Geothermal & Hydronic Energy Sources
The GHT pre-conditioning system requires a thermal source to transfer natural or generated energy to the ventilation air. Choose from traditional ground loops or integrate directly with modern heat pump hydronics.
Horizontal Ground Collectors
An essential and highly cost-effective component installed beneath the ground surface. Ideal for properties with ample open land space.
Key Specifications
- Installation Depth: Typically 1.5 to 2.5 meters (4.9 to 8.2 ft), up to a maximum of 5 meters (16.4 ft).
- Pipe Spacing: Minimum distance between PE-pipes must be 0.8 meters (2.6 ft).
- Longevity: Virtually unlimited lifespan with minimal to zero maintenance required.
Advantages
- ✔ Significantly reduced installation costs
- ✔ Excellent for loamy/moist soils
- ✔ Highly eco-friendly operation
Vertical Boreholes
Involves drilling deep into the ground to access highly stable underground temperatures. The perfect compact solution for areas with limited land space.
Key Specifications
- Installation Depth: 50 to 200 meters (164 to 656 ft), depending on soil and geological conditions.
- Efficiency: Deeper layers provide extremely stable and efficient heat exchange temperatures.
- Footprint: Requires almost no surface area post-installation.
Advantages
- ✔ Consistent yield regardless of surface seasons
- ✔ Ideal for dense urban or commercial projects
- ✔ Maximum thermal efficiency per foot/meter
Integrating with Existing HVAC Plants
GHT modules do not always require a dedicated, standalone ground loop. They are engineered to seamlessly connect directly to a building's primary heating and cooling systems, offering two highly efficient integration methods depending on the setup.
Shared Geothermal Loops
If the property already utilizes a Geothermal Heat Pump, the GHT unit can be connected directly to the same primary ground loop.
During summer, the GHT unit cools hot outdoor air, transferring the extracted heat into the glycol. Pumping this warm glycol back underground actively regenerates the soil's thermal mass. This prevents long-term soil depletion (permafrost effect) and helps raise the baseline ground temperature. Higher source temperatures directly translate to an improved Seasonal Performance Factor (SPF) and higher COP for the main heat pump during the winter heating season.
Air-to-Water Buffer Tanks
If drilling a ground loop is not feasible, GHT units integrate flawlessly into Air-to-Water heat pump systems via a standard hydronic buffer tank.
- Direct Feed: Receives unmixed fluid directly from the buffer tank (e.g., 10°C / 50°F in summer, 52°C / 125°F in winter).
- Crucial Freeze Protection: In cold climates, pure water cannot be routed to the intake air coil. A glycol solution (or an intermediate plate heat exchanger separating the tank's water from the GHT glycol loop) must be used to prevent coil bursting during circulation pauses.
- Hybrid Staging: Acts as 2nd stage heating and primary summer air cooling.
- Precise Control: Managed by standard zone circulators and thermostats.
Critical Engineering Guidelines
🌱 Soil Types & Groundwater
Compact, loamy soils transfer significantly more heat to the brine than loose, sandy soils. If the pipe is located below the groundwater level, the energy absorption increases drastically. For sandy soils, the calculated pipe length may need to be doubled.
📏 Pipe Length Calculation
Only the length of the PE-pipes physically buried in the ground should be considered when calculating total energy absorption. Pipes routed inside the building do not contribute to heat transfer and should be excluded from thermal calculations.
⚙️ System Integration
The highest point of the brine circuit must be the vent of the brine-defroster's float vent. Additionally, in many scenarios, an existing ground-source heat pump's primary brine circuit can be utilized simultaneously as the energy source for the GHT unit.