Hi Ben, it absolutely would be feasible if the stream is running all year round. The first thing to do here is calculate the flow rate. Basically what will happen is the pipework sunk within the stream will remove the heat from the water, so you need to ensure the flow rate is quick enough to replace the colder water – otherwise the set up won’t work.
We have a stream at the end of our home, it is not huge, but there seems to be a continous flow all year round. Would a water source heat pump be feasible? I guess since it is moving water that would help since the cold water would continously be replenished, but would it still provide us with decent heating in the winter? We have had solid wall insulation installed on our home via the GDHIF scheme and we are looking at putting a new insulated solid floor in.