Diesel System Research Articles

Photovoltaic systems for Malaysian islands: Effects of interest rates, diesel prices and load sizes

Standalone diesel systems have been widely used on Malaysian islands due to the isolated locations of the islands. Nevertheless, the high diesel prices and the high cost of transporting diesel to islands cause the use of standalone diesel systems to be uneconomical. This study analyzes the feasibility of implementing PV (photovoltaic) systems as alternatives to standalone diesel systems by considering the effects of annual real interest rates, diesel prices and load sizes, using the HOMER (hybrid optimization of multiple energy resources) software. The results indicate that, at the ordinary diesel price of $ 0.61/L, low interest rates (0–3%) are desirable for the implementation of hybrid PV/diesel with battery systems over standalone diesel systems, regardless of the load sizes. Although different load sizes may affect the decisions on the implementation of PV systems at higher interest rates (6–9%), these effects become less pronounced as the price of diesel increases to $ 1.22/L or higher. Also, under high diesel prices, the choice of optimal system configurations obtained for small load sizes should be applicable for larger load sizes, albeit with different component ratings. Although the current study is intended for Malaysian islands, the findings can be generalized for other places with similar solar radiation levels.

Evaluation of the Levelized Cost of Energy Method for Analyzing Renewable Energy Systems: A Case Study of System Equivalency Crossover Points Under Varying Analysis Assumptions

A modified levelized cost of energy (LCOE) model was created to determine the economic crossover point (measured in ${{\hskip1pt}{\ssr C} {\hskip-7pt} \raise2.4pt \hbox{$\buildrel{\vrule depth0.5pt width5.5pt} \over{\vrule depth0.5pt width5pt}$}{\hskip2pt}}/\hbox{barrel} $ of oil) between a traditional diesel power-generating facility and a hybrid closed-loop wind–hydro energy system on the island of El Hierro. This island represents the first system-of-systems coupled wind and pumped-storage hydroelectric facility in the world aimed at achieving energy independence for an island. LCOE models were developed using fixed baseline oil prices of 30, 40, and 50 ${{\hskip1pt}{\ssr C} {\hskip-7pt} \raise2.4pt \hbox{$\buildrel{\vrule depth0.5pt width5.5pt} \over{\vrule depth0.5pt width5pt}$}{\hskip2pt}}/\hbox{barrel} $ , which is the price range when the construction project was undertaken. The percentage change of the Spanish consumer price index and industrial price index were used to assess the effect of changing oil prices on the LCOE. This paper involved on-site investigation of the technical and financial elements of the project and resulted in an LCOE model that includes investment, operation and maintenance, emissions, and land costs. Sensitivity analyses were carried out at varying inflation and discount rates. Results indicate that the economic crossover point between the energy production systems to be below the current world oil price and within the range of prices when the project was initiated. Increasing inflation rates reduces the crossover point by increasing future costs associated with the diesel system, and increasing discount rates raises the crossover point by discounting future costs associated with diesel fuel expense. Under constant dollar analysis, the LCEO model robustly highlights system equivalency points; however, the inclusion of discount rate challenges this robustness by introducing the potential for gaming the analysis in favor of one technology over another.

Analytical Comparison of Static and Dynamic Reactive Power Compensation in Isolated Wind–Diesel System Using Dynamic Load Interaction Model

This article presents static and dynamic reactive power compensators together for a self-excited induction generator and synchronous generator based isolated hybrid power system. Reactive power is required for excitation of the induction machine and for load under steady-state and transient state operations in an isolated hybrid power system. For small perturbation of load reactive power and input wind power, the use of a dynamic compensator alone may give better voltage stability but at a high cost; in contrast, the static compensator reduces the cost on compromising with the voltage stability. The proper rating selection of both compensators used may give the optimum solution between the voltage stability as system performance and cost of compensation. The fixed costs and voltage profiles are compared for the different participations of the fixed capacitor bank and STATCOM. The interaction of the dynamic load model is also introduced to make the system more reliable and hence a new power balance equation is derived. A 10% step disturbance in the dynamic load model as well as wind power input is considered for the system study. Four different cases designed for unique participation of static and dynamic reactive power compensators are presented. The analytical comparison is based on cost, rating selection, and voltage stability under transient condition.

Chemico-physical features of soot emitted from a dual-fuel ethanol–diesel system

The paper describes an experimental study aimed to characterize the impact of the dual-fuel ethanol–diesel combustion system on size, number and chemical characteristics of the emitted carbonaceous particles. The tests were conducted on a single cylinder research engine provided with a modern architecture and properly modified in a dual-fuel (DF) configuration. In particular, the experimental campaign was aimed to evaluate in detail the effect of the use of the ethanol as port injected fuel in diesel engine on the size distribution function, morphology, reactivity and chemical features of the exhaust emitted soot particles. The engine tests were chosen properly in order to represent actual working conditions of an automotive light-duty diesel engine. The morphological and chemical features of soot particles were studied in dependence of the ethanol–diesel substitution rate by analyzing the soot collected at the engine exhaust. Results indicated a significant effect of ethanol fumigation on the concentration of the emitted particles but not on the average size, as well as, a negligible impact of ethanol premixed charge on the soot nanostructural features.

Economic analysis of PV/diesel hybrid system with flywheel energy storage

This paper analyzes a hybrid energy system performance with photovoltaic (PV) and diesel systems as the energy sources. The hybrid energy system is equipped with flywheel to store excess energy from the PV. HOMER software was employed to study the economic and environmental benefits of the system with flywheels energy storage for Makkah, Saudi Arabia. The analysis focused on the impact of utilizing flywheel on power generation, energy cost, and net present cost for certain configurations of hybrid system. Analyses on fuel consumption and carbon emission reductions for the system configurations were also presented in this paper.

Optimal combination of solar, wind, micro-hydro and diesel systems based on actual seasonal load profiles for a resort island in the South China Sea

This paper proposes multiple optimal combinations of hybrid renewable energy systems for a resort island based on actual generation-side energy auditing, assessment of seasonal renewable energy resources availability versus load profiles, and techno-economic analyses. The resort island selected is Tioman, as it represents the typical energy requirements of many resort islands in the South China Sea. The island relies mainly on diesel fuel for electricity generation. However, diesel is subjected to high and volatile market prices, high operation and maintenance costs, and poses environmental risks. Therefore, to mitigate diesel fuel dependency, an optimal combination of hybrid renewable energy systems is proposed. The project starts with an actual generation-side auditing including the distribution of loads, seasonal load profiles, and types of loads as well as an analysis of local development planning. Subsequently, surveys of available renewable resource potentials such as solar, wind, and hydro were conducted that involved collection and analysis of meteorological data. Furthermore, reconnaissance study for hydro potentials has been based on topographic maps and hydrological studies. Finally, HOMER (Hybrid Optimization Model for Electric Renewable) software was used to perform techno-economic analyses for the hybrid system. Results of the analyses include the optimal system configurations, cost of hybrid system, fuel saving, and CO2 emission reduction.

Technoeconomical Assessment of Optimum Design for Photovoltaic Water Pumping System for Rural Area in Oman

Photovoltaic (PV) systems have been used globally for a long time to supply electricity for water pumping system for irrigation. System cost drops down with time since PV technology, efficiency, and design methodology have been improved and cost of wattage drops dramatically in the last decade. In the present paper optimum PV system design for water pumping system has been proposed for Oman. Intuitive and numerical methods were used to design the system. HOMER software as a numerical method was used to design the system to come up with optimum design for Oman. Also, REPS.OM software has been used to find the optimum design based on hourly meteorological data. The daily solar energy in Sohar was found to be 6.182 kWh/m2·day. However, it is found that the system annual yield factor is 2024.66 kWh/kWp. Furthermore, the capacity factor was found to be 23.05%, which is promising. The cost of energy and system capital cost has been compared with that of diesel generator and systems in literature. The comparison shows that the cost of energy is 0.180, 0.309, and 0.790 USD/kWh for PV-REPS.OM, PV-HOMER, and diesel systems, respectively, which sound that PV water pumping systems are promising in Oman.

Economic perspective of hybrid wind-diesel technology for commercial loads of Dhahran Saudi Arabia: A step towards sustainable future

The governments world-wide are deliberating to promote renewable energy sources such as wind to mitigate increasing demand of energy and to overcome effects of pollution due to to use of fossil fuels. Integration of wind turbine generators (WTG) with the diesel plants is pursued widely to reduce dependence on fossil-fuels and to reduce carbon emissions. Literature indicates that commercial/residential buildings in the Kingdom of Saudi Arabia (K.S.A) consume an estimated 10 - 40% of the total electric energy generated. The aim of this study is to analyze wind-speed data of Dhahran (East-Coast, K.S.A.) to assess the economic feasibility of utilizing hybrid wind-diesel power systems to meet the load requirements of a typical commercial building (with annual electrical energy demand of 620,000 kWh). The monthly average wind speeds range from 3.3 to 5.6 m/s. The hybrid systems simulated consist of different combinations of 100 kW commercial WTG supplemented with diesel generators. NREL?s (HOMER Energy?s) HOMER software has been employed to perform the techno-economic analysis. The simulation results indicate that for a hybrid system comprising of 100 kW wind capacity together with 175 kW diesel system, the wind penetration (at 37 m hub-height, with 0% annual capacity shortage) is 25%. The cost of generating energy (COE, $/kWh) from this hybrid wind-diesel system has been found to be 0.121 $/kWh (assuming diesel fuel price of 0.1$/liter). The study exhibits that for a given hybrid configuration, the number of operational hours of diesel gensets decreases with increase in wind farm capacity. Emphasis has also been placed on wind penetration, un-met load, energy production and COE, excess electricity generation, percentage fuel savings and reduction in carbon emissions (relative to diesel-only situation) of different hybrid systems, cost break-down of wind-diesel systems, COE of different hybrid systems, etc.

Heat loads on the waste heat recovery scavenge air cooling system of the maine marine diesel on the route line

Heat loads on the waste heat recovery scavenge air cooling system of the maine marine diesel on the route line

Optimisation and Improvement of Voltage stability in a Standalone Wind-diesel-micro Hydro Hybrid System

This paper suggests the application of PSO based SVC controller for Reactive Power compensation and optimisation of an isolated hybrid system consisting of wind diesel and micro hydro system. The small signal linear model of the hybrid wind Diesel micro hydro model is considered with different loading conditions. The reactive power compensation and stability analysis have been carried out with SVC Controller with an IEEE exciter I. The PSO algorithm is used to optimise the SVC controller and a comparison is made with the GA based controller. The system undergoes through variable wind power inputs and uncertain load change. The stability of the system is verified from the eigen value analysis.

Results of Vortex Tube Usage in Diesel Exhaust Gas Recirculation System

The article outlines the results of vortex tube usage in exhaust gas recirculation system of diesel 4ЧН13/15. It presents main functional features of a vortex tube. It is shown that the usage of the tube allows reducing the temperature of recirculated gas up to 60°C and significantly diminishes the content of nitrogen oxide and particulate matter in exhaust gases of an engine at general operation modes, conforming to the Rule of Economic Commission for Europe Organization of United Nations #96.

Neem Biodiesel - A Sustainability Study

Azadiractha Indica (Neem) is one of the promising tree species suitable for providing oil for biodiesel production. This paper addresses the life cycle assessment (LCA) with respect to, global warming potential, acidification potential and energy balance of a small scale biodiesel system using Neem oil as feedstock, in rural Karnataka (a southern state in India). The environmental impacts have been bench marked with the life cycle impacts of fossil diesel system and Jatropha. Global warming potential of Neem biodiesel life cycle (338 gCO2-eq Functional Unit -1* ) was found be 1.2 times higher than fossil diesel system (280 gCO2-eq Functional Unit -1 ) and 2.7 times higher than Jatropha biodiesel system(123.7 gCO2-eq Functional Unit-1). Acidification potential of Neem system was found to be negligible. It is observed that one hectare of Neem plantation is capable of sequestering the 1.35t of biogenic CO2 released during the Neem biodiesel life cycle, with additional sequestration potential of 8.65 t CO2 ha -1 . Net energy ratio of Neem biodiesel life cycle (22.06) has been found to be 26 times higher than fossil Diesel system and twelve times higher than Jatropha system (1.85). This life cycle study revealed that producing biodiesel from Neem oil is ecologically sustainable.

Sizing of off-grid renewable energy systems for drip irrigation in Mediterranean crops

In the Mediterranean region, there are many drip irrigation systems with pumps that are powered by diesel generator sets (gensets). Although they could be powered by renewable energy produced on-site, technical and economic factors make that difficult. Moreover, the seasonal nature of demand requires an oversizing of energy generation and/or storage, increasing system costs. In this paper, we sought renewable energy systems that were economically optimal. We focused on six farming facility case studies to find the optimal energy generation solution using a simulation and optimization tool based on genetic algorithms. Photovoltaic-diesel hybrids and diesel systems were found to be optimal, with energy costs from 0.13 to 1.08 €/kWh and from 0.32 to 0.52 €/kWh, respectively. The strong effect of demand management was an interesting finding, as it may indicate significant system size and cost reductions. In addition, the optimum photovoltaic fixed tilt angles depended not only on the seasonal profile of the demand, but also on the pumping schedule. Although the difference between market interest rates and the rise of fuel prices strongly influences the advantage of incorporating, or not, renewable generation, this study supports that hybrid photovoltaic-diesel systems can make profitable use of renewable energy in drip irrigation.

Development of Efficient Operational Mode for Wind-Diesel Hybrid System

Hybrid wind Diesel stand-along systems are considered economically viable and effective to create balance between production and load demand in remote areas where the wind speed is considerable for electric generation, and also, electric energy is not easily available from the grid. In Wind diesel hybrid system, the wind energy system is the main constitute and diesel system forms the back up. This type of hybrid power system saves fuel cost, improves power capacity to meet the increasing demand and maintains the continuity of supply in the system. Problem we face in this system is that even after producing enough power through wind turbine system, considerable portion of this power needs to be dumped due to short term oversupply of power and to maintain the frequency within close tolerances. As a result remaining portion of total energy supplied comes from the diesel generator to overcome the temporal energy shortage. This scenario decreases the overall efficiency of hybrid power system. In this study, efficient Simulink modeling for wind-diesel hybrid system is proposed and some simulations study is carried out to verify the feasibility of the proposed scheme.

Study on SO2-Absorption Behavior of Composite Materials for DeSOx Filter From Diesel Exhaust

NOx emitted from diesel engines is one of the major air pollutants in most countries. To reduce NOx emission, NOx storage/reduction (NSR) catalysts have been developed for diesel systems. The catalyst for NSR is strongly poisoned with sulfur. This paper reports the synthesis of Na-doped CaCO3 as a new material for SO2 adsorption. Measurements of the desulfurization breakthrough characteristics using monolith washcoated Na-doped CaCO3 were investigated at 450°C. The Na-doped CaCO3 absorbed ∼77.6–90.6 mg-SO2/g-material of SO2 at 450°C (where CaCO3 is 8 mg-SO2/g-material). Investigation of the source of the improved sulfur absorption capacity of the Na-doped CaCO3 relative to the parent material via x-ray diffraction (XRD) and scanning electron microscopy–energy-dispersive x-ray spectroscopy (SEM-EDX) analyses revealed that the new material forms a composite partially composed of Na2Ca(CO3)2. The enhanced SO2 absorption capacity derived from the formation of composite materials is demonstrated herein. SO2 contained in the exhaust gas is absorbed at a lower temperature than with previously reported systems. In order to elucidate the SO2 absorption mechanism of the composite materials, further studies and synthesis of materials with greater absorption capacity are required.

Organizational Practices Lean Enterprises Adopt to Focus on Value Streams

The purpose of this article is to investigate which practices lean enterprises adopt to focus on value streams. A case study of three plants: Delphi Diesel Systems, Sogefi Filtration, and a company within the furniture industry is presented. The three plants have successfully performed a lean transformation with significant performance improvements, respectively, to Delphi Diesel Systems, Sogefi Filtration, and a company within the furniture industry. The organizational practices under analysis are (1) the establishment of organizational units based on value streams, (2) the use of a performance measurement system based on value streams, and (3) the adoption of a formal meeting system. These organizational practices were found in all three of the studied plants and have been implemented in all of their organizational units; even concrete implementation detail differs between plants. This research provides a contribution in the fields of organizational practices and the transition to lean enterprise by est...

Real power and frequency control of a small isolated power system

This paper describes the dynamic analysis of a small isolated power system comprising a wind turbine generator and a diesel generator. The analysis is carried out in time domain considering simplified models of the system components by taking into account the wind turbine pitch controller and the diesel engine speed governor. Wind disturbance model consisting components of gusting of wind, rapid ramp changes and random noise. The wind generator is always operated with its rated power and the additional power required by the load is supplied by the diesel generator. For better dynamic performances of wind–diesel system under wind and load disturbance conditions, two control schemes are used. In the first case, a proportional–integral (P–I) controller and in the second case a proportional–integral–derivative (P–I–D) controller are used. Gain parameters of these controllers are optimized using genetic algorithm (GA) and Particle swarm optimization (PSO) considering two different objective functions and the results are compared. The sensitivity analysis of the wind diesel system is carried out for parameter uncertainties and the stability of the system is analyzed using D-stability criterion. Analysis is also carried out to examine the effect of power injection to a 69 bus radial distribution network by wind–diesel isolated system.

Biodiesel in Brazil: A Market Analysis and Its Economic Effects

The commercial production of biodiesel in Brazil began in 2005 and increased in such a way that the country has become one of the largest producers in terms of volume in 2012. This study aims to analyze the biodiesel market in Brazil and its socio-economic effects resulting from the mandatory addition of biodiesel in the distribution system of mineral diesel. This work is characterized as a qualitative and exploratory study. The technical procedures adopted include literature research and data collection from government agencies involved. It is highlighted that the Programa Nacional de Producao e Uso de Biodiesel no Brasil - PNPB (“National Program for Production and Use of Biodiesel in Brazil”) was designed for the purposes of: promoting rural development; the growth of biodiesel production plants; and positively impact the environment. The survey showed the following results: i) significant increase in investment in renewable energy, especially biodiesel, ii) a high unused capacity in the biodiesel production plants; iii) a high dependence on soy for biodiesel production, iv) unfavorable prices of oilseeds; v) high concentration of the biodiesel market; vi) difficulty in standardizing the biodiesel auctions; vii) a small increase in inflation; viii) increased generation of income, employment and Gross Domestic Product (GDP) due to the presence of biodiesel in the energy market. It was found that by adding a percentage of biodiesel to diesel oil caused positive impacts on the national economy, contributing to improvement in employment policies, income distribution, environmental issues, technological and regional development.

Building Integrated Hybrid PV-Battery-Diesel Generator Energy System for Oil Producing Communities in Niger-Delta Region of Nigeria

The potential of the use of hybrid PV-Battery-Diesel generator for household in the rural oil producing communities in the Niger Delta of Nigeria is presented. The analysis was done by the optimum configuration of the hybrid system through top-ranked system configuration, according to the Net Present Cost (NPC) in the HOMER platrform. The optimal system delivers the best components alongside appropriate operating strategies to provide the most efficient, reliable cost -effective system possible. The system investigate reduces CO2 emissions by 28.2%/year. The implementation of the hybrid RES will, therefore, reduce the emission level of the over-polluted Niger Delta region by the activities of oil producing companies and the use of standalone diesel generators. The system has a better potential for providing the energy needs of the households in the oil producing communities as compared to a standalone Diesel system as net present cost is reduced by 17%. However, reliabilty of power supply is assured with the hybrid RES

Stability analysis and reactive power compensation issue in a microgrid with a DFIG based WECS

This paper presents a novel methodology for compensating reactive power in a microgrid, having a DFIG based wind–diesel system, to enhance the voltage stability of the hybrid system. UPFC as a FACTS device is proposed in order to improve the control of reactive power mismatch and the stability of the system. A small signal model of the wind–diesel system, DFIG based wind turbine system, UPFC and the controllers are designed for the stability analysis. Further, the voltage variation and reactive power compensation is analysed with the incorporation of proposed ANFIS based UPFC controller. Simulations are performed in MATLAB environment for transient stability analysis in a wind–diesel based microgrid with different wind power input and 2% step increase in load demand. Simulation results illustrate the efficiency and effectiveness of the proposed approach and its impact upon transient behaviour of the microgrid.