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Wind‐diesel sets offered as a reliable hybrid isolated power systems with reduction of fuel consumption, consists of variable speed wind turbines and fixed speed diesel engines. Load and wind energy variations cause, that the load power of the diesel genset is varied in wide range. Fixed speed generation set operates with the best efficiency only in a narrow range of the load, therefore implementation of a load adaptive, adjustable speed genset may additionally reduce fuel consumption.

Analysis of the system components model, simulation and laboratory tests on a small‐scale model.

Topology and output voltage control method of four‐wire adjustable speed autonomous wind‐diesel system dedicated for isolated power plants with high wind penetration.

The paper presents only part of the work which has to be done for the complete system. Load and energy management has to be applied in standalone system, as not in each operating point of proposed wind‐diesel system, can rated load be supplied. To fully prove the proposed system and control concept, tests of megawatt range system are advisable. To evaluate the fuel saving, a real wind and load profile in a selected isolated place is needed.

Every adjustable speed generation systems can save fuel. However, proposed topology in main part consists of known and implemented solutions, therefore costs of the new installation will not be increased significantly.

Proposed costs effective topology of adjustable speed wind‐diesel generation system has not been presented by any other authors. Standalone operation of doubly fed induction generator system is rarely reported in the papers.

Homogeneous charge compression ignition (HCCI) engine is an advanced combustion method to use alternate fuel with higher fuel economy and, reduce NOX and soot emissions. This paper aims to investigate the influence of ethanol fraction (ethanol plus gasoline) on dual fuel HCCI engine performance.

In this study, the existing CI engine is modified into dual fuel HCCI engine by attaching the carburetor to the inlet manifold for the supply of ethanol blend (E40/E60/E80/E100). The mixture of ethanol blend and the air is ignited by diesel through a fuel injector into the combustion chamber at the end of the compression stroke. The experiments are conducted for high load conditions on the engine i.e. 2.8 kW and 3.5 kW maximum output power for 1,500 constant rpm.

It is noticed from the experimental results that, with an increase of ethanol in the blends, ignition delay (ID) increases and the start of combustion is retarded. It is noticed that E100 shows the highest ID and low in-cylinder pressure; however, E40 shows the lowest ID compared to higher fractions of ethanol blends. An increase in ethanol proportion reduces NOX and smoke opacity but, HC and CO emissions increase compared to pure diesel mode engine. E100 plus diesel dual-fuel HCCI engine shows the highest brake thermal efficiency compared to remaining ethanol blends and baseline diesel engine.

This experimental study concluded that E100 plus diesel and E80 plus diesel gave optimum dual fuel HCCI engine performance for 2.8 kW and 3.5 kW rated power, respectively.

This study aims to improve the performance and to regulate the harmful emission from the diesel engine. For this purpose, palm oil biodiesel (POBD), waste cooking biodiesel (WCBD) and animal fat biodiesel (AFBD) are used for examination.

The transesterification process was followed to convert the three raw oils into biodiesels and the experiments are conducted at various loads with fixed 25 rps. Diesel as a reference fuel and three neat biodiesels are tested for emissions and performance. By training the experimental results in an artificial neural network (ANN), the best biodiesel was predicted.

The biodiesels are tested for significant fuel properties with the American Society for testing and materials standards and observed that kinematic viscosity, density and cetane number are recorded higher than diesel fuel. The fatty acid composition (FAC) from chromatography reveals the presence of unsaturated FAC is more in POBD (70.89%) followed by WCBD (57.67%) and AFBD (43.13%). The combustion pressures measured at every degree of crank angle reveal that WCBD and AFBD exhibited on far with diesel fuel. Compared to diesel fuel WCBD and AFBD achieved maximum brake thermal efficiency of 31.99% and 30.93% at 75% load. However, there is a penalty in fuel consumption and NOx emissions from biodiesels. On the other hand, low carbon monoxide, unburnt hydrocarbon emissions and exhaust smoke are reported for biodiesels. Finally, WCBD was chosen as the best choice based on ANN modeling prediction results.

There is no evident literature on these three neat biodiesel applications with the mapping of ANN modeling.

Purpose of this research is to shed light on the changes caused by shipping sulphur regulation, which will globally take off during years 2015 and 2020. It has significant effects on diesel markets globally, but especially in regions, where demanding 0.1 per cent level is required. One of these regions is the Baltic Sea. It is relatively undealt issue, how this forthcoming change will affect these specific sub-regions of stiff 0.1 per cent sulphur level demand and their transportation modes with different tax obligations.

The authors use second-hand data from various different sources, earlier research as well as simulation to estimate the effects on the diesel markets and transportation prices in the Baltic Sea region. Different transportation modes have diverging taxation treatment on diesel oil use, which complicates analysis further.

Based on research findings, it is rather probable that diesel markets for sulphur-free diesel oil shall face price spike in the beginning of 2015 in the Baltic Sea region. This is mostly explained with needed large-scale scrubber investment and short-time span to complete these (there are both technical and financial challenges). Therefore, numerous ships shall enter sulphur-free diesel oil market. Based on the simulation study, freight transportation will mostly be hurt in shipping, whereas road and rail shall face smaller price increases. Results are mostly explained with taxation treatment, where shipping is still using tax-free diesel oil, and no fixed taxes are hedging this transportation mode from sudden price changes.

Analysis concerns only Baltic Sea region, and effects and changes in the entire Europe from sulphur regulation change in 2015 are unknown. This would mean to extent study to North Sea. In addition, taxation system harmonization is not yet complete in Europe, and differences exist between member states. Research work was completed with diesel oil tax treatment regarding different transportation modes in Finland.

Based on this study, short sea shipping will be hurt by regulation change in 2015. However, in the future, this transportation mode shall face additional cost increases, as most probably, tax harmonization in diesel markets shall lead to fixed taxes added on shipping diesel. So, transportation mode shall face difficult and challenging times ahead.

Research is seminal study from possible sulphur regulation change implications in transportation mode level. It takes into account taxation treatment, cost share of diesel in transportation mode level and possible diesel price change. Until today, no other study exists in this detailed level.

This paper aims to compare the performance, emission and combustion characteristics of E20 biodiesel with diesel-water emulsion and eucalyptus water emulsion.

This research expounds the trans-esterification process apparently. Various biodiesel blends were made to go through the trans-esterification process to make it suitable for feeding them into the low heat rejection (LHR) engine. E20 biodiesel – 20% of eucalyptus oil by volume with diesel was chosen to carry out the research as it was found to be the best blend with diesel. The volume of water content in diesel water emulsions was varied by 5, 10 and 15% in DWM1 (Diesel Water Mixture1), DWM2 (Diesel Water Mixture2) and DWM3 (Diesel Water Mixture3), respectively. Similarly, the volume of water content in eucalyptus water emulsions was varied with emulsification ratio of E20 biodiesel. Partially stabilized zirconia was coated over top surface of the piston and valve facing of the LHR engine.

From the researches carried out, DWM3 (Diesel Water Mixture3) was found to be superior when compared with other diesel-water emulsions in LHR engine. The overall efficiency was found to be higher for EWM3 than other biofuels tested the in LHR engine.

This investigational experiment can be further extended to multi-cylinder engine and to improve the cetane number, Di ethyl ester (DEE) fuel additives can be added.

Transport of people and goods has always been associated with the generation of some form of pollution, whether atmospheric, sound or visual. Managing the urban environment presents a major challenge: preserving environmental resources and also ensuring decent living conditions for the current population and for future generations. In the era of motorized and carbonized transport, vehicles are the main source of emission of atmospheric pollutants, mainly in large urban centers and important precursors of ozone. An important advance in minimizing vehicle emissions was the introduction of cleaner and additive fuels into the Brazilian market. The purpose of this paper is to study the effect of the Dienitro additive on the NO_x and CO emissions in buses of collective transport, Diesel S-50 exhaust gas recirculation (EGR) and S-10 with selective catalytic reduction (SCR) and EGR systems. Measurements of CO and NO_x gas emissions were carried out using a gas analyzer in S50 and S10 diesel buses with an EGR and SCR systems from a company operating in the collective transport of Biguaçu.

In this study, 20 measurements were performed without additives and 20 measurements with additivation in each bus, making it possible to calculate the average emission rate of CO and NO_x, pollutant gases with toxic effect.

The usage of Dienitro additive in diesel engines resulted in a significant reduction in the emission of polluting gases, carbon monoxide (CO) and nitrogen oxide (NO_x), thus being efficient in reducing the emissions of these gases.

The Dienitro additive was first tested on diesel engines by public transport buses, and there is great potential for reducing the emission of toxic gases.

In the cylinders of a marine diesel engine, self-ignition occurs in a very short time after the fuel injection into the combustion chamber. Therefore, this paper aims to develop a model of diesel fuel spray for the early stage of fuel spray in the marine diesel engine. The main technical aspects such as nozzle diameter of the marine engine injector and backpressure in the combustion chamber were taken into consideration.

In this paper, laboratory experimental studies were carried out to determine parameters of fuel spray in an early stage of injection in the marine diesel engine. The optical measuring Mie scattering technique was used to record the fuel injection process. The working space was a constant volume chamber. The backpressure parameters in the constant volume chamber were the same as during the operation of the marine diesel engine. Based on the experimental studies and important Hiroyasu and Arai models of fuel spray presented in literature was proposed new model of fuel spray parameters for marine diesel injectors.

In this paper, the proposed new model of the two main parameters described fuel spray evolution”: new model of spray tip penetration (STP) and spray cone angle (SCA). New model propagation of fuel STP in time was included the influence of nozzle diameter and backpressure. The proposed model has a lower error, about 15%–34%, than the model of Hiroyasu and Arai. Moreover, a new model of the evolution over time of the SCA is developed.

In the future research of fuel spray process must be taken influence of the fuel temperature. Diesel fuel has a different density and viscosity in dependence of fuel temperature. Therefore are predicted of the expansion about influence of fuel temperature, new model of fuel spray for a marine diesel engine. The main limitations occurring in the research are not possible to carry out the research while real operation marine diesel engine.

An experimental test was carried out for a real fuel injector of a marine diesel engine. Design parameters and fuel injection parameters were selected on the basis of the actual one. In the literature, SCA is defined as a constant parameter for the specific preliminary data. A new model for the early stage of fuel spray of SCA propagation in time has been proposed. The early stage of fuel spray is especially important, because in this time comes in there to fuel self-ignition.

This paper aims to propose a comprehensive methodology for setting up rural electrifications for indigenous villages with minimum budgets and the lowest possible cost of electricity (COE). The electricity accessibility of rural area in Malaysia is not fully covered and the cost of extending the grid to these areas can be high as RM 2.7m per km. Lack of vigorous policies and economic attraction of the rural areas are also the main barriers to rural electrification. Electricity is an essential element of economic activities and the lack of electricity exacerbates poverty and contributes to its perpetuation. Therefore, a hybrid standalone power system can be an alternative solution for the rural electrification. A hybrid standalone power system is studied to investigate the potential of the implementation and the budget required.

A site survey has been carried out in a village in Peninsular Malaysia, namely, Kampung Ulu Lawin Selatan. A standalone hybrid system is modeled in HOMER Pro software and the data collected from the selected site are used to obtain the system configuration with the lowest COE. The load following and cycle charging energy dispatch methods are compared to identify the optimal system configuration that yields the lowest COE. The diesel generator-only system is chosen as a benchmark for comparisons.

The results show that the hybrid system constituted from the diesel generator, photovoltaic (PV), micro-hydro and energy storage using the load following energy dispatch method yields the lowest COE of RM 0.519 per kWh. The COE of the hybrid system is 378 per cent lower than that of the diesel generator-only system. The lead-acid energy storage system (ESS) is able to reduce 40 per cent of COE as compared to the system without ESS.

The results indicate that the COE of the diesel-micro hydro-PV-ESS system with load following dispatch strategy is RM 0.519 per kWh, and this value is 35 per cent higher than the average electricity price in Malaysia. However, it is important to note that the costs of extending the grid to the rural area are not taken into account. If this cost is considered into the electricity price, then the standalone hybrid power system proposed by this study is still a competitive alternative for rural electrification.

The demand for oil in agricultural production increases continuously with the world oil price soaring, reflecting a rigid growth characteristic, but there are no clear reasons for this. The purpose of this paper is to assess the essential reasons of this issue in theoretical and empirical perspectives.

The paper develops the model of derived demand for petroleum in agro‐production; analyzes the effect on agricultural labor‐machinery due to the changes in relative price of input factors; and reveals the reasons for the rigid growth of the demand for farm diesel; as well as estimates the substitution of agricultural machine for labor.

The results indicate that the rigid growth characteristic of the demand for farm diesel is due to the adjustment of the product and factor markets; and the most important reason is the changes in structure of the agro‐production inputs caused by the relative soaring price of agricultural labor‐machinery.

The government should attach importance to its impact on farmers and take effective measures to insure the stable development of agricultural production.

This research investigates the main reasons for the rigid growth characteristic of demand for oil in China's agro‐production from a novelty perspective. The proposed conceptual model is unique, it analyzes the substitution of agricultural mechanical for labor from the perspective of changes in relative price, and selects the two level constant elasticity substitution production functions to estimate the substitution of agricultural machinery for labor.

The purpose of this paper was to investigate the lubricity of palm biodiesel (PB)–diesel fuel with plastic pyrolysis oil (PPO) and waste cooking biodiesel (WCB).

Three quaternary fuels were prepared by mechanical stirring. B10 (10% PB in diesel) fuel was blended with 5%, 10% and 15% of both PPO and WCB. The results were compared to B30 (30% PB in diesel) and B10. The lubricity of fuel samples was determined using high-frequency reciprocating rig in accordance with ASTM D6079. The tribological behavior of all fuels was assessed by using scanning electron microscopy on worn steel plates to determine wear scar diameter (WSD) and surface morphology. The reported WSD is the average of the major and minor axis of the wear scar.

The addition of PPO and WCB to B10 had improved its lubricity while lowering wear and friction coefficients. Among the quaternary fuels, B40 showed the greatest reduction in coefficient of friction and WSD, with 7.63% and 44.5%, respectively, when compared to B10. When compared to B30a, the quaternary fuel mixes (B40, B30b and B20) exhibited significant reduction in WSD by 49.66%, 42.84% and 40.24%, respectively. Among the quaternary fuels, B40 exhibited the best overall lubricating performance, which was supported by surface morphology analysis. The evaluation of B40 indicated a reduced adhesive wear and tribo-oxidation, as well as a smoother metal surface, as compared to B20 and B30b.

Incorporation of PPO and WCB in PB–diesel blend as a quaternary fuel blend in diesel engines has not been reported. Only a few researchers looked into the impact of PPO and WCB on the lubricity of the fuel.