The heat source for a water source heat pump is water from sources like lakes, ponds, rivers, aquifers, or even mine water. The heat pump absorbs energy from these water sources.
Understanding Water Source Heat Pumps
Water source heat pumps (WSHPs) operate on the principle of transferring heat rather than generating it. They utilize the relatively stable temperature of water bodies to either heat or cool a building. While they share similarities with ground source heat pumps, the key difference lies in their heat source and method of heat extraction.
Water Sources Used
Here's a breakdown of common water sources:
- Lakes and Ponds: Large bodies of water provide a consistent temperature source. Submerged pipework is used to extract heat.
- Rivers: Similar to lakes and ponds, rivers offer a readily available heat source, but considerations for water flow and potential environmental impact are important.
- Aquifers: These underground layers of permeable rock or sediment that hold groundwater can provide a stable temperature source.
- Mine Water: In areas with abandoned mines, the water that fills these mines can be used as a heat source.
How it Works
- Submerged Pipework: A network of pipes is submerged in the water source.
- Heat Transfer: A heat transfer fluid (usually water mixed with antifreeze) circulates through the pipes. This fluid absorbs heat from the water source in winter or rejects heat to the water source in summer.
- Heat Pump Unit: The heat transfer fluid then carries this heat to the heat pump unit inside the building.
- Heating or Cooling: The heat pump either compresses the fluid to increase its temperature for heating or uses a refrigerant cycle to cool the building.
Advantages of Water Source Heat Pumps
- Efficiency: Water's higher thermal conductivity compared to air or soil makes WSHPs highly efficient.
- Stable Temperatures: Water sources maintain relatively stable temperatures year-round, improving performance.
- Environmentally Friendly: Reduces reliance on fossil fuels.
