Design for safety and energy efficiency of the electrical onboard energy systems

Abstract

Treating the ship as an autonomous floating vehicle, onboard energy systems have to be designed to ensure high reliability for the safety of the ship per se and, also, of the passengers and crew under all operating conditions and emergencies at minimum cost. To date, these objectives have been achieved by strict safety regulations, design simplicity and component redundancies in safety-critical systems at the design stage. However, designing the systems with the current measures, the cost-ineffectiveness of the former approach would suffer. In addition, lack of strict regulations concerning environmental impact and also the relatively low vessel operation costs, lead to energy savings not being considered as driving force in the shipping industry. The recently introduced IMO regulations came into force to address the above objectives, imposing specific requirements during ship design and operation. This paper introduces a novel methodology for improving onboard systems availability and energy efficiency by logical and numerical modelling of the shipboard electrical energy systems during design and operation through the combined assessment of electrical power systems availability and quantitative performance. These, i.e. availability and performance, linked to initial and operating costs allow for multi-objective design optimisation of the electrical power systems

Dynamic Blackout Probability Monitoring System for Cruise Ship Power Plants

“…The investigated cruise ship diesel-electric power plant (DEP) includes 6 DGs, 3 azipods, 2 Power Management Systems (PMS) and 3 switchboards and multitude of other components as shown in Figure 2. Design data for this system was retrieved from the operating and maintenance manuals of the system components, the associated system drawings and studies published in the pertinent literature [42][43][44][45][46][47][48].…”

Cruise ships power plant optimisation and comparative analysis

“…Santoso et al [33] also compared the reliability of various diesel-electric propulsion systems in terms of their ability to respond to the system demands, reporting small differences in the reliability of the investigated alternative topologies. In [34], the cruise ship power plant safety was assessed in terms of post damage system availability and recommendations for the engine room locations were provided. In [35], the frequency of blackout was selected as a metric representing the system safety (instead of the reliability or availability employed in previous studies) and the Combinatorial Approach for Safety Assessment (CASA) was developed for calculating the investigated cruise ship power plant frequency of blackout.…”

“…• Each generator set can be loaded till operating at 90% of its nominal power. Above this load level [34], an additional available generator set will start and be connected to the ship electric network for covering the power demand.…”