Factors Affecting the Type of GHP Loop

Geothermal heat pumps (GHPs) can be used effectively almost anywhere in the country. However, the specific geological, hydrological, and spatial characteristics of a site determine the best type of ground loop for a specific location.

Instructions: Click on the hot spots in the image below to view the factors affecting the type of GHP Loop.

Factors Affecting the Type of GHP Loop.

  • Horizontal ground loops (generally the most economical) are typically used for newly constructed buildings with sufficient land.
  • Vertical installations or more compact, horizontal, Slinky installations are often used for existing buildings because they minimize the disturbance to the landscape, existing underground utilities, and sprinklers systems.
  • Ground water can also be used as a source for open loop systems, provided the water quality is suitable and all ground water discharge regulations are met.
  • The depth, volume, and water quality of bodies of surface water determine if the water will be used as an open-loop system or as a repository for coils of piping in a closed-loop system.
  • The amount of soil available — areas with extensive hard rock or with soil too shallow to trench may install vertical ground loops instead of horizontal loops.
  • The composition and properties of the soil and rock impact heat transfer rates. Soil with good heat transfer properties requires less piping to gather a certain amount of heat than soil with poor heat transfer properties.
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