The calculation and simulation software for heat pump systems

GeoT*SOL is a dynamic simulation program for professional planning, calculation and design of heat pump systems. Download your free 30-day trial now!



Are you looking for a user-friendly special tool for the planning and design of heat pump systems? Then our GeoT*SOL program is the perfect project partner for your design work.

You can choose between different heat sources (soil, air and groundwater) and modes of operation (monovalent, monoenergetic and bivalent) for your location. The integration of solar thermal systems and bivalent systems with boiler as heat generators should be emphasized. Requirements, losses and consumption are determined as a result of a dynamic minute simulation. Based on this, electricity consumption, seasonal heat performance factor and costs are calculated taking into account off-periods and tariffs. With these parameters, GeoT*SOL evaluates the economic efficiency of the system. The heat price and return are shown for the heat pump system and a comparison system.


Product highlights

More program details

Tariffs and blocking periods

Up to three blocking times can be set using the usual rules (intervals and limited duration) in order to be able to precisely depict the supply situation. Furthermore, the electricity price for the heat pump can be divided into high tariff (HT) and low tariff (NT).

Global climate data available

GeoT*SOL provides you with the latest TMY data of the DWD (current state 2017, averaging period 1995-2012) for Germany and more than 8,000 further climate locations for the whole world based on Meteonorm 7.3. You can use the interactive map to conveniently select the climate data. Locations not included are interpolated using satellite data and neighboring ground measuring stations. The import of your own measurement data takes place via files in DWD, Meteonorm or WBV format.

Configurable project report

The content can range from a short report with the annual performance figures to a detailed project report with diagrams and system components.

Profitability analysis

GeoT*SOL calculates the profitability according to the recommendation of the Federal Association of the Solar Industry (BSW) taking into account the funding: comparison of the costs of the heat pump system with a comparison system; capital value and production costs (heat price); modified internal rate of return (MIRR), profit taking into account the reinvestment.

Design heat pump systems and plan professionally


Designing custom heat pump systems is a complicated task that requires solar engineers to consider a variety of factors, including size and control of the system and the dimensioning of hot water tanks. GeoT*SOL helps you with this and can concentrate on the development of efficient and economical heat pump systems. All this is done through a practical and user-friendly interface.


Licensing and pricing


System requirements and releases

System requirements

  • Internet access
  • Operating systems: Windows 8.1, Windows 10
  • Free hard disk space: 400 MB
  • Microsoft .Net Framework 4.7.2 Redistributable Package (will be installed automatically)

Release notes

May 31st 2022GeoT*SOL 2021 Release 3

The following bugs have been fixed:

  • In some storage tanks, sensor heights were incorrect, so that they were not loaded (systems with buffer tanks for heating like HPS 7).
  • In standard storage tanks, the heat exchanger was not scaled when the volume was changed.
  • In the system HPS 8, the boiler delivered an incorrect supply temperature, so that the system ran in continuous DHW operation and the heating system was undersupplied.
January 31st 2022GeoT*SOL 2021 Release 2

The following new features and changes are included:

  • Update of the heat pump and storage database.
  • New climate data:
    • Meteonorm 8.1
    • PVGIS
    • Solcast

The following bugs have been fixed:

  • Error when updating the database.
  • In some storage tanks the collector connection height was wrong.
  • When using large heating buffer tanks, the hot water tank was not loaded correctly in system WPA 8.
  • In the evaluation of the heat pump according to the GEG, the annual performance factor was incorrectly used as a criterion.
  • Due to the mode of operation, the boiler in system WPA 7 did not run in summer.
June 21st 2021GeoT*SOL 2021 Release 1

The following new features and changes are included:

  • Longer pre-processing of the heat pump in parallel operation. As a result, the boiler starts later and the fraction of the heat pump in the generated energy is larger.
  • The window size of the program can be adjusted as desired. At the next start the program will be started with the last used dimensions.
  • The system selection page was updated (filter).
  • The database now includes over 600 tanks from well known manufactures. Tanks can now be configured or be selected from the database.
  • Display of the "Solar Keymark" certification for collectors.
  • Updated climate data based on Meteonorm 7.3.

The following bugs have been fixed:

  • The network license cannot be registered again.
March 27th 2020GeoT*SOL 2020 Release 1

The following new features and changes are included:

  • Calculation of heat pump performance factor updated due to new calculation guidelines (VDI guideline 4650, sheet 1, March 2019).
  • New bivalent heat pump system (HPS 8) with hydraulic switch and separate buffer tanks for space heating and domestic hot water.
  • Updated database with over 3,900 heat pumps (as of January 2020).

The following bugs have been fixed:

  • Incorrect simulation results when simulating systems with geothermal collectors.