Water sources have long been regarded as a means to produce affordable and secure heating from a renewable energy source. Especially the larger homes and commercial properties that are in close proximity to a water source like canals, rivers and lakes can access and extract heat energy from the water at a much lower cost than traditional ground collectors and other alternative forms of heating.



Underfloor heating with water source heatpumps 


The open loop ground source heatpump is connected to the submerged pipework in the body of the water and absorbs the heat energy nfrom its surroundings in the same way as it would if burried in the ground. The difference is that water is an excellent conducter of heat and is especially efficient for heat extraction in combination with underfloor heating.


What makes water a good source for ground source heatpumps?

    • the heattransfer rate from water is higher than that in the ground


    • the water is in close contact with all of the pipe at the times enhancing its efficiency


    • the circulation of water provides constant energy replacement


    • the use of a water source removes the need for digging or drilling, reducing the cost and duration of the installation


    • teh return temperature to the heat pump is generally 5-6 degrees higher than ground collections, increasing the efficiency of the heat pump


Water sources offer different considerations for the end user:

    • Lakes: the number of pipe mats needed depend on the size of the heatpump as well as the size of the body of water. In addition to this it depends on how that body is fed


    • streams and rivers are ideal for water source heat pumps if not too small or too shallow. In case of large nrivers, an open loop system could be considered drawing the water directly from the river and putting it through the heat pumps’s evaporator heat exchanger. A second plate heat exchanger as an intermediary is recommended to overcome risks of corrosion and filtration.


    • sea water: both open and closed loop systems are possible. Due to sea water’s corrosive properties, specialist titanium heat exchengers must be used.

Other ground souce heat pumps for underfloor heating systems but also air source heatpumps can be found via the link below.