Heat extraction, pond dimension, Lima-1

[thermopat]

Hello

Does someone knows how to determine the seize & volume of water required in a pond to ensure regeneration of extracted heat in winter conditions?

If a pond is too small and we use a compact heat exchanger like Lima-1, does global pond temperature could cool until 32*F and then freeze completely?


Patrick
Thermopompes Saguenay
Chicoutimi (QC) Canada

[Palace GeoThermal]

Yes, you could freeze the pond.

[waterpirate]

Useing an exchanger that is compact in a pond that is potentially to small would not be adviseable.. I thought I read somewhere, prolly here that 1 acre in size is the bare minimum for pond size, and even then more engineering is required.
Eric

[AMI Contracting]

In my AO half acre is minimum at 8' deep.
Depth matters as much as surface area.

[docjenser]

Let say for a 6 ton loopfield we use an area of 70x100 ft (0.16 acres) for heat exchange (slinky), why do we think that a much larger area is required for a pond, where a superior medium (water) connects the pipes to warmer ground (bottom of pond)? I have used 0.2 acres ponds 6ft deep, which work great. The key is to spread the pipe out similar to a horizontal slinky.

[thermopat]

Docjenser I think your logic is good. If I have a minimum of 8' deep and enough area for laying my slinky then why it would not work?

I think I will use 0.2 acres per 6 tons ratio.


AMI Contracting what is "AO" ? Thank you

[AMI Contracting]

Let say for a 6 ton loopfield we use an area of 70x100 ft (0.16 acres) for heat exchange (slinky), why do we think that a much larger area is required for a pond, where a superior medium (water) connects the pipes to warmer ground (bottom of pond)? I have used 0.2 acres ponds 6ft deep, which work great. The key is to spread the pipe out similar to a horizontal slinky.

True, less will do. I quoted manufacturer minimum requirement vs practical minimum. I would caution OP to know who they are dealing with if manufacturer minimums aren't complied with.

[Palace GeoThermal]

Let say for a 6 ton loopfield we use an area of 70x100 ft (0.16 acres) for heat exchange (slinky), why do we think that a much larger area is required for a pond, where a superior medium (water) connects the pipes to warmer ground (bottom of pond)? I have used 0.2 acres ponds 6ft deep, which work great. The key is to spread the pipe out similar to a horizontal slinky.

The OP is talking about using a very compact heat exchanger that I have very serious doubts about in a pond where there is no current.

[docjenser]

The OP is talking about using a very compact heat exchanger that I have very serious doubts about in a pond where there is no current.

I was thinking the same. Looking at the product, there are only a few openings where water can exchange. How would you prevent it from freezing up? At the end we are sending out fluids in the pipes at sub freezing temps.

In order to have a 6 ton capacity as claimed, and to support lets say 40.000 BTU/h heat extraction, and you assume that it is exposed to 39 degree water at the bottom of the pond, and the inside of the "ball" cannot be below 32 F, you need a minimum of 11.5 gallons per minute flow through the openings, under all the circumstances, pretty much through stratification inside the ball only. I don't see that happening.......

[urthbuoy]

Cold (liquid) water gets to around 35F around here.