Can anyone share experience/calculations for a closed loop laid into a stream, please?
Our contractor suggests digging a pond beside the stream and laying coils into the pond. I picture maintaining a pond, (i.e., removing silt, keeping out passersby, etc.) could require a lot more than having the loop(s) in the base of the stream under a layer of sizeable rocks (to keep the tubing from being dislodged during high water flows).
Experiences and opinions welcome, please!
Thank you!

Are you the guinnea pig for this or has the contractor done it before? Nothing wrong with being the guinnea pig as long as the cost allows for a complete do-over to another type of exchanger if the pig runs off. If you are not the pig, talk to the people who have it allready and ask about happiness and comfort.

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Eric Sackett
http://www.WeberWellDrilling.com
Delta P = 6 ATA

I'm drawn to the idea of exchanging heat with moving water...

However, the problem with moving water is that, well, it moves...sometimes a whole lot. What happens in that stream during 10 and 100 year flood events? Do trees, couches, bathtubs, propane tanks and every other manner of human and natural debris head downstream at a gallop, tearing up everything in their path?

Heavy stuff dragging along the bottom could shred geo loops no matter how well buried.

Are there permitting issues with dumping "Sizeable rocks" in the stream? Rocks weigh less when underwater and shift easily in high currents.

Conversely, does the stream ever dry out completely such as during a hot dry period? That could be a huge bummer for heat transfer at a time when you really need max cooling.

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Curt Kinder

www.hoviscustombuilders.com

Without data, you have but an opinion.
No thing done well is as simple as it seems

I'm glad you share my interest in moving water heat exchange!

Our stream never runs dry. During downpours it rises and flows vigorously, but we are near enough headwaters that debris is no problem. Currently it is at a summer low with good flow; typical flow is ~4x current; downpour flow is probably 100x current.

Permitting is a challenge we need to pursue. The Corps. of Engineers had to approve changes when the stream banks were improved.

Using the stream is my idea vs. the contractor's preference to dig a pond beside the stream.

I'm really anxious to learn of anyone else's experience using a steam vs. a pond, please!