FAQ on Geo-HEP Systems
Your questions about cooling, heating, and storage.
Questions and Answers About Geo-Hep Systems Solutions
How can buildings be efficiently cooled and heated? How can excess heat be stored for future use?
Geo-Hep-Systems’ solutions address different needs: The Geo-HEP high-performance energy pile uses the ground for heat exchange, while the seasonal storage system absorbs thermal energy in a specially designed, insulated tank and makes it available at a later time.
Here you’ll find answers regarding how both systems work, their potential applications, and planning considerations. We’d be happy to work with you to determine which solution is best suited for your project—based on your energy needs and on-site conditions.
How does the Geo-HEP system work?
The Geo-HEP system utilizes the relatively constant year-round temperatures of the ground for cooling, heating, and thermal storage. At its core is the high-performance energy pile, which features a specially designed heat transfer system.
During cooling, a circulating heat transfer medium absorbs heat from buildings, machinery, or technical processes. In the high-performance energy pile, this heat is first absorbed by the storage mass (preferably 43 m² of water) and then transferred to the surrounding ground via the pile wall.
Under suitable conditions, cooling occurs exclusively passively. In this case, electrical energy is required primarily for circulation pumps as well as measurement, control, and regulation systems. A continuously operating chiller is therefore no longer necessary.
For heating operation, the high-performance energy pile serves as the heat source for a heat pump. Of particular interest is the combined use: heat absorbed in the summer can be stored and later utilized for heating.
This allows cooling, heat supply, and thermal storage to be combined within a single system.
For which applications is the Geo-HEP system suitable?
The Geo-HEP system is particularly well-suited for applications requiring continuous cooling or simultaneous heating and cooling.
Typical applications include:
- Machine and process cooling
- Printing presses and production facilities
- Commercial, administrative, and manufacturing buildings
- Server rooms and data centers
- Heat supply via heat pumps
- Combination with photovoltaics, solar thermal, or other renewable energy sources
- Seasonal storage and time-shifted use of heat
The system can be used in both new construction and the retrofitting of existing heating and cooling systems. It is particularly cost-effective when there are high annual operating hours, continuous cooling demand, or limited space for geothermal probes.
Whether the Geo-HEP system is suitable for a project is determined on a case-by-case basis based on energy requirements, existing system technology, and site conditions.
What are the requirements for the subfloor?
It is not a specific type of soil or rock that is decisive, but rather the subsurface’s ability to absorb, store, and release heat.
During the planning phase, the following factors, among others, are examined:
- The structure and stratification of the subsoil
- Thermal conductivity and heat storage capacity
- Strength and drillability
- Groundwater conditions
- Permissible drilling depth
- Distances from buildings and utility lines
Based on a geological and, if necessary, hydrogeological site assessment, the achievable output per high-performance energy pile as well as the required number of energy piles are determined.
Geological conditions influence not only the technical performance but also the project’s approvability and economic viability.
Is the presence of groundwater an advantage?
Yes, the performance of the Geo-HEP system is significantly influenced by the hydrogeological conditions at the site. The flow velocity of the groundwater plays a particularly crucial role in passive cooling.
Moving groundwater continuously carries away the heat injected into the subsurface. This thermally regenerates the area around the high-performance energy pile and reduces heat buildup in the rock.
The higher the natural flow velocity of the groundwater, the greater the continuous heat dissipation tends to be. This significantly increases the cooling capacity of the Geo-HEP system, particularly in passive cooling mode, and guarantees consistently high heat transfer rates.
The Geo-HEP system operates as a closed heat exchange system. The groundwater is neither pumped nor does it form part of the system’s circulation loop. It serves exclusively as a natural heat carrier in the subsurface.
Therefore, the following hydrogeological parameters, among others, are examined when designing a Geo-HEP system:
- Groundwater flow velocity
- Flow direction
- Thickness of the aquifers
- Permeability of the bedrock
- Groundwater level and seasonal fluctuations
These site parameters have a significant influence on the achievable cooling capacity, the number of high-performance energy piles required, and the cost-effectiveness of the overall system.
Can the Geo-HEP system be used in water protection areas?
Use is generally possible, but must be evaluated on a case-by-case basis for each location.
Approval depends in particular on
- the protected area zone,
- local groundwater conditions,
- the drilling depth,
- the sealing concept, secure sealing of the borehole,
- a sealed system design
- heat transfer medium used
- Protection against leaks
- Prevention of a connection between different groundwater levels
- Drilling depth and geological structure
- Requirements of the local water management authority
.
The sealed design of the Geo-HEP system generally provides a good foundation. However, each permit is granted solely on a case-by-case basis.
We therefore recommend involving the responsible water authority early in the planning phase.
How energy-efficient is the Geo-HEP system?
Cost-effectiveness is calculated individually for each project.
Factors taken into account include:
- historical energy consumption
- Operating hours
- required heating and cooling capacity
- Maintenance and repair costs
- Pump energy
- Capital costs
- Funding opportunities
- Expected energy prices
- CO2 tax per metric ton
In a documented reference project for cooling printing presses, the annual cooling energy costs were reduced from over 30,000 euros to approximately 156 euros in pump electricity. This corresponds to a savings of 99.48%; this result was verified by DENA and awarded the Best Practice Label for energy efficiency.
This result applies exclusively to this project and does not constitute a general guarantee of savings.
For each project, we prepare an individual profitability and payback analysis.
What savings are possible?
Cost-effectiveness is calculated individually for each project.
Factors taken into account include:
- historical energy consumption
- Operating hours
- required heating and cooling capacity
- Maintenance and repair costs
- Pump energy
- Capital costs
- Funding opportunities
- Expected energy prices
- CO2 tax per metric ton
In a documented reference project for cooling printing presses, the annual cooling energy costs were reduced from over 30,000 euros to approximately 156 euros in pump electricity. This corresponds to a savings of 99.48%; the project was reviewed by DENA and awarded the Best Practice Label for energy efficiency.
This result applies exclusively to this project and does not constitute a general guarantee of savings.
For each project, we prepare an individual economic feasibility and payback analysis.
Is the Geo-HEP system eligible for funding?
Yes, depending on the intended use and system design, the Geo-HEP system may be eligible for funding.
For businesses, for example, programs offered by KfW or BAFA may be applicable. Eligible items may include heat pumps, thermal storage systems, components for free cooling, and control and regulation technology.
Whether and to what extent funding is available must be verified before the project begins.
Note: Funding programs and subsidy rates are subject to change. The funding conditions in effect at the time of application are decisive.
Information current as of: July 2026.
Can the Geo-HEP system heat and cool at the same time?
Yes. The Geo-HEP system can be used for both cooling and heating.
In the summer, excess heat from buildings or production processes is transferred into the ground. During the heating season, this stored heat can be reused—depending on the system design.
This can be particularly cost-effective when there is a simultaneous need for both cooling and heating, such as in industrial or office buildings.
The optimal operating mode is designed on a project-by-project basis based on the annual heating and cooling profiles.
Will it also be possible in the future to use a seasonal heat storage system for largely passive heating?
Yes, Geo-HEP Systems is currently developing solutions for the seasonal storage of excess heat.
For example, heat from summer building cooling, industrial processes, or solar thermal systems can be stored underground and reused later.
Whether fully passive heating is possible depends on the temperature level reached in the storage system as well as on the building’s heating system.
If the storage temperature is insufficient, a heat pump can efficiently raise the available heat to the required temperature level.
The seasonal storage system can also be used as a cold storage system, particularly when there are very high cooling demands, such as in data centers.
How does the Geo-HEP system differ from traditional geothermal systems?
While traditional geothermal probes primarily serve as a heat source and conventional energy piles are often used solely as a component of the foundation, the Geo-HEP system combines multiple functions in a single high-performance energy pile.
Traditional Geothermal Energy | Geo-HEP System |
Heat source | Heat source, cooling, and thermal storage |
Slim probe | Large-Volume, High-Performance Energy Pile |
Low storage mass | Integrated thermal storage mass |
Limited heat transfer surface area | Large heat exchange surface area |
No targeted load buffering | Storage of short-term load peaks |
Primarily used for heating | Cooling, heating, and storage operation in a single system |
Components in the borehole | Technical components accessible for maintenance |
Depending on the project, this results in the following advantages in particular:
- High heat exchange with a comparatively small footprint
- thermal storage of excess energy
- passive cooling with low power consumption
- Use as a heat source for heat pumps
- Integration into existing heating and cooling systems
- Combined cooling, heating, and storage operation
- Low-maintenance design
The benefits that can be achieved in each specific case depend on the required capacity, the load profile, user behavior throughout the year, geological conditions, and the existing system infrastructure.
Do you have any further questions about our solutions?
We’d be happy to send you more information and references or schedule a personal meeting.