Sustainable IT at WIM: Prof. Dr. Pooja Rani Conducts Research on “Green” Software Engineering
Well-programmed software today must do more than simply run smoothly: It should operate efficiently, conserve resources, and remain maintainable over the long term. With the increasing use of Artificial Intelligence and Large Language Models (LLMs) for automated code generation, an important question arises: How sustainable is the code generated by AI systems?
Prof. Dr. Pooja Rani, who has been Professor of Computer Science at the University of Mannheim since April 2026 and leads the Sustainable Software Engineering Group at WIM, is dedicated to this question. In a study conducted with her co-authors, she investigated how efficient software code generated by LLMs actually is. The study showed that even when the models are explicitly instructed to generate lean and energy-efficient code, they only rarely produce code that actually consumes less energy.
These findings highlight the importance of evaluating AI-generated code not only in terms of its functionality, but also its efficiency and resource consumption. Rani therefore advocates empirically grounded guidelines for “green” programming and greater awareness of sustainability among software developers.
For Rani, sustainability is a broad concept. In addition to energy consumption and the carbon footprint, she considers technical quality, reliability, maintainability, economic aspects, and social responsibility. Software should not only function efficiently, but also be maintainable over the long term and designed responsibly. This includes, for example, considering how software can be prevented from reinforcing prejudice or harming democratic processes.
At the University of Mannheim, a dedicated laboratory for software sustainability testing is being established as part of the professorship co-funded by the Wübben Stiftung Wissenschaft. Under strictly controlled hardware and software conditions, the laboratory will enable reliable and reproducible measurements – for example, of software energy consumption. The laboratory is intended to be unique within Germany and to contribute to building a robust empirical evidence base for sustainable software engineering.
Rani also brings her research into the classroom. Since the summer semester of 2026, she has been offering courses on sustainable software development. Her goal is to raise awareness of sustainability among software developers and to develop methods for more responsible software engineering based on empirical evidence.
Before joining the University of Mannheim in April 2026, Rani worked at the University of Zurich. She previously earned her doctorate at the University of Bern and gained industry experience, including in software quality assurance at Samsung. Today, she combines her experience in academia and industry in her work on sustainable and responsible software systems.
More about Prof. Dr. Pooja Rani
To learn more about how Pooja Rani went from growing up in an Indian village to pursuing a career in the high-tech world, why she has dedicated her research to sustainable software engineering, and what research she plans to pursue at the University of Mannheim, read the in-depth portrait by the Wübben Stiftung Wissenschaft.
To the portrait by the Wübben Stiftung Wissenschaft: “How can software become sustainable?”