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Green technologies are considered to be one of the most significant way to mitigate the severe global warming effect and have been drawing attentions from researchers all over the world. Solar energy is a type of renewable energy and solar panel array can capture and convert solar energy to electricity for domestic and industry uses. This paper considers the application of solar panel array to propulsion system of a short route ferry operating in the Marmara Sea where currently no environment protection policy is active to guide marine activities. The evaluation of the application is carried out using life cycle assessment from the aspect of cost effective and environment friendly. To take the payback time of the system into account, this study investigate the difference due to different average daily sunny hours in the operating area considering three levels of carbon credits. The results indicates both average daily sunny hours and carbon credits have an impact on the payback time. With the highest average daily sunny hours and carbon credits, the payback time of the application is only 2 years.

This paper is to develop a coordinated control strategy of a ship with hybrid power and evaluate on the energy efficiency and emissions reduction of the case ship. The hybrid power system consists of 4-stoke diesel generator, solar panels and battery packs. A micro-grid power system was structured to offer an optimal combination of the three power sources in terms high efficiency and low emissions of the overall system. The control requirements for the developed micro-grid power system were analysed according to the principles of priority to use renewable energy. A power distribution control strategy was designed by applying the logic threshold method. A system simulation model was established and the simulation was carried out with MATLAB. An experimental test rig was built to evaluate the simulation results and develop the control system. The developed marine micro-grids power system has been applied on a case ship and run stably. Compared with the conventional power system, the performance of emission and economic of the hybrid system is studied with the case ships. The results of case ship and experimental have shown that the developed hybrid micro grid system can be managed effectively by the proposed control strategy. The emission of CO2 is dramatically decreased in any cases and the energy cost is reduced considering for the ship life-cycle.

Computational fluid dynamics (CFD) is used to investigate the performance of a large two-stroke marine diesel engine. The simulated model is validated with experimental data. The in-cylinder pressure of the simulated model is in agreement with the experimental data. The errors of NOx and CO2 emissions are also within the accepted range. The effect of Miller cycle, injection sequence and pilot injection on combustion and emissions are investigated using this model. The results show that the in-cylinder pressure decreases with deeper Miller cycle level. However, NOx emissions are reduced only slightly to 8.95 g/kWh. This decrease in NOx emissions does not satisfy the requirements of Tier III. We also found that the injection interval angle between two injectors decreases the combustion pressure. However, the indicated specific fuel consumption is 7.3 g/kWh higher than the base value, when the injection interval angle is 8 °CA. Appropriate pilot injection strategy can decrease NOx emissions and indicated specific fuel consumption, such as P10I5. However, NOx emissions are not reduced sufficiently to meet the requirements of Tier III.

Owing to high operation cost of traditional power systems and serious environmental situation, the usage of hybrid power system on board is increasingly attracting attentions. Applying life cycle assessment (LCA) approach, the key objective of this paper is to evaluate and optimise the operational modes of hybrid power system for a short-route ferry in Scotland. The applied hybrid system is mainly comprised of generators and lithium ion batteries and there are four operational modes based on the power requirements during voyages. To carry out this study, a top-bottom design strategy is applied to build up the short route ferry with hybrid power system in GaBi. The cradle to grave of the ferry is modelled referring to a practical ship life: con-struction, operation, maintenance and dismantling. In order to determine the optimal power distribution and minimal emissions, a series of operation profile cases with different power distributions were investigated for a certain route with following operational phases: transiting, manoeuvring and at slip. The comparison results from different voyage phases indicated the optimal power distribution between gen-sets and batteries with minimised operation costs. The environmental assessments for each case were carried out in order to identify the relationship between power distributions and emissions. The study concluded that there are sig-nificant impacts on the energy consumption and environment during the life cycle of a hybrid power system and therefore it is essential to apply appropriate operation optimisation on the system.

The effect of ammonia distribution upstream selective catalytic reduction converter on selective catalytic reduction conversion efficiency has been studied in this paper. The results indicate that the more uniform ammonia concentration distribution upstream converter is, the higher NOx reduction rate and lower NH3 slip can be achieved. By using static mixers fixed in the pipeline upstream converter, ammonia and exhaust streams can be mixed effectively on the limitation of mixing distance for marine selective catalytic reduction system. Different kinds of static mixers could lead to different degree of mixing between ammonia and exhaust streams, which will affect selective catalytic reduction conversion efficiency directly. Then comparing with the complete mixing degrees of ammonia and exhaust streams, selective catalytic reduction conversion efficiency can be used as an evaluation index for static mixers. Based on CFD method, the effect of mixing degrees of different static mixers on selective catalytic reduction conversion efficiency can be obtained by simulating current commercial catalysts with several different kinds of static mixers such as GK mixer, SK mixer, contour mixer, star-shaped mixer. The trend of NOx reduction rate and NHx slip changing with ammonia distribution and velocity distribution before selective catalytic reduction catalyst layers can be summarized by analyzing the simulating data. The results can be used to help engineering applications.

At present, the problem of environment pollution draws people's attention increasingly. The international communities and organizations established relevant laws to restrict the emission and reduce the harm to human being and environment. In this paper, a numerical simulation model for diesel engine was established by GT-POWER in order to study the NO, CO and HC emissions characteristic of the diesel engine and the model was validated by experimental data. Based on the model, the variable parameters including injection timing, intake air temperature, compression ratio and EGR ratio were carried out. The simulation results showed that with the decrease of CA BTDC, intake air temperature, compression ratio and EGR ratio respectively, the NO emission decreased. However, the CO and hydrocarbon emissions increased.

Fuel saving and low carbon emission in shipping have already become an attractive and important subject in the shipping industry driven by the increasing full oil price and considerations of reduction of green house gas emission. Global shipping consumes 200 million tons of liquid fuel, resoluble for 1.12 billion tons of CO2 emission in the world. This paper presents the development of a novel forward dynamic programming method to optimise ship’s fuel consumption with respect to safety during a voyage. The constraints are weather, sea conditions and the safety constrains defined in the IMO guidance MSC.1/Circ.1228. Compared with the traditional dynamic programming methods, the newly developed weather routing method is more accurate and practical. Simulation results from a case study have shown that the newly developed method is able to save several tons of fuel compared with that of the traditional methods for one North Atlantic voyage. As a result, it can offer much CO2 emission reduction.

Selective catalytic reduction with NH3 is considered one of the most effective technologies controlling NOx emission. Metal Fe-based catalysts were used in the investigation to improve low temperature performance of NOx conversion. The temperature range studied was betweet 15 degrees C and 350 degrees C in increments of 50 degrees C. The honeycomb catalysts were prepared by an impregnation method. The study also included characterisation of catalysts by BET, XRD, H2-TPR and XPS methods. It was found that an increase in metal Fe content from 2 to 6% wt offered an improvement in the catalytic performance. However, a further increase in Fe content resulted in a decrease in its performance. More than 90% NOx conversion rate could be achieved over the Fe-based honeycomb catalyst at a low temperature by doping with different weights of Ni and Zr metals. Amongst all the catalysts studied, the mixed metal catalyst of Fe-Ni-Zr was the one with most potential. This was because of its higher NOx conversion rate at a low temperature and also because of its wider operating temperature window. The effect of gas hourly space velocity (GHSV) was also investigated and the results showed that as GHSV increased, the reduction of NOx decreased.

Selective catalytic reduction with NH3 is considered as one of the most effective technologies controlling NOx emission. Metal Fe based catalysts were used in the investigation to improve the low temperature performance of NOx conversion. The temperature range studied was between 150 degrees C and 350 degrees C with the interval of 50 degrees C. The honeycomb catalysts were prepared by an impregnation method. The study also included characterization of catalysts by BET, XRD, H2-TPR, SEM and XPS methods. It is found an increase in metal Fe content from 2 to 6 % wt. offers an improvement in the catalytic performance. However, a further increment in Fe content will result in a decrease in its performance. More than 90 % NOx conversion rate could be achieved over the Fe-based honeycomb catalyst at a low temperature by doping with Ni and Zr metal with different weights. Among all the catalysts studied, the mixed metal catalyst of Fe-Ni-Zr is found the most potential one, not only because of its higher NOx conversion rate at a low temperature, but also because of its wider operation temperature window. The effect of gas hourly space velocity (GHSV) was also investigated in the study and results show as GHSV increases that reduction of NOx is decreased.