CM: SAPHEA Geophires
Introduction
👉 Click here to access the online tutorial for this module
The SAPHEA GEOPHIRES Calculation Module (CM) is an integral part of the SAPHEA decision support toolbox, developed to support the planning and evaluation of geothermal district heating and cooling (geoHC) networks across Europe. It incorporates the GEOPHIRES (GEOthermal energy for Production of Heat and electricity Economically Simulated) techno-economic simulation model into the SAPHEA platform, enabling comprehensive assessments of geothermal energy systems.
Originally developed as a standalone simulation tool, GEOPHIRES estimates key project parameters such as capital and operational costs, energy production, and the levelized cost of energy (LCOE). Within the SAPHEA toolbox, it has been enhanced and tailored to:
- Simulate the direct use of hydro-geothermal resources for district heating applications
- Seamlessly integrate with the Hotmaps platform, allowing users to populate input parameters via a user-friendly interface
- Generate results in various formats—indicators, diagrams, and GIS layers—to support informed decision-making
- Enable scenario analysis, allowing users to modify input parameters and explore alternative geoHC development strategies
This module is designed to make geothermal project assessment more accessible, transparent, and adaptable to different regional contexts.
Input
This section describes the inputs, including basic and advanced input parameters of the CM.
Inputs
| Input Name | Unit | Default Value | Min Value | Max Value | Description |
|---|---|---|---|---|---|
| Reservoir Depth | km | 3 | 1.5 | 5.0 | Depth of the reservoir. |
| Gradient | degC/km | 30 | 0.0 | 500.0 | Temperature gradient with depth in the hydrothermal reservoir. |
| Number of Production Wells | 1 | 1.0 | 20.0 | Number of (identical) production wells. | |
| Number of Injection Wells | 1 | 1.0 | 20.0 | Number of (identical) injection wells. | |
| Production Flow Rate per Well | kg/s | 50 | 1.0 | 500.0 | Geofluid flow rate per production well. |
| Injection Temperature | degC | 40 | 0.0 | 200.0 | Constant geofluid injection temperature at injection wellhead. |
Basic Inputs
| Input Name | Unit | Default Value | Min Value | Max Value | Description |
|---|---|---|---|---|---|
| Productivity Index | kg/s/bar | 10 | 0.0 | 10.0 | Ratio of production well flow rate over inflow pressure drop. |
| Injectivity Index | kg/s/bar | 10 | 0.01 | 1000.0 | Ratio of injection well flow rate over outflow pressure drop. |
| Surface Temperature | degC | 10 | -50.0 | 50.0 | Surface temperature used for calculating bottom-hole temperature. |
| End-Use Efficiency Factor | 0.9 | 0.1 | 1.0 | Constant thermal efficiency of the direct-use application. | |
| Utilization Factor | 0.6 | 0.1 | 1.0 | Ratio of the time the plant is running in normal production in a year. | |
| Plant Lifetime | years | 30 | 1.0 | 100.0 | Lifetime of the geothermal plant. |
| EUR to USD Exchange Rate | 1.09 | 0.1 | 10.0 | Conversion rate from EUR to USD. | |
| Discount Rate | 0.04 | 0.0 | 1.0 | Discount rate used for LCOH calculation. |
Advanced Inputs
| Input Name | Unit | Default Value | Min Value | Max Value | Description |
|---|---|---|---|---|---|
| Reservoir Stimulation CapEx Adjustment Factor | 1 | 0.0 | 10.0 | Multiplier for reservoir stimulation capital cost correlation. | |
| Surface Plant CapEx Adjustment Factor | 1 | 0.0 | 10.0 | Multiplier for surface plant capital cost correlation. | |
| Field Gathering System CapEx Adjustment Factor | 1 | 0.0 | 10.0 | Multiplier for field gathering system capital cost correlation. | |
| Exploration CapEx Adjustment Factor | 1 | 0.0 | 10.0 | Multiplier for exploration capital cost correlation. | |
| Wellfield O&M Cost Adjustment Factor | 1 | 0.0 | 10.0 | Multiplier for wellfield operation & maintenance cost correlation. | |
| Surface Plant O&M Cost Adjustment Factor | 1 | 0.0 | 10.0 | Multiplier for surface plant operation & maintenance cost correlation. | |
| Water Cost Adjustment Factor | 1 | 0.0 | 10.0 | Multiplier for make-up water cost correlation. | |
| Electricity Rate | EUR/kWh | 0.1 | 0.01 | 10.0 | Price of electricity to calculate pumping costs. |
Output
Upon completion of a simulation, the SAPHEA GEOPHIRES module generates a comprehensive set of outputs that provide insights into the technical and economic performance of the geothermal system. These outputs are accessible through the SAPHEA platform and are also available for download in various formats.
Platform Indicators
Within the SAPHEA platform, key performance indicators (KPIs) are presented to offer a quick overview of the simulation results:
| Indicator | Unit | Description |
|---|---|---|
| LCOH | EUR/MWh_th | Levelized Cost of Heat, representing the average cost per megawatt-hour of thermal energy produced over the system's lifetime. |
| Drilling and Completion Costs | MEUR | Total capital expenditure associated with drilling and completing all production and injection wells. |
| Drilling and Completion Costs per Well | MEUR | Average cost for drilling and completing a single well, providing insight into individual well investments. |
| Stimulation Costs | MEUR | Costs related to enhancing the permeability of the reservoir, typically through hydraulic stimulation techniques. |
| Surface Power Plant Costs | MEUR | Capital costs for constructing the surface facilities required for energy conversion and distribution. |
| Field Gathering System Costs | MEUR | Expenses associated with the network of pipelines and equipment that transport geothermal fluids between wells and the surface plant. |
| Total Surface Equipment Costs | MEUR | Aggregate costs encompassing all surface installations, including the power plant and gathering systems. |
| Exploration Costs | MEUR | Investments made in geological surveys, drilling exploratory wells, and other activities to assess the geothermal resource. |
| Total Capital Costs | MEUR | The sum of all upfront investments required to develop the geothermal project, combining drilling, stimulation, surface equipment, and exploration costs. |
| Wellfield O&M Costs | MEUR/yr | Annual operation and maintenance expenses for the wellfield, including routine inspections, repairs, and monitoring. |
| Surface Plant O&M Costs | MEUR/yr | Yearly costs for operating and maintaining the surface power plant facilities. |
| Make-Up Water O&M Costs | MEUR/yr | Operational costs associated with sourcing and managing additional water required to compensate for losses in the system. |
| Average Annual Pumping Costs | MEUR/yr | Yearly expenses for the energy consumed by pumps to circulate geothermal fluids through the system. |
| Total Operating and Maintenance Costs | MEUR/yr | Combined annual O&M costs, providing a comprehensive view of the recurring expenses of the geothermal operation. |
| Bottom-Hole Temperature | °C | The temperature at the bottom of the production wells, indicating the quality of the thermal resource. |
| Average Production Well Temperature Drop | °C | The average decrease in temperature of the geothermal fluid as it travels from the reservoir to the surface, affecting energy conversion efficiency. |
| Average Pumping Power | MW_e | Mean electrical power required to operate the pumps, reflecting the energy input needed for fluid circulation. |
| Plant Outlet Pressure | kPa | The pressure of the geothermal fluid as it exits the surface plant, relevant for system design and safety considerations. |
| Production Wellhead Pressure | kPa | Pressure measured at the top of the production wells, important for monitoring well performance. |
| Average Injection Well Pump Pressure Drop | kPa | Average pressure loss encountered by the fluid as it is injected back into the reservoir, influencing pump sizing and energy requirements. |
| Average Production Well Pump Pressure Drop | kPa | Average pressure decrease experienced by the fluid as it is lifted from the reservoir to the surface, affecting pump performance and energy consumption. |
Additional Output Files
Beyond the platform indicators, the module generates supplementary output files that provide detailed information for further analysis:
-
Text Report (
.txt)
A comprehensive textual summary of the simulation inputs and outputs, including detailed breakdowns of costs, production figures, and economic metrics. -
Excel Report (
.xlsx)
A structured spreadsheet containing all relevant data, facilitating further analysis, visualisation, and integration with other tools.
These reports encompass detailed information such as:
-
Input Parameters
All user-defined and default input values used in the simulation. -
Production Profiles
Time-series data of heat production, reservoir temperatures, and flow rates. -
Cost Breakdown
Detailed CAPEX and OPEX components, including drilling, surface plant, and infrastructure costs. -
Economic Analysis
Calculation of Levelised Cost of Heat.
Sample Run
Step 1: Select the region
The current version of the SAPHEA GEOPHIRES CM does not retrieve data based on the selected region and solely works with the user-provided or default data. Therefore, the user can choose any region. In the upcoming production release, the surface temperatures will be retrieved from the respective layer based on the chosen region.
Please note that CMs will be deactivated and displayed in red if no region is selected.
Figure CM - SAPHEA GEOPHIRES: Selection of the working region (LAU2)
Step 2: Enter the input parameters
After selecting the region, users should click on the "Calculation Modules" tab located in the left pane. Next, click on "CM - SAPHEA GEOPHIRES" to display the input options.
The inputs are organized into several levels, ranging from the most basic to the most advanced. The first level of input parameters is referred to as "INPUTS," which consists of the fundamental input parameters. The full list of parameters in this category, along with their default, maximum, and minimum values and descriptions, can be found in Table: Inputs.
Figure CM - SAPHEA GEOPHIRES: Selection of the input parameters
Step 3: Enter the basic input parameters
After scrolling down in the inputs section, users will find the "Basic Inputs" category. This section includes a combination of expert-level parameters, such as productivity and injectivity indexes, as well as operational parameters like end-use efficiency and lifetime. The full list of parameters in this category, along with their default, maximum, and minimum values and descriptions, can be found in Table: Basic Inputs.
Figure CM - SAPHEA GEOPHIRES: Selection of the basic input parameters
Step 4: Enter the advanced input parameters
After further scrolling down in the inputs section, the user will find the "ADVANCED INPUTS: (LEVEL 1)" category. This section includes primarily cost adjustment factors. These parameters allow users to scale specific cost components — such as drilling, surface plant installation, or operation and maintenance — based on their own estimates or real-world cost data. By adjusting these factors, users can align the model's default cost function with their own cost structure, improving the accuracy and relevance of the results. The full list of parameters in this category, along with their default, maximum, and minimum values and descriptions, can be found in Table: Advanced Inputs.
Figure CM - SAPHEA GEOPHIRES: Selection of the advanced input parameters
Step 5: Run the CM and retrieve the results
Users can start the calculation by scrolling down to the bottom of the inputs section and clicking on the "RUN CM" button. The calculation should take only a few seconds. Then, a results tab will appear on the right-hand side of the screen. In this tab, the main indicators are displayed to offer a quick overview of the simulation results. The full list of indicators, alongside their units and descriptions, is available in Table: Platform Indicators.
Figure CM - SAPHEA GEOPHIRES: Indicators displayed on the platform
The users also have the option to export results. The buttons to export results are located at the bottom of the results section. There are two methods available for exporting the results:
- Exporting indicators
- By clicking the "EXPORT INDICATORS" button, users can export a CSV file consisting of the indicators displayed in the results section.
- Exporting detailed results
- By clicking the "EXPORT EXTRA FILES" button, users can download a ZIP file that contains four output files: two in XLSX format and two in TXT format. Both the XLSX and TXT files contain the same data. The TXT files are convenient for displaying results in a single tab, while the XLSX files are organized into multiple tabs, making it easy to copy and paste data for further analysis.
Figure CM - SAPHEA GEOPHIRES: Exporting results
Repository of the calculation module
You can access the open-source code for this calculation module here.
How To Cite
Ali Kök, in SAPHEA-Wiki, CM SAPHEA GEOPHRIES.
Authors And Reviewers
This page is written by Ali Kök EEG-TU Wien.
This page is reviewed by Ardak Akhatova e-think.
License
Copyright © 2025: Ali Kök
Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons CC BY 4.0 International License.
SPDX-License-Identifier: CC-BY-4.0
License-Text: https://spdx.org/licenses/CC-BY-4.0.html
Acknowledgement
We would like to convey our deepest appreciation to the HORIZON Europe Actions SAPHEA Project (Grant Agreement number 101075510), which co-funded the present investigation.