Has anyone ever heard of anyone having a desuperheater hooked up to a hybrid water heater?

We have that set up with a storage tank in-between the two.

I am wondering if there would be any cost savings since the water would already be heated partially from the desuperheater when the geothermal is in use.

Yes, there should be some cost savings. However, our house is extremely energy efficient, so our geothermal does not run as often as it would if the house was not as energy efficient. Therefore, we don't get as much of that savings as others would get.

What brand hybrid hot water heater did you have installed?

We are looking at the Ge geospring because we get a discount and also get a rebate on it with our appliance purchase if I time the purchase right.

AO Smith

Yes, there will be cost savings and most of that is going to be in the summer when the geothermal is producing excess heat to cool the house. A desuperheater basically heats water for free in the summer by salvaging the heat that would otherwise be dumped into the ground. ThatâÂÂs going to be more efficient that the regular heat pump water heater, which needs to use some electricity to keep the compressor and fan running.
There is a possibility, though, that it will not save any money in winter because the geothermal works as a heater at that time and you will transfering heat from one heat pump heater to another. It could a good idea to deactivate the desuperheater in the winter to see if there is a significant change and perhaps permanently shut it down until spring if you find out it is not saving anything.
Even if it doesnâÂÂt make a difference in the winter, it is worth installing the desuperheater for the decent savings during summer.