Doctoral theses of the School of Engineering are available in the open access repository maintained by Aalto, Aaltodoc.
Public defence in Energy Engineering, MSc Mia Elg
Public defence from the Aalto University School of Engineering, Energy and Mechanical Engineering Department.
Title of the thesis: Modelling, analysing and optimising ship energy systems – For decarbonised shipping
Thesis defender: Mia Elg
Opponent: Prof. Esa Vakkilainen, LUT, Finland
Custos: Prof. Risto Lahdelma,Aalto University School of Engineering
Optimising ship design towards net-zero – energy systems at the heart of maritime transformation.
Shipping is undergoing a major transition. The focus in ship design has shifted toward environmental sustainability and energy efficiency, with ship energy systems at the core of this change. This doctoral thesis examines how energy system modelling, analysis, and optimisation can guide ship design toward a low-emission and commercially viable future.
Optimisation is a key tool in supporting design decisions. This thesis investigates optimisation in two contexts: supporting machinery selection and developing ship machinery through battery sizing and waste heat recovery tasks. Additionally, hydrogen integration is examined at the system level in a conceptual case study of a cruise ship operating on a Mediterranean route. Results show that energy savings can reach up to 25% when various technologies are combined into a hydrogen-powered machinery setup – compared to traditional design with conventional fuels.
The research highlights that energy efficiency is not achieved through isolated solutions, but also through system interactions. Heat utilisation analysis based on entropy generation offers new perspectives on waste heat recovery. Furthermore, integrating optimisation into design simulation tools saves time and improves result reliability.
This thesis provides methods and insights that support designers in the early stages of ship design – the phase where critical decisions about the ship’s energy system and future emissions are made. It demonstrates that energy efficiency optimisation is a multifaceted task requiring technical understanding, system-level thinking, and the ability to make pragmatic choices. As international regulations tighten, including the Carbon Intensity Indicator (CII) and FuelEU Maritime, this work provides timely insights into how ships can meet future standards while remaining commercially viable.
Keywords: Ship energy system, modelling, optimisation, analysis, energy saving, entropy generation
Thesis available for public display 7 days prior to the defence at .
Contact information:
E-mail: mia.elg@deltamarin.com
Phone: +358 50 3788 333
LinkedIn: www.linkedin.com/in/mia-elg
Doctoral theses of the School of Engineering
Zoom Quick Guide