Session: 06-04-01 Marine Engineering and Technology I

Paper Number: 123423

123423 - Design Considerations for Fuel Cell Systems Employed in Long-Endurance Autonomous Small-Sized Subsea Robots 

Autonomous subsea robots are underwater robots that are programmable to operate independently subsea in seawater without a human operator. Autonomous underwater vehicles (AUVs) are a class of autonomous subsea robot vehicles that have been successfully developed and used for underwater surveys in search and exploitation of the vast seabed. Autonomous robots have the potential to significantly decrease operational costs associated with human operations and increase safety through the reduction of human errors. With the advancement in robotics today, many more are considering the use of autonomous subsea robots in a variety of industries, such as fish farming, subsea oil and gas, ocean renewables and even subsea mineral mining. The ability to have long endurance, i.e., to operate for long periods of time without refuelling, is crucial to reap the benefits of robot autonomy better. Fuel cells, with their significantly higher energy density compared to lithium batteries, offer an attractive option to provide the long endurance required. Fuel cells have been successfully used in various land-based applications, such as in cars and trains. However, to date, fuel cells have not been very much employed in underwater vehicles. Several subsea-related challenges arise when fuel cells are employed in subsea robots, which must be addressed. These include (i) underwater storage of hydrogen and oxygen, (ii) subsea-ambient environmental issues such as large hydrostatic pressures and cold ambient underwater conditions, (iii) dynamic manoeuvring actions by the robot that can cause large trim motions and (iv) fuel cell operations in a sealed container and with pure oxygen. This paper will discuss the most important design conditions that can arise when employing fuel cell systems for autonomous small-sized subsea robots with long endurance requirements.

Presenting Author: Yihan Xing University of Stavanger

Presenting Author Biography: Yihan Xing is a Professor of Mechanical Engineering and Subsea Technology at the University of Stavanger, Norway. He is a permanent faculty staff of the marine and offshore group at the Department of Mechanical and Structural Engineering and Material Sciences (IMBM) and the study program leader for M.Sc in Marine and Offshore Technology. Professor Xing teaches courses in subsea engineering, offshore field development and engineering mathematics. Professor Xing’s research interests are modelling and analysing large complex machinery systems, including using AI-enabled and stochastic design methods, particularly within large subsea cargo drones and offshore wind turbines, where he is most active. In addition, he also works in other areas, such as subsea and agricultural robotics and wave energy converters. Xing has authored more than 100 technical publications and reports. He has served and is serving on the editorial boards of more than 10 international journals. Further, he has seven years of experience in the subsea industry in pipeline engineering and product development. Xing is a Singaporean and has been living in Norway since 2008.

Authors:

žEljko Penga University of Split
Yihan Xing University of Stavanger
Merit Bodner Graz University of Technology
Tor-Olav Berntzen Hageroboten Jeeves AS