PhD Position on Global Potential of Subsurface Geothermal Heat Recycling

We are seeking a PhD student to investigate the Global Potential of Shallow Subsurface Geothermal Heat Recycling, including projected changes caused by ongoing climate change and urbanization.

Special focus will be on the analysis of feasibility with three key questions:

  • where is it technically feasible to recycle accumulated waste heat in the urban underground?
  • where is it economically feasible to recycle accumulated waste heat in the urban underground?
  • who might benefit from it?

You will be part of a newly formed junior research group at the Institute of Photogrammetry and Remote Sensing (IPF) at the Karlsruhe Institute of Technology (KIT) and join (together with two other PhD students and a Postdoc) the project Large scale assessment of the effects of sustainable heat recycling in the shallow subsurface on above ground temperatures funded through the Volkswagen foundation.

The Project:

Urban overheating and a sustainable energy supply are two of the most important challenges of our time. More than 50% of the global population lives in cities and is therefore exposed to a climate shaped by the built environment. In most regions of this planet so-called urban heat islands dominate temperatures, which can threaten the health, general well-being, and productivity of local populations. At the same time, European households use more than 80% of their total energy consumption for space and water heating. Conventional methods are primarily based on fossil fuels.

While both topics are so far only considered separately, they are linked via the urban underground. Here, like above ground, temperatures are elevated representing the accumulated waste heat of the city. This waste heat can be accessed and recycled though shallow geothermal systems. Local model calculations indicate that the accumulated thermal energy often significantly exceeds the annual local space heating demand. However, there is a lack of large-scale studies, and the link between the thermal regime of the subsurface and the urban climate above ground has so far been disregarded.

This groundbreaking interdisciplinary project will combine social sciences, geo-science, and urban climatology with geospatial data science to answer the question: Can sustainable heat recycling in the subsurface help mitigate urban heat locally? This will be answer for Germany, and partially even globally, at a sub-city scale.

To meet this objective, we need to understand the fundamental mechanics linking the demand for space and water heating, the potential for heat recycling, and urban heat islands to each other. Urban heat increases the potential for heat recycling but decreases our heating demand. Heat recycling on the other hand is a sustainable source for space and water heating and can reduce subsurface temperatures. What is left to answer, are three distinct research questions:

  1. How do subsurface temperatures impact urban climate?
  2. What is the local potential for subsurface heat recycling?
  3. What is the local current and future heating demand?

Your Tasks:

You will be answering the research question "What is the local potential for subsurface heat recycling?". Supported by researchers at the Institute of Applied Geosciences (AGW) at KIT, you will use tools of geospatial data science to map the global feasibility of shallow geothermal heat recycling. Your work will build on top of studies such as our recent article on shallow subsurface heat recycling in Nature Communications or a case study for heat recycling in Vienna, Austria.

During your PhD you will gain skills and experience in

  • big geodata analysis in python and/or GIS
  • processing of satellite data
  • geospatial data processing and visualization in google earth engine
  • presenting your work to an academic and lay audience
  • publishing your work in international scientific journals


You must hold a master's degree in a discipline of relevance (e.g., geo sciences, environmental science, geography or others) and be willing to relocate to Karlsruhe, Germany. While German language skills are encouraged, they are not required. However, English language skills are expected. Ideally you are a creative, yet analytically thinking individual with a thirst for knowledge who values a diverse workplace.

Beneficial experience and qualities include:

  • Interest and/or experience in topics relevant to the project (e.g., geothermal energy, sustainable energy)
  • Interest and/or experience in geospatial data science and statistical analysis
  • (Willingness to acquire) skills in python or a comparable program such as R or MATLAB
  • (Willingness to acquire) skills in google earth engine or comparable programs to create interactive maps
  • Interest in trans- and interdisciplinary research.

What we offer:

We offer a 3+1 year contract. During your PhD (3-years) you will be paid 75% of the Collective Agreement for the German Public Service Sector (TV-L EG13). Should you decide to stay longer we may offer a 4th year at 100%.

You will join the PhD program of the KIT-Department of Civil Engineering, Geo and Environmental Sciences (BGU) where you have the option to complete your PhD as a cumulative thesis.

You are also encouraged to participate in GRACE, the Graduate School for PhD students of the KIT-Center Climate and Environment. It is the goal of GRACE to provide to its students not only highly specialized and interdisciplinary knowledge but also important key skill qualifications. GRACE also offers scholarships to PhD students for a 3-month long research stay abroad.

Furthermore, you will have access to a wide range of courses for professional development offered through the Karlsruhe House of Young Scientist (KHYS).

The University:

You will be part of a newly formed junior research group at the Institute of Photogrammetry and Remote Sensing (IPF) located at the main campus of the Karlsruhe Institute of Technology (Campus Süd), right next to the 300-year-old Karlsruhe Palace. IPF combines competence in computer vision, remote sensing, geoinformatics, and active sensing and is therefore the perfect home for an interdisciplinary project using methods of large-scale geospatial data analysis. You will be the fourth member of a growing, multi?disciplinary, highly collaborative, and young team, well connected to national and international research networks and activities. We offer you an attractive and modern workplace with access to the excellent equipment of the KIT, a varied work, a wide range of training opportunities, flexible working time models, an allowance for the job ticket BW and a casino/cafeteria.

How to apply:

If you are interested, please send your application including a cover letter, your CV, and all certificates/diplomas in electronic form to Dr. Susanne Benz (email: by March 19, 2023. You may also contact her with any further questions.

posted: 21 February 2023    Please mention EARTHWORKS when responding to this advertisement.