had a Killowatt meter on my heaters for over a month and they have used a whopping 1.5 kwh.
Why you ask?
1. I designed it that way. :D
2. My return pumps cool themselves (heat tank) with tank water. (Titanium PS4)
3. In wall design creates a fish tank room that is climate controlled by an exhaust fan with a green house thermostat.
4.The fish tank room walls ceiling and floors are insulated.
5. when I'm in the fish room I radiate body heat also used by the system.

I addition to those energy saving methods I also used a light mover to move 2x 250w metal halides back and fourth across the 6 foot span of the tank.
This device uses 5.5 watts and it eliminates the third 250w MH that most would want.


If I were you Mike, I would encapsulate the entire fish room area and just use an exhaust fan on a thermostat.

My tank thread has most of these details.
 
Smart design!!

Working in ambient approaching 20 degrees less than tank burns your wallet. Got to start by minimize that delta (encapsulation) or reduce radiation losses (insulation).
 
Dave: Yeah I'll wrap everything up to be sure that seems like the cheapest and easiest solution, low 60s? HA! Try low 50s for my fish room! It was about 58 this morning when I checked power usage.

Jon: Yeah, I realize return pumps basically act as heaters, however my return pump is only 50 watts so it's a 50 watt heater which doesn't do much :D Plus having an insulated enclosure (fish room/work area) would definitely go a long way, I thought about building one downstairs, but don't really feel like making it all stick out like a sore thumb. I think working on sealing that room up would probably go a long way to helping with heat, just need to deal with the humidity issues as well.
 
Jon, does a light mover work over a 3' or 4' tank or they are just sold as 6'+?
If one reflector/MH can be used, it would save some $
Our place is pretty much temperature stable either winter or summer time I too use a small heather 100W that does not seem much action, heath is also provided by a Mag return plus the skimmer pump.
I have a frag tank 48" with 324W of T5, a single 175W on a light mover can mean lots of savings over time; tank is shallow ~16" so no need for 250W
 
do you have a canopy over the display or is is open top?

this is my idea for you.

I know for sure if you got a 4 sided canopy and put a 4"12v dc exhaust fan on the sides which were connected to a temp controller with probe in tank so if tank got too hot it would pull some hot air out you could use that heat from the halides to keep temp up, the you wont need to worry about insulating the fuge, also you would still have plenty of oxygenation of the water since no covers are necessary.

again this is just my idea for you, but Im sure it will work with the lighting you have.
 
xcaret said:
Jon, does a light mover work over a 3' or 4' tank or they are just sold as 6'+?
If one reflector/MH can be used, it would save some $
Our place is pretty much temperature stable either winter or summer time I too use a small heather 100W that does not seem much action, heath is also provided by a Mag return plus the skimmer pump.
I have a frag tank 48" with 324W of T5, a single 175W on a light mover can mean lots of savings over time; tank is shallow ~16" so no need for 250W

You can cut the track to any size.
The stops are adjustable.
 
sfsuphysics said:
I think working on sealing that room up would probably go a long way to helping with heat, just need to deal with the humidity issues as well.

The exhaust fan pulls out the humidity. If the room is truly sealed and insulated it will heat up enough for the fan to keep the room at a fixed temperature. I have mine set at 72 degrees for the room temp and my tank stays at 76.5-78.5 degrees with the exhaust fan cycling on several times a day.
 
I as well use an inline fan to exhaust fan but mine simply turns on when the lights do. I love it. Moves way more air then those little biscuit fans and it's much more quiet.
 
fan.jpg


Those are called biscuit fans, amongst other names.
 
go to the hydroponics store and check em out! I am debating getting some sort of dedicated air exchange system for my garage since it's cold and humid I often see light condensation on the windows. My current solution is a small fan pointing toward one of the garage vents near the floor. Works, but could be improved.
 
Well simply closing the doors to the fish room at night (the cats require an entrance through it to go outside :D) the morning ambient temperature of the room was 64° (that's farking warmer than anywhere else in the house!!!) and I notice the heaters used about 9kWh in 2 days, so basically it cut the electrical usage of the heaters in half. However like I mentioned before, different outside temperatures (it wasn't that cold the last couple nights) could easily skew those results.
 
More fun electricity facts!

It takes about 8000 BTUs to evaporate 1 gallon of water, but what the hell is a BTU? Translated 1 BTU = .293 kWh

So that means every 1 gallon of tank water that you evaporate when the tank isn't overly warm, adds about 2.3kWh to your electric bill, think about that!

Also shows why evaporation is such an effective way to cool a tank!
 
I have always just used a fan controlled by my aquacontroller instead of a chiller.
Chillers seem like a waste if you can aim a fan at the tank or the sump.
 
This may not be applicable to your system, but for my inwall tank with the back inside the garage, during the summer, the garage would turn into a baking greenhouse due to the halides. I actually would have to leave the garage door open on hot nights just to keep the heat down.

When I redid my roof recently, I had the roofer install one of these guys:

http://www.ventingdirect.com/broan-350-1050-cfm-roof-mounted-model-350/p968257?source=TREML_OrderConfirmation
350bk-l.jpg


Works fantastically. I don't think I will need a chiller this summer and the best thing is that it's temperature controller is built into the unit. Easy little screw dial lets you set when the fan turns on. I like using this separate controller because then there's less dependency on the aquacontroller. Cheap too!
 
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