GHEtool 2.1.0

Python package for borefield sizing

GHEtool: An open-source tool for borefield sizing in Python

What is GHEtool?

GHEtool is a Python package that contains all the functionalities needed to deal with borefield design. It is developed for both researchers and practitioners. The core of this package is the automated sizing of borefield under different conditions. The sizing of a borefield is typically slow due to the high complexity of the mathematical background. Because this tool has a lot of precalculated data (cf. infra), GHEtool can size a borefield in the order of tenths of milliseconds. This sizing typically takes the order of minutes. Therefore, this tool is suited for being implemented in workflows where iterations are required.

Read The Docs

GHEtool has an elaborate documentation were all the functionalities of the tool are explained, with examples, literature and validation. This can be found on GHEtool.readthedocs.io.

Graphical user interface

GHEtool also comes with a graphical user interface (GUI). This GUI is prebuilt as an exe-file (only for Windows platforms currently) because this provides access to all the functionalities without coding. A setup to install the GUI at the user-defined place is also implemented and available at https://GHEtool.sysi.be.

Screenshot of the GUI.

Requirements

This code is tested with Python 3.8 and requires the following libraries (the versions mentioned are the ones with which the code is tested)

• Numpy (>=1.20.2)
• Scipy (>=1.6.2)
• Matplotlib (>=3.4.1)
• Pygfunction (>=2.2.1)
• Openpyxl (>=3.0.7)
• Pandas (>=1.2.4)

For the GUI

• PyQt5 (>=5.10)

For the tests

• Pytest (>=7.1.2)

Quick start

Installation

One can install GHEtool by running Pip and running the command

pip install GHEtool

or one can install a newer development version using

pip install --extra-index-url https://test.pypi.org/simple/ GHEtool

Developers can clone this repository.

It is a good practise to use virtual environments (venv) when working on a (new) Python project so different Python and package versions don't conflict with eachother. For GHEtool, Python 3.8 is recommended. General information about Python virtual environments can be found here and in this article.

Check installation

To check whether everything is installed correctly, run the following command

pytest --pyargs GHEtool

This runs some predefined cases to see whether all the internal dependencies work correctly. All test should pass successfully.

Get started with GHEtool

To get started with GHEtool, one needs to create a Borefield object. This is done in the following steps.

from GHEtool import Borefield, GroundData

After importing the necessary classes, one sets all the relevant ground data and borehole equivalent resistance.

data = GroundData(3,   # ground thermal conductivity (W/mK)
                  10,  # initial/undisturbed ground temperature (deg C)
                  0.2, # borehole equivalent resistance (mK/W)
                  2.4*10**6) # volumetric heat capacity of the ground (J/m3K) 

Furthermore, one needs to set the peak and monthly baseload for both heating and cooling.

peak_cooling = [0., 0, 34., 69., 133., 187., 213., 240., 160., 37., 0., 0.]   # Peak cooling in kW
peak_heating = [160., 142, 102., 55., 0., 0., 0., 0., 40.4, 85., 119., 136.]  # Peak heating in kW

monthly_load_heating = [46500.0, 44400.0, 37500.0, 29700.0, 19200.0, 0.0, 0.0, 0.0, 18300.0, 26100.0, 35100.0, 43200.0]        # in kWh
monthly_load_cooling = [4000.0, 8000.0, 8000.0, 8000.0, 12000.0, 16000.0, 32000.0, 32000.0, 16000.0, 12000.0, 8000.0, 4000.0]  # in kWh

Next, one creates the borefield object in GHEtool and sets the temperature constraints and the ground data.

# create the borefield object
borefield = Borefield(simulation_period=20,
                      peak_heating=peak_heating,
                      peak_cooling=peak_cooling,
                      baseload_heating=monthly_load_heating,
                      baseload_cooling=monthly_load_cooling)

borefield.set_ground_parameters(data)

# set temperature boundaries
borefield.set_max_ground_temperature(16)  # maximum temperature
borefield.set_min_ground_temperature(0)  # minimum temperature

# set a rectangular borefield
borefield.create_rectangular_borefield(10, 12, 6, 6, 110, 4, 0.075)

Note that the borefield can also be set using the pygfunction package.

import pygfunction as gt

# set a rectangular borefield
borefield_gt = gt.boreholes.rectangle_field(10, 12, 6, 6, 110, 1, 0.075) 
borefield.set_borefield(borefield_gt)

Once a Borefield object is created, one can make use of all the functionalities of GHEtool. One can for example size the borefield using:

depth = borefield.size(100)
print("The borehole depth is: ", depth, "m")

Or one can plot the temperature profile by using

borefield.print_temperature_profile(legend=True)

A full list of functionalities is given below.

Functionalities

GHEtool offers functionalities of value to all different disciplines working with borefields. The features are available both in the code environment and in the GUI. For more information about the functionalities of GHEtool, please visit the ReadTheDocs.

License

GHEtool is licensed under the terms of the 3-clause BSD-license. See GHEtool license.

Contributing to GHEtool

You can report bugs and propose enhancements on the issue tracker. If you want to add new features and contribute to the code, please contact Wouter Peere ([e-mail]).

Main contributors

Wouter Peere, KU Leuven & boydens engineering (part of Sweco), [e-mail]

Tobias Blanke, Solar-Institute Jülich, FH Aachen, [e-mail]

Citation

Please cite GHEtool using the JOSS paper.

Peere, W., Blanke, T.(2022). GHEtool: An open-source tool for borefield sizing in Python. Journal of Open Source Software, 7(76), 4406, https://doi.org/10.21105/joss.04406

For more information on how to cite GHEtool, please visit the ReadTheDocs at GHEtool.readthedocs.io.

References

Development of GHEtool

Peere, W., Blanke, T. (2022). GHEtool: An open-source tool for borefield sizing in Python. Journal of Open Source Software, 7(76), 4406, https://doi.org/10.21105/joss.04406

Peere, W., Picard, D., Cupeiro Figueroa, I., Boydens, W., and Helsen, L. (2021) Validated combined first and last year borefield sizing methodology. In Proceedings of International Building Simulation Conference 2021. Brugge (Belgium), 1-3 September 2021. https://doi.org/10.26868/25222708.2021.30180

Peere, W. (2020) Methode voor economische optimalisatie van geothermische verwarmings- en koelsystemen. Master thesis, Department of Mechanical Engineering, KU Leuven, Belgium.

Applications/Mentions of GHEtool

Peere, W., Boydens, W., Helsen, L. (2022). GHEtool: een open-sourcetool voor boorvelddimensionering. Presented at the 15e warmtepompsymposium: van uitdaging naar aanpak, Quadrivium, Heverlee, België.

Peere, W., Coninx, M., De Nies, J., Hermans, L., Boydens, W., Helsen, L. (2022). Cost-efficient Cooling of Buildings by means of Borefields with Active and Passive Cooling. Presented at the 15e warmtepompsymposium: van uitdaging naar aanpak, Quadrivium, Heverlee, België.

Peere, W. (2022). Technologieën voor de energietransitie. Presented at the Energietransitie in meergezinswoningen en kantoorgebouwen: uitdagingen!, VUB Brussel Bruxelles - U Residence.

M. Sharifi. (2022) Early-Stage Integrated Design Methods for Hybrid GEOTABS Buildings. PhD thesis, Department of Architecture and Urban Planning, Faculty of Engineering and Architecture, Ghent University.

Coninx M., De Nies J. (2022) Cost-efficient Cooling of Buildings by means of Borefields with Active and Passive Cooling. Master thesis, Department of Mechanical Engineering, KU Leuven, Belgium.

Michiels E. (2022) Dimensionering van meerdere gekoppelde boorvelden op basis van het type vraagprofiel en de verbinding met de gebruikers. Master thesis, Department of Mechanical Engineering, KU Leuven, Belgium.

Vanpoucke B. (2022) Optimale dimensionering van boorvelden door een variabel massadebiet. Master thesis, Department of Mechanical Engineering, KU Leuven, Belgium.

Haesen R., Hermans L. (2021) Design and Assessment of Low-carbon Residential District Concepts with (Collective) Seasonal Thermal Energy Storage. Master thesis, Departement of Mechanical Engineering, KU Leuven, Belgium.