PhD scholarship in Scalable LLM-driven Semantic Digital Twins for Building Energy Modelling - DTU Construct

In collaboration with Chalmers University of Technology (Chalmers), the Technical University of Denmark (DTU) offers a new PhD position, “Scalable LLM-driven Semantic Digital Twins for Building Energy Modelling”. The PhD candidate will be supervised by supervisors from DTU and Chalmers. This project will integrate energy technology, building physics, HVAC systems, control systems architecture, semantic web technologies, advancing all the above disciplines.

The increasing availability of operational data and digital building information offers new opportunities for advancing building energy modeling beyond traditional case-by-case approaches. There is a growing need for modeling frameworks that can combine physical understanding with data-driven methods to support a wide range of energy system applications. Grid-interactive efficient buildings rely on emerging digital and cyber-physical systems to optimize HVAC operations for both energy efficiency and demand response. While Model Predictive Control (MPC) and Reinforcement Learning (RL) have proven effective in isolated studies, their widespread deployment is hindered by the lack of interoperability, the high cost of model creation, and data fragmentation.

This project seeks to overcome these barriers by integrating BIM-based energy modeling, semantic data models (Ontologies), and Large Language Models (LLM) into the control workflow. The candidate will explore how semantic digital twins can automate the generation of control-oriented models and how LLMs can facilitate natural language interaction with complex building management. 

The developed modeling framework will be designed to support multiple downstream applications, including energy flexibility assessment, advanced control strategies (e.g., MPC and RL), and evaluation of renovation and climate adaptation measures. Emphasis will be placed on robustness and scalability of the modeling approaches.

You will be part of a large global expert network under the IEA EBC Annex 96 - Grid Integrated Control of Buildings (https://annex96.iea-ebc.org).

Responsibilities and qualifications
The primary objective is to advance scalable modeling methodologies for building energy systems by combining physical modeling principles with data-driven techniques. The project addresses challenges related to model generalization, uncertainty, and applicability across diverse building types and energy system contexts.

You will:

• Develop robust control strategies that leverage semantic data structures for rapid deployment.
• Create workflows to bridge BIM, energy simulation engines (e.g., EnergyPlus, Modelica), and control algorithms.
• Investigate the use of LLMs as agents or interfaces for querying building data and optimizing control parameters.
• Validate methodologies using real-world data from built environment monitoring and living labs.
• Publish research findings in high-impact international journals and present at leading conferences.

The required selection criteria include:

• Domain Knowledge: Solid understanding of building physics, HVAC systems, and thermodynamics.
• Control Expertise: Experience with advanced control strategies and/or machine learning techniques.
• Digital Engineering Skills: Familiarity with Building Information Modeling (BIM) and energy modeling software.
• Data Science Proficiency: Knowledge of data modeling, ontologies (RDF/OWL), or semantic web technologies is highly desirable.
• Programming: Strong proficiency in Python, R, or MATLAB. Experience with Deep Learning frameworks (PyTorch, TensorFlow) and LLM APIs is an asset.
• Communication: Fluent English skills, both written and spoken, with a demonstrated ability to write scientific papers.

You will have the ability to work independently and collaboratively in interdisciplinary teams and strong analytical and critical thinking skills. Also, you have the motivation to work with complex systems and large datasets.

You must have a two-year master's degree (120 ECTS points) or a similar degree with an academic level equivalent to a two-year master's degree.

Approval and Enrolment 
The scholarship for the PhD degree is subject to academic approval, and the candidate will be enrolled in one of the general degree programmes at DTU. For information about our enrolment requirements and the general planning of the PhD study programme, please see DTU's rules for the PhD education. 

Assessment
The assessment of the applicants will be made by Associate Professor Rongling Li (DTU Construct) and Professor Angela Sasic Kalagasidis (Chalmers).

We offer
DTU is a leading technical university globally recognized for the excellence of its research, education, innovation and scientific advice. We offer a rewarding and challenging job in an international environment. We strive for academic excellence in an environment characterized by collegial respect and academic freedom tempered by responsibility.

Salary and appointment terms
The appointment will be based on the collective agreement with the Danish Confederation of Professional Associations. The allowance will be agreed upon with the relevant union. 

The period of employment is 3 years. The starting date is 1 June 2026 (can be negotiated based on mutual agreement).

You can read more about career paths at DTU here.

Further information
Further information may be obtained from Associate Professor Rongling Li, (https://orbit.dtu.dk/en/persons/rongling-li), DTU Construct. 

You can read more about Department of Civil and Mechanical Engineering at www.construct.dtu.dk.

If you are applying from abroad, you may find useful information on working in Denmark and at DTU at DTU – Moving to Denmark. Furthermore, you have the option of joining our monthly free seminar “PhD relocation to Denmark and startup “Zoom” seminar” for all questions regarding the practical matters of moving to Denmark and working as a PhD at DTU. 

Application procedure 
Your complete online application must be submitted no later than 22 April 2026 (23:59 Danish time). Applications must be submitted as one PDF file containing all materials to be given consideration. To apply, please open the link "Apply now", fill out the online application form, and attach all your materials in English in one PDF file. The file must include:

• A letter motivating the application (cover letter)
• Curriculum vitae 
• Grade transcripts and BSc/MSc diploma (in English) including official description of grading scale
• Documents showing relevant experience and skills (e.g., project report, publications, webpage)
• Contact information of two referees

You may apply prior to ob­tai­ning your master's degree but cannot begin before having received it. 

Applications received after the deadline will not be considered.

All interested candidates irrespective of age, gender, disability, race, religion or ethnic background are encouraged to apply. As DTU works with research in critical technology, which is subject to special rules for security and export control, open-source background checks may be conducted on qualified candidates for the position.

DTU Civil and Mechanical Engineering (DTU Construct) develops and utilises science and technical knowledge for the benefit of society and the sustainable development. We undertake research, education, innovation, and scientific advice of the highest quality within building design and processes, building construction and safety, building energy and services, solid mechanics, fluid mechanics, materials technology, manufacturing engineering, engineering design and thermal energy systems.

DTU – For the benefit of society since 1829
DTU is one of Europe's leading elite technical universities. Through research and education at an international top level, we create solutions to the major societal challenges of our time and help secure Europe's global leadership in sustainable technological development. Since Hans Christian Ørsted founded DTU almost 200 years ago, our mission has remained the same: We develop and create value through the natural and technical sciences for the benefit of society. DTU has 13,800 students, 1,600 PhD students, and 6,500 employees. We work in an international environment and have an inclusive, stimulating, and informal work culture. DTU has campuses in all parts of Denmark and in Greenland and collaborates with the best universities around the world.