This study evaluates the issues of unintended excess pressure generation inside a cryogenic storage tank aboard a Norwegian-flagged vessel following its retrofitting with an LNG-diesel hybrid propulsion system. The research focuses on three central elements: quantifying the release of greenhouse gases, identifying the root causes of the pressure build-up, and evaluating potential solutions to mitigate the environmental impact. 

The findings present a comparative analysis of alternative solutions, ranked according to three criteria: environmental impact, energy retention, and economic feasibility. These solutions are critically discussed, culminating in a recommendation for the most suitable option based on the established criteria.