GEOTHERMAL vs THERMAL ENERGY EXCHANGE AND STORAGE (TEES)

Conventional geothermal is considered a passive system as it was designed to either extract localized ground temperature energy or to dissipate waste energy.  It typically uses a single loop, can only flow in one direction, and the entire system is either on or off.  Geothermal borefields are usually designed in a linear configuration on with 10’ (3m) spacing between holes to reduce borehole interference.

TEES system is a dynamic geothermal borefield designed specifically to transfer hot and cold thermal energy to either the distribution system or stored in the ground.  It typically uses multiple loops, can inject, extract or store simultaneously, and can be managed down to a zone ring segment of a multi zone installation.  TEES borefields are usually designed in a circular configuration with variable spacing between holes to increase borehole interference, stored energy concentration, and minimize losses to the boundaries.

TEES TEMPERATURE OPERATING RANGE (yellow °C)

Thermal Energy Exchange and Storage (TEES) system is a critical component of a thermal microgrid and is used to manage load imbalances.  Functioning as a battery, heat exchanger and regulator the TEES systems are designed to meet the daily, seasonal and annual peak heating and cooling thermal requirements of community scale projects.. 

THERMAL ENERGY EXCHANGE AND STORAGE (TEES) SYSTEM DESIGN

 

TEES basic system functions are accomplished using two primary circuits - injection and extraction.  Based on the application each borehole will have one or two loops of each circuit in a borehole. 

 

The Injection Circuit can operate in the -20°C to 70°C range and is used to deliver hot or cold temperature water/ antifreeze solution to specific zones within the TEES system.  

 

The Extraction Circuit typically 5°C to 15°C is used to deliver tempered water to the distribution network and heat pumps. The cooler temperatures in this line allow the heat pumps to operate in both heating and cooling modes for year-round operation.