Looking for ways to cut operating costs???
- Thread starter smstrick20
- Start date
wld1783
Premium Member
Eductors
I have a 3/4 inch eductor on a closed loop. The pump is an iwaki non pressure 1200 GPH pump rated at 1.2 amps. The eductor lowers the amp draw to .72 amps.
Still more draw than a tunze stream but at less cost.
Flow is similar maybe more than a 3000gph tunze stream.
If you have a seperate sump room...Huge water containers. I dont heat or cool my tanks I let the room do it. My 500 gal mixed reef has 900 gallons of sump. Temp is between 78-80.
Bill
I have a 3/4 inch eductor on a closed loop. The pump is an iwaki non pressure 1200 GPH pump rated at 1.2 amps. The eductor lowers the amp draw to .72 amps.
Still more draw than a tunze stream but at less cost.
Flow is similar maybe more than a 3000gph tunze stream.
If you have a seperate sump room...Huge water containers. I dont heat or cool my tanks I let the room do it. My 500 gal mixed reef has 900 gallons of sump. Temp is between 78-80.
Bill
nycustomsumps
In Memoriam
i recently had 2 -300watt visi-therm heaters on my 180g , i tried a single 250watt jager and it does the job. so i cut some electric use there.
salty joe
Active member
<a href=showthread.php?s=&postid=13961111#post13961111 target=_blank>Originally posted</a> by Randy Holmes-Farley
I recently decided to stop using my Iwaki pumps in winter, and go with submerged pumps. All that supposed benefit of heat not being added to the water is just money out the window when heaters are running close to 24/7 in my tank in winter.
But the heat is coming from electricity either way. So, from an electrical consumtion viewpoint, I don't see how using pumps to heat your water is cheaper than using heaters. But maybe I'm wrong.
BeanAnimal
Premium Member
Sorry, but you did not cut any electical use
1 Watt = 3.412 BTU/hour
You could have had (2) 1,000 Watt heaters and they would use no more energy to heat your tank than (1) 250W heater.
In any case, lets use your example of 600W worth of heat vs 250W worth of heat.
Your tank is 180 gallons, so that is 1530 pounds of water. It takes 1 BTU to raise 1 pound of water 1 degree F or 1530 BTUs to raise your tank 1 degree.
So lets say you need to raise your tank tank temperature 5 degrees daily on a winter day.
It takes 1530 * 5 = 7650 BTUs.
(2) 300W heaters are capable of 2047.2 BTUs of heat per hour. So it would take them 3.73 hours of running per day to keep your tank from losing that needed 5 degrees.
(1) 250W heater is capable of 853 BTUs of heat per hour. So it would take it 8.9 hours of running per day to keep your tank from losing that needed 5 degrees.
Now lets say your electricity costs $0.15 per kWh.
the (2) 300W heaters run for 3.73 hours. They consume 2.23 kWh of electicity per day. That is $.34 cents
the (1) 250W heater runs for 8.9 hours. It consumes 2.23 kWh or electricity per day. That si ALSO $.34 cents
BeanAnimal
Premium Member
The Iwaki is an external pump and therefore does not impart all of its energy into the water. On the other hand, the submersible pump does.
In other words a 100W external pump may put a few watts worth of heat into the water and the rest would have to be added by a heater. So to get 100W worth of heat Randy may be using nearly 200W worth of electricity. That is, not all of the water pumping energy is being used to heat the water. A 100W submersible pump WILL put 100W worth of heat into the water, eliminating 100W worth of heat that a HEATER needs to add. So Randy is using the same energy to heat the water that he is using to pump the water.
Freed
It's what it's
Check into "Time of Use" metering with your electric company. I have a couple thousand watts of electric use per night and only pay $0.02 per kwh. Will save you massive amounts of money if your electric company offers it. Some do and some don't. Some look into, some don't. Those that do save hundreds of $$ per year. Those that don't, well, they keep moaning and groaning about how much $$ they spend on their tanks a year 
BeanAnimal
Premium Member
The 100W submersible pump puts 100W worth of energy into the water. MOST of it IS heat transfered by condution. The rest is sound (vibration) and energy used to move the water, most of which turns to heat due to friction
So in reality, a 100W submerged pump and a 100W heater both put about the same amount of real world heat into the water.
liveforphysics
New member
That's very correct Bean.
I'm thinking of trying something related to this to lower the energy usage of my reef. I'm considering altering my plumbing to enable using a Laguna 2400 as my return pump in winter, and then flip a couple valves and go back to my Dart Gold pump during summer.
Submersible helps keep tank warm in winter, external helps keep it cool in summer
I'm thinking of trying something related to this to lower the energy usage of my reef. I'm considering altering my plumbing to enable using a Laguna 2400 as my return pump in winter, and then flip a couple valves and go back to my Dart Gold pump during summer.
Submersible helps keep tank warm in winter, external helps keep it cool in summer
BeanAnimal
Premium Member
That is pretty much what Randy is up to. He did not have good luck with the (2) lagunas he replaced the Iwakis with. But I think he is getting an RD in the mail to play with instead.
BeanAnimal
Premium Member
Don't be embarrassed... I would guess that 95% of the college graduates here don't grasp that basic tidbit of physics and there is nothing you could do to prove it to 70% of that 95%
liveforphysics
New member
Shaft failure perhaps? I might just either buy Red Dragons from the start then, or replace the shafts with tungsten rods myself. I really don't like submersable pump design, but it seems like a waste not to capture that heat energy during the seasons that you can take advantage of it.
BeanAnimal
Premium Member
I think Randy shipped the pumps back, but may be able to offer more insight into the problem. My guess was simply poor QC.
The Velocity T4 pumps are water cooled external pumps. The "wet end" is a titanium cup coupled to the motor windings. They transfer most of their heat to the water. They are dead silent.
The Velocity T4 pumps are water cooled external pumps. The "wet end" is a titanium cup coupled to the motor windings. They transfer most of their heat to the water. They are dead silent.
therealfatman
In Memoriam
There are head loss calculator programs that actually show how much of the electrical energy is actually transferred to pumping water and how much is lost as heat. That loss energy by the external pump is in large part will be gained as heat energy with a submerged pump. However not all the heat energy. There is no such thing as a free lunch. Heat loss due to friction in piping is lost to the air as thermal energy (heat) with an external pumps plumbing lines as well as a submersible pumps plumbing lines.
The outside of the water piping system is not surrounded by the water system so all energy is not reabsorbed by water and is therefore lost. You will not get a net heat gain equivalent to 100 watts thermal energy using a submersible pump as a return pump. For all energy to be conserved the entirety of the system would have to be inside the water body. Therefore the external plumbing negates the concept of the submersible pump transferring all energy to the water. If you merely put a running pump in a perfectly insulated tank and did not circulate water in or out of the tank with the submersible pump then all thermal energy would be conserved. Once that sytem has an exit for thermal energy outside its self the conservation of energy is no longer conserved as there are losses to the surroundings.
Stating that all energy that a submersible pump puts is transferred to the water is misleading as it is system energy that is important and losses are experienced by both pump energy systems. A submersible pump only transfers all that energy to the system initially but it is not equal to the same wattage supplied by a heater as the heat losses are different. The heater is suppllying all its thermal energy to the sump water. The submersible is giving up part of its thermal energy to the surrounding air through plumbing friction heat losses in the piping and that can not just be ignored as the heater does not have those additional losses. The heat from the submersible is only equivalent to the heater in its efficiency in the sytem if the water going in and out of the submersible never leaves the sump. Yes it is more efficient than the air cooled external pump as it supplies some of its wasted heat back to the system but no it is not 100% efficient in supplying all wasted heat back to the system as it still gives up energy to the systems piping.
It is possible with the other head loss calculator to calculate the payback period of buying submersible pumps in order to use them just during the winter rather than the external pump(s) used during the summer. Personally I have found with out fans on at night over the tank and sump I do not need additional heat at night, but I also maintain the same room temperatures day and night.
It would take a good deal more than a few calculations to come up with that accurate answer though. If your night time room temperature is not maintained at 70 or 72 degrees though, and your electrical rates are high and your system is fairly large (150 gallons with sump etc.) a repay might happen in a few years. Water stores a lot of thermal energy while the lights are burning so a lot also depends on what size tempearture swings you find exceptable after the lights go off. Plus a reverse cycle light over a refugium also aids in temperature balance lessening the needs for night heat and lessening night time circulation needs.
However, when it comes to pumping water the easiest thing to remember is the most expensive water to pump is any water that has to be pumped up to the tank that is not part of a closed loop system. Draining more water to your sump than the skimmer and a refugium might need in order to pump it back up to increase tank circulation is the least efficient form of circulation.
The outside of the water piping system is not surrounded by the water system so all energy is not reabsorbed by water and is therefore lost. You will not get a net heat gain equivalent to 100 watts thermal energy using a submersible pump as a return pump. For all energy to be conserved the entirety of the system would have to be inside the water body. Therefore the external plumbing negates the concept of the submersible pump transferring all energy to the water. If you merely put a running pump in a perfectly insulated tank and did not circulate water in or out of the tank with the submersible pump then all thermal energy would be conserved. Once that sytem has an exit for thermal energy outside its self the conservation of energy is no longer conserved as there are losses to the surroundings.
Stating that all energy that a submersible pump puts is transferred to the water is misleading as it is system energy that is important and losses are experienced by both pump energy systems. A submersible pump only transfers all that energy to the system initially but it is not equal to the same wattage supplied by a heater as the heat losses are different. The heater is suppllying all its thermal energy to the sump water. The submersible is giving up part of its thermal energy to the surrounding air through plumbing friction heat losses in the piping and that can not just be ignored as the heater does not have those additional losses. The heat from the submersible is only equivalent to the heater in its efficiency in the sytem if the water going in and out of the submersible never leaves the sump. Yes it is more efficient than the air cooled external pump as it supplies some of its wasted heat back to the system but no it is not 100% efficient in supplying all wasted heat back to the system as it still gives up energy to the systems piping.
It is possible with the other head loss calculator to calculate the payback period of buying submersible pumps in order to use them just during the winter rather than the external pump(s) used during the summer. Personally I have found with out fans on at night over the tank and sump I do not need additional heat at night, but I also maintain the same room temperatures day and night.
It would take a good deal more than a few calculations to come up with that accurate answer though. If your night time room temperature is not maintained at 70 or 72 degrees though, and your electrical rates are high and your system is fairly large (150 gallons with sump etc.) a repay might happen in a few years. Water stores a lot of thermal energy while the lights are burning so a lot also depends on what size tempearture swings you find exceptable after the lights go off. Plus a reverse cycle light over a refugium also aids in temperature balance lessening the needs for night heat and lessening night time circulation needs.
However, when it comes to pumping water the easiest thing to remember is the most expensive water to pump is any water that has to be pumped up to the tank that is not part of a closed loop system. Draining more water to your sump than the skimmer and a refugium might need in order to pump it back up to increase tank circulation is the least efficient form of circulation.
Last edited:
BeanAnimal
Premium Member
fatman, please read what I said again:
You state that my remarks are misleading. They are not not misleading at all. We do not need quantify every last electron and where its energy is transferred. In other words, you are taking a very simple concept and making it unendingly complex for our purposes. "Most" will do for our purposes. I.E. "ALL" simply makes no difference in our frame of reference. In the real world, most of the energy consumed by a submersible aquarium pump ends up as HEAT in the aquarium. No need for complex equations or calculations.
This same discussion has played out 20 times here and each time, somebody wants to count the particles to prove that not 100% of the energy is retained as heat. Shall we talk about entropy while we are at it?
You state that my remarks are misleading. They are not not misleading at all. We do not need quantify every last electron and where its energy is transferred. In other words, you are taking a very simple concept and making it unendingly complex for our purposes. "Most" will do for our purposes. I.E. "ALL" simply makes no difference in our frame of reference. In the real world, most of the energy consumed by a submersible aquarium pump ends up as HEAT in the aquarium. No need for complex equations or calculations.
This same discussion has played out 20 times here and each time, somebody wants to count the particles to prove that not 100% of the energy is retained as heat. Shall we talk about entropy while we are at it?
Last edited:
in my efforts to economize, I use a dart as my main return pump..using a manifold it feeds my tank and UV sterilizer, phos reactor,calcium reactor,and skimmer not too bad for 180 watts..
250watt mh with good reflectors instead of 400 watters...(cuts heat and energy)
evaporative cooling with a kalk drip...
but my best idea was to move my chiller to the crawlspace under the house, directly venting the heat out a foundation vent..this increases its efficiency immensely. (compared to it heating the fishroom)
250watt mh with good reflectors instead of 400 watters...(cuts heat and energy)
evaporative cooling with a kalk drip...
but my best idea was to move my chiller to the crawlspace under the house, directly venting the heat out a foundation vent..this increases its efficiency immensely. (compared to it heating the fishroom)
Similar threads
