In recent years, the usage potential of alternative energy sources has been gaining importance to increase the efficiency of ships within the scope of the obligations brought by international maritime regulations. The possibility of using alternative energy sources such as solar energy, wind energy, fuel cells, and waste heat recovery technologies on ships has been evaluated in the literature. Today, ships also have waste heat recovery systems as standard equipment for this purpose, and this method is suitable for thermoelectric generators that generate electricity from temperature differences on shipboards. This article aims to review the thermal technologies for the power generation of shipboards. By conducting a case study, an energy efficiency increase was obtained when functional areas were selected on a practical ship, and the effect of this efficiency increase on emissions was examined. As a result of the research, it was discovered that thermoelectric generators increased onboard energy efficiency and have significant potential for sustainability in the maritime sector.

Sea pollution has negative consequences and has an impact on the marine ecosystem and ship machinery processes. The main risk of sea pollution on ship is based on sea chests that are used for ballast water and firefighting. In addition to this, sea chest fouling, which primarily forms as a result of pollution, has an impact on the ship machinery, navigation in waterways, and the environment. The possibility of failure related to sea chest fouling issues in seawater cooling systems used to cool ship machinery parts were investigated in this study. Significant defects in the cooling and related engine systems were determined using both a full-mission Kongsberg engine room simulator (ERS) process and failure modes and effects (FMEA) technique, which relied on expert judgments within the cause–effect relationship. According to the findings, sea chest pollution has a direct impact on the ships’ cooling water systems and other related components, causes power losses, and leads the main engine to shut down, resulting in the ship losing maneuverability. As a result of these circumstances, the risk of catastrophic events such as grounding, contact, collision, flooding, fire explosion, and others was determined.

In recent years, ecological degradation has increased and drawn many environmental problems with it. One of the outcomes is the mucilage problem, which directly affects tourism, fishing, and especially the maritime sector. The recent mucilage outbreak in the Sea of Marmara has brought attention to these environmental disaster-related studies. However, there are only a few studies about mucilage’s effect on maritime transportation. In this context, the impact of mucilage on a marine vessel is examined within the scope of the study. One of the major negative effects of mucilage on a vessel is, its cooling system. Due to the mucosal formation of mucilage, it clogs the filters and reduces the cooling effect of seawater. In our paper, a case study was made, and data was obtained from a simulator. The seawater filter in front of the seawater pump was clogged by 0%, 30%, 45%, and 60% during the simulated case studies. 0% is the base condition that is not clogged by the mucilage while the other three cases are partially clogged. A comparison study was made according to the data gathered from the simulator. While the filter is clogged by 60% main engine is in slow down condition, but during 30% and 45% of cases, pumps tried to compensate cooling effect by increasing the seawater flow. However, enough cooling effects on the main engine jacket water, air cooler, lubrication oil cooler, steam condenser, and air compressor were not provided. Moreover, the reduced cooling effect increases fuel oil consumption which leads to higher CO2 emissions. These results show that mucilage not only affects fishing, and tourism but also affects the environment by increasing the fuel oil consumption of a vessel.