**6. Conclusions**

Notably, the sulphur limit for automotive diesel is much lower than that for ship fuel. Across Europe, it is at 0,001%, 100 to 500 times below the 2020 limit for shipping. Therefore, it is most likely that the shipping industry will still be under scrutiny regarding the sulphur limits in marine fuels. The International Maritime Organization (IMO) has already taken steps to limit the sulphur content of ship fuels to 0.5% worldwide from 1st January 2020. The IMO has recently adopted an ambitious target to reduce GHG emission by 50% or from 940 mton (in 2008) to 470 mton (in 2050). This will serve as a driving force in introducing a broader range of environmentally friendly fuels, propulsion solutions and energy efficiency measures. This study has reviewed selected alternative ship fuels such as LNG, methanol and compared these fuels against heavy fuels oil with scrubbers in **Table 1** in terms of risks, price, infrastructure, regulations, availability of fuels, their environmental impacts, technologies required, capital expenditure (CAPEX), Operational expenditure (OPEX).

According to available research and information, LNG is the cleanest of fossil fuels which can satisfy the demand of shipping industry for years to come. However, it is not totally carbon free. For example, the release of unburned methane (so-called methane slip) could reduce the benefit of LNG over HFO. The prices of LNG on the market are comparable to the process of HFO. The price of methanol production also depends on which type of resource (e.g. natural gas, coal, biomass) is used as a feedstock. However, the prices of methanol are higher when compared to LNG and HFO. Although this methanol is gaining interest in the market because of its sulphur free and it, therefore, has the potential to meet the current 0.1% SOx emission in the Control Area requirements. Safety requirements for methanol as low flash point fuel must be followed according to existing rules, eg. IGF Code, which is still being expanded and developed by the IMO.

Being critical can also mean looking for reasons why we should not just accept big risk prediction as being binominal. By generating a prediction model which is fed by all aspects that leads to unwanted results such as fuel leakage, grounding, fire etc. a pre-notification system can be developed as in **Figure 9**. To establishing the similar model to the bunkering operations of alternative fuel oils, **Table 6** was generated. When we investigate the result of intended model what we are going to predict is binominal which means this model predicts the existence of leakage by answering "yes or no". However, it is highly possible that the methodology of the model can be extended toward answers which give possibility. By adding the possibility to the answers, the results are going to be more meaningful.

The wellness of the crew onboard is also another critical issue. Today's shipping industry is on the way to autonomous, and most of the inventions brought

**Figure 9.** *Comparison with Decision Tree Naive Bayes and SVM Learner.*

simplicity to onboard. By the time this easiness coming, most of the ship operators take advantages by reductions of the numbers of the crew onboard. While technological development has led to higher efficiency in maritime industry, some tasks, e.g. maintenance of the equipment or machinery, have not been affected by technical development and must still be handled manually in an often time-consuming manner [18]. Due to reduced staffing, these tasks must now be carried out by fewer employees. Lundh and her colleagues found that many engine room engineers reported using unauthorised shortcuts to be able to handle these tasks under time pressure [19]. These unauthorised shortcuts increase risks onboard the vessels. Briefly, the wellness of the crew must also be reflected in **Table 6** and algorithms.

Moreover, the ergonomy of the engine room is also essential for the shipping. For example, the study carried out by Lundh and her colleagues showed that the design of the engine control room and engine room is crucial for how different tasks are performed. According to this study, the design which does not support operational procedures, can induce an increased risk of exposure to hazardous substances and the engine crew members becoming injured [18].
