Thesis Work - Security Analysis in Nuclear Power

Vattenfall AB · Full-time

Uppsala, Sweden

Company Description Vattenfall is a leading European energy company with 12 million customers and approximately 21,000 employees. We are convinced that there is a path to building a future where everyone can choose fossil-free ways to transport, produce, and live. About the Role Are you a student who wants to use your knowledge to contribute to real solutions within the energy transition? With us, you have the opportunity to complete your thesis work close to operations, working alongside experienced specialists on challenges where your ideas and perspectives can make a difference. This thesis work is conducted within Vattenfall Nuclear Fuel, where you will perform a Security Analysis in nuclear power - Analysis of the falling control rod event from a different perspective. Vattenfall Nuclear Fuel is part of Vattenfall Power Solutions and is responsible for ensuring nuclear fuel supply and fuel management services to our nuclear power plants, with a focus on safety and sustainability. This thesis work is conducted within the Safety Analysis unit. In this thesis work, you will perform a safety analysis of the reactivity event falling control rod, but in reverse. When analyzing rapid reactivity events, methodologies are currently used with the aim of preventing cladding damage. These methodologies are robust and conservative, which is preferable, as this provides large safety margins against radiological releases. However, it is of interest to determine the magnitude of the safety margins, and this thesis work aims to quantify this if possible. This is done by developing a simplified chain from regulatory release limits and isotope inventory to the number of allowable cladding failures, with further work to determine the maximum enthalpy distribution in the core under typical maximum scenarios and a resulting enthalpy limit for falling control rod. You will work with, among other things, transient modeling using 3D code. The purpose is to investigate the impact of the conservatisms applied in the common methodology when analyzing the falling control rod event. This assignment is for 1 student. Requirements Specification We are looking for a student who is about to complete their academic studies and who wants to put their knowledge into practice through a thesis at Vattenfall. You are also someone who identifies with our principles: Active, Open, Positive, and Safety. We see that you are a self-directed and thorough person with strong analytical skills who has a genuine interest in technical modeling and is curious about nuclear power safety. You have experience working with complex data sets and simulations and also possess the ability to effectively document and present your technical results. Above all, you are interested in contributing to Vattenfall's goal of fossil-free and safe nuclear power. Education - You are studying technical physics, energy systems, or another relevant technical field, with basic knowledge in thermodynamics, fluid mechanics, and neutron physics. Language requirements: Swedish and English Scope – 30 hp Additional Information The assignment starts 2027-01-15 or by agreement Work location: Uppsala or Solna Application: attach a file containing your CV and a copy of your grades. Please note that you can only attach one file in the application, so it is important that the information is compiled in a single file. Application deadline: 2026-10-18 Contact person and supervisor at Vattenfall is Evelina Persäter, [email protected], 0732708110 Diversity and Inclusion – in everything we do At Vattenfall, we value being active, positive, open, and safety-conscious. We seek employees who share our vision and can help strengthen our corporate culture. We are convinced that diversity contributes to building a more profitable and attractive company and strive to be good role models regarding diversity. Vattenfall actively works to ensure that all employees have the same opportunities and rights regardless of age, ethnic or cultural background, gender identity, religion/belief, sexual orientation, or functional variation. Read more about how we work with diversity and inclusion here. Vattenfall is part of Sweden's critical infrastructure and our operations are governed by, among other things, rules on security protection, nuclear non-proliferation, and export control. Because of these rules, candidate screening is conducted for many of the positions in our operations before employment. For positions that lead to participation in security-sensitive activities or placement in a security class, this screening means that security clearance is conducted in accordance with the security protection legislation.