Backyard Aquaponics
A place to discuss aquaponics

Hiya folks I was just toying with an idea to heat my systems during the cooler months.

This what I came up with so far.



Feedback or suggestions most definitely welcome

Cheers
VM

I ran 300mtrs of 13mm black pipe on the shed roof and had a pressure pump feeding it from the pool. I could adjust the temp by 10degrees in winter on a 55000ltr pool. Left the pipe up there and may use it for a hot tub later as a pre heater.
It would save a lot of space and joiners etc by having it on the roof. But you need a pump that will handle the head.

be aware of storm water pipe. It can be made of evil stuff. The evil is a 'sandwiched' layer in the wall. This should be sealed. It is easily identified by looking at the cross section, there will be three rings that make up the pipe.

100mm pipe has a cross section of 0.008m²
so for every 2m length you have 0.016m³ or 16 litres
as you have 5 pipes, volume will be about 80 litres

sunload is about 1kW/m² and your pipes will be exposed to approx 1m²

What the heat takeup of this kW though Stormwater pipes will be, or you flowrate, I'm not certain, without trying to figure how much energy you need to raise water temps, which is a bit hard for me without a text book.
If some1 would like to continue this investigation, I may learn some new formulas off the top of me head After all, I'm just a lowly programmer, albeit trained as an engineer.

Taks for that, the PVC I am using is reclaimed from a very old building site, I have used it previously for fish related projects and neither I or the fish have suffered any obvious effects from it.

p.s I have a submersible here that can lift a solid stream of water approx 15' into the air straight from the pump [no reduction in flow] it use to be used to pump out flooded basements etc in shopping centres. Only thing is that it weight a tonne and vibrates quite badly. This led to my liner being damaged the last time I tried it on another growout pond I was running for Cichlids & Catfish



I dont know the actual specs though as the unit is old and a tad on the rusty side! I am thinking that it could be run via a sump tank to avoid age to the FT etc.

Just found some details about the pump:
Brand: Rossiner
Max Head Lift: 11m
Flow Rate: 4 l/s
Voltage: 240v Single phase

Like I said, one powerful pump!

In the midwinter over here what bit of sun we do get may provide 10,700btu/m2 or 3.135kw per day. 80L is 176lbs, so the water in a vertically orientated panel (to catch low angle winter sun) may gain an extra 61F over the full day excluding losses.

thanks Hex is that all empirical data? or is there a way to calculate the 61F?

All you need for the basic calculation is the water weight in pounds and btu input, 1 btu will heat 1 pound of water by 1F, (10,700btu / 176lb is 61F)
Athough technically correct math wise, its a best case scenario. A real system has a multitude of losses reducing the temps considerably.

Ahh yes, I remember now. water is 1.0 calories / gram * degrees Celcius
caloris to watt hours is annoying though... think it's 800 odd.

That's joules KP, and the converstion is 3600 (minutes x seconds)

nope, i'm wrong lol
joules is lifting mass, not heating water

ignore me

hehehhehe Sure Steem
tell me, WTF is a calorie? does it work out to ANY nice metric units? I'm guessing not, as it's = to 4.184 joules.
is a calorie a unit created so that it can equal 1.0 gram degrees of water temp change?

Yep, I think so. can't have it all I guess, 1kg/litre, 1 joule/gram/m lifted, water doesn't have a neat specific heat...4.184
remember also that a Calorie is 1000 calories or something silly like that.

yes, very correct... I want to put out an add for toffee stating less than one Calorie (4kJ)

OK so we worked out how much water could heat if the btu's got into the water. How well will they penetrate Storm water pipe?
What are you losses going to be?

For both these questions we need the thermal conductivity of PVC which is 0.19 W/°C
whereas water is 0.58W/°C
so it is definitely insulative, which means transfer will be slower about 1/3 the speed of water exposed nakedly, or within glass or any other substance with a conductivity above 0.19.

so you could (I think) expect only 1/3 of the 61°F quoted above, although I'd like somebody to confirm this.