Hi there, I have been investigating the heat sink system aka Geothermal heat rejection.
is there anyone out there who has done it before? I have got theoretical evidences that it can be done.

I'm doing it right now. I have a large heat sink in my back yard and I'm pumping heat in to it or out of it almost every day. I think most of the people on this forum are, too. Some of them have actual data for evidence.

Can i assume that u are doing an horizontal loop. U will locate the coil around 6 fts below grownd depending on where u find that constant temperature below ground.
Do u still have a cooling tower, or u have litteraly replaced ur cooling tower.
Thank u!

Several horizontal loops, 8ft. deep. I have never seen a cooling tower used for residential cooling or heating. This system is 15 yrs. old and is (more or less) the same as thousands of other residential geo-thermal heat pump systems in use.

paul was there a specific product or design you were asking about?
"Heat sink" as a generic term. In this context it could describe virtually any system that's not a pump and dump.
Joe

It is going to be my very first time to do a geothermal heat rejection which I called heat sink system.
It is for an office building which is attached to a residential building. the heat load rises to 1.7 MW. The cooling tower plant rrom is located on top of the office building(6 floors), my residential building has got 10 floors, I am trying to avoid moisture, noises,...by using the geothermal system.

For such a system you will almost certainly require design and install assistance far beyond what we render here