Backup Diesel Generator Research Articles

Virtual Generator to Replace Backup Diesel GenSets Using Backstepping Controlled NPC Multilevel Converter in Islanded Microgrids with Renewable Energy Sources

This work presents an islanded microgrid energy system that uses backstepping control applied to neutral point clamped (NPC) multilevel converters coupled with batteries to behave as virtual generators, able to absorb surplus renewable energy, therefore increasing the penetration of renewable energy sources. Additionally, on a charged battery the virtual generator allows turning-off the backup diesel generator set (GenSet). Aside from improving energy efficiency, the battery-connected multilevel converter aims to regulate frequency, improves power quality, and keeps the microgrid operational in the event of a GenSet failure. The backstepping controlled NPC multilevel converter emulates a virtual generator injecting power to perform as the primary and secondary microgrid frequency controller. Additionally, AC voltage control is implemented, which enables running the islanded microgrid only with multilevel converters, supplied by the battery while integrating solar and wind energy sources. Energy demand and renewable energy forecasts are used to manage the battery state-of-charge. Simulation results, obtained from switched and phasor models show that energy storage and the backstepping frequency control enables the compensation of power fluctuations from renewable energy sources. Furthermore, in the event of the main GenSet failure, the controlled virtual generator keeps the microgrid running for a few minutes, until another GenSet is ready to supply the microgrid. Therefore, the microgrid integration of the battery-connected multilevel converter results in a significant boost in energy efficiency by allowing the disconnection of the backup GenSet.

Multi‐objective optimisation framework for standalone DC‐microgrids with direct load control in demand‐side management

AbstractRenewable energy‐powered DC microgrids have emerged as a sustainable alternative for standalone power systems in remote locations, which were traditionally reliant on diesel generators (DIG) only. To ensure power quality and reliability, energy storage systems (ESS) and demand‐side management (DSM) techniques are employed, addressing the intermittent nature of renewable energy sources (RES). This manuscript presents a novel multi‐objective optimisation framework to determine the equipment sizing, depth of discharge (DoD) of ESS, and share of controllable loads contributing to DSM in a standalone DC microgrid incorporated with RES as a primary energy source and a backup DIG. The proposed optimisation strategy utilises genetic algorithm with the objectives of minimizing lifecycle cost and carbon footprint. A novel battery energy storage system (BESS) management criterion is introduced, which accounts for battery degradation in the lifecycle cost calculation. The minimum allowable DoD of the BESS is considered a decision variable in the optimisation problem to assess the impact of higher DoD on lifecycle cost improvement. MATLAB simulation results demonstrate that the proposed optimisation model significantly reduces the levelized cost of electricity and per unit carbon footprint compared to previous models. Additionally, it identifies an optimal range of DoD for the BESS to enhance the lifecycle cost of a standalone DC microgrid.

A Novel Assimilate Power Flow Control Technique Based Multiport Converter For Hybrid Power Generation System With Grid-Connected Application

Clean, sufficient energy from renewable resources such as the Sun, Wind, and other natural resources is provided via renewable energy technology. Electricity failure also increases with the electricity demand. Thus, consistent loads may be provided by renewable energy sources. A multiport conversion architecture has been developed for hybrid energy sources such as wind and solar sources. A practical method of producing power is to combine wind and sun resources. This study presents a coordinated control method and dynamic modelling tools for an integrated microgrid scheme that combines fuel cell technology, backup diesel generation, photovoltaic systems, battery generators, and assimilated power flow control (APFC). A unique vibrant filter compensator based on dynamics is employed to achieve a fully balanced integrated system. This ensures minimal inrush current, load excursions, and regulated DC bus voltage while optimizing the utilization of the diesel generator set. Our primary area is to achieve the most efficient operation of the integrated renewable energy sources, including PV panels and fuel cells. Photovoltaic Power System with Backup Fuel Cell Source for Hybrid Power System: The control unit in this hybrid system manages the power from both the fuel and the PV cells. When the control power is activated, it triggers the fuel cell and photovoltaic cell powers. The control device first checks if the photovoltaic cell is generating power. If the PV energy is sufficient to meet the load requirements, the control power links the photovoltaic energy to the load. In cases where the load cannot be fulfilled by photovoltaic power alone, the control system disconnects the photovoltaic cell power and switches to the backup fuel cell power. Afterwards, when the power generated from the photovoltaic cells reaches a sufficient level, the control system promptly switches from the fuel cell to the photovoltaic cells. The fuel cell is integrated with a photovoltaic system and a DC-DC boost conversion in conjunction with the resistive workload. The controller outputs have been fine-tuned, and PWM is generated and subsequently supplied to the converter's switching. The converter's design considers conversion efficiency, power sharing, system stability, and responsiveness in various operational scenarios to ensure successful operation. The effectiveness of the simulated output APFC techniques is evaluated for each parameter, such as steady-state error, THD, and the system's efficiency.

COMBINED ENERGY SYSTEMS BASED ON RENEWABLE ENERGY SOURCES

Ensuring the quality of energy supply to remote regions is relevant for grid companies and the state. One of the solutions to this problem is the use of renewable energy sources to generate electrical energy. Given this, the article considers an integrated approach to designing combined autonomous energy systems of an individual residential building based on renewable energy sources with the complete replacement of traditional energy carriers. In addition to the combined power system, the proposed solution implies using an insulated facade of the building, which will reduce heat loss by 1.5 times, compared with an un-insulated building. to increase the reliability of the energy supply, the project provides for a wind power plant, a backup diesel generator station and a battery pack with an inverter. Estimated calculations have shown that the probability of failure of the power system of this configuration is 3%. The conducted ecological and economic justification of the use of an autonomous combined power system allows us to conclude that 2.1 tons of conventional fuel per year is saved and the payback of the energy supply system for a period of up to 8 years.

Techno-economic and environmental impact assessment of a hybrid renewable energy system employing an enhanced combined dispatch strategy

Developing countries face challenges in maintaining a reliable power supply due to factors such as ageing infrastructure and rapid urbanization. Relying on backup diesel generators during outages is not only ecologically hazardous but also economically inefficient. Integrating multiple renewable sources with conventional energy systems is crucial to meeting growing energy demands and reducing carbon emissions. This study assesses dispatch strategies for optimal operation in hybrid renewable energy systems (HRES) connected to an unreliable national grid (GRD). An enhanced combined dispatch (ECD) strategy is introduced for effective energy distribution, considering load demands, energy resource availability, and grid unreliability. Compared to load following (LF) and cycle charging (CC) strategies, the ECD strategy proves superior, resulting in an optimized HRES configuration with a 248 kW solar PV array, a 2 kW wind turbine (WDT), a 22 kW biogas generator (BGG), a 92 kW diesel generator (DiG), and a 658 kWh battery storage (BSS). Achieving a low Levelized Cost of Energy (LCOE) at 0.148 USD per kilowatt-hour and a Net Present Cost (NPC) of 1.99 million USD. Adopting the ECD strategy also exhibits substantial reductions in CO2, CO, SO2, and NOx emissions when compared to CC and LF. ECD achieves approximately 25% lower CO2 emissions, 34% lower CO emissions, and a 40% reduction in SO2 and NOx emissions. These findings highlight the ECD strategy's potential for effective, economically viable, and environmentally conscious energy solutions, particularly relevant in developing nations like Nigeria, where Hybrid Renewable Energy Systems could play a crucial role in the energy sector.

Optimizing Hybrid Photovoltaic/Battery/Diesel Microgrids in Distribution Networks Considering Uncertainty and Reliability

Due to the importance of the allocation of energy microgrids in the power distribution networks, the effect of the uncertainties of their power generation sources and the inherent uncertainty of the network load on the problem of their optimization and the effect on the network performance should be evaluated. The optimal design and allocation of a hybrid microgrid system consisting of photovoltaic resources, battery storage, and a backup diesel generator are discussed in this paper. The objective of the problem is minimizing the costs of power losses, energy resources generation, diesel generation as backup resource, battery energy storage as well as load shedding with optimal determination of the components energy microgrid system include its installation location in the 33-bus distribution network and size of the PVs, batteries, and Diesel generators. Additionally, the effect of uncertainties in photovoltaic radiation and network demand are evaluated on the energy microgrid design and allocation. A Monte Carlo simulation is used to explore the full range of possibilities and determine the optimal decision based on the variability of the inputs. For an accurate assessment of the system’s reliability, a forced outage rate (FOR) analysis is performed to calculate potential photovoltaic losses that could affect the operational probability of the system. The cloud leopard optimization (CLO) algorithm is proposed to optimize this optimization problem. The effectiveness of the proposed algorithm in terms of accuracy and convergence speed is verified compared to other state-of-the-art optimization methods. To further improve the performance of the proposed algorithm, the reliability and uncertainties of photovoltaic resource production and load demand are investigated.

Techno-Economic Energy Optimization of the Off-Grid Electrical System with Power to Gas Storage Technology

Renewable energy sources (RESs) have undeniable advantages over the recent years not only to supply electrical demand but also electrical demand. However, maximum use of the RES’s power has always been challenging as high penetration of the RESs as well as their intermittent nature might compromise the distribution networks power flow constraints. This paper proposes optimal energy operation of the off-grid distribution network (DN) with participation of the power-to-gas (PtG) storage system. In this regard, PtG system is considered as an energy supplier in the DN. The natural gas generated by using PtG is applied to backup diesel generators for meeting demand at peak times. The objective functions in the system are modeled based on technical and economic modeling including minimize the operation cost and maximize the system reliability. The optimal energy operation in the two case studies is assumed considering non-participation and participation of the PtG system. To solving of the energy optimization, particle swarm optimization algorithm is proposed. Finally, proposed case studies under numerical simulation are implemented for validation of the participation of the PtG system.

Design Optimization and Analysis of on-Grid Hybrid Renewable Energy System for Audio-Visual Chain

Rapid advancement of various renewable energies (especially wind and solar energies) as well as energy storage technologies dramatically changes the current energy configuration including the television buildings. In this paper, a micro-grid with high penetration of clean energy systems has been designed for an audio-visual chain. The design and performance optimization of on-grid hybrid renewable energy system using hybrid optimization software is developed and analyzed. The micro-grid design containing photovoltaic panels, wind turbines and storage batteries connected to the grid with a backup diesel generator. The technical and economic advantages of a micro-grid based on clean energy sources for an audio-visual chain located in Tunisia is presented to improve the performance of industrial buildings by providing a green environment with alternative energy sources to meet the high energy demand. This analysis is accomplished by studying solar and wind energy potentials and by aggregating data from various sources. The system was analyzed using HOMER software, which simulate and optimize the proposed micro-grid to a specific demand (audio-visual production chain) with a sensitive/normal loads and energy sources. For the economic analysis, the net present cost was used as objective function in the optimization process. The obtained results show that, in the selected configuration of micro-grid, 49.4% of all energy is supplied by renewable sources with a Total Net Present Cost of $5.02 M under a minimum COE of $0.0609/kWh.

On the design and optimization of distributed energy resources for sustainable grid-integrated microgrid in Ethiopia

This paper presents a study that focuses on alleviating the impacts of grid outages in Ethiopia. To deal with grid outages, most industrial customers utilize backup diesel generators (DG) which are environmentally unfriendly and economically not viable. Grid-integration of hybrid renewable energy systems (HRES) might be a possible solution to enhance grid reliability and reduce environmental and economic impacts of utilizing DG. In this study, an optimization of grid integrated HRES is carried out for different dispatch and control strategies. The optimal power supply option is determined by performing comparative analysis of the different configurations of grid integrated HRES. The result of the study shows that grid integrated HRES consisting of photovoltaic and wind turbine as renewable energy sources, and battery and hydrogen as hybrid energy storage systems is found to be the optimal system to supply the load demand. From the hydrogen produced on-site, the FC generator and FCEVs consume 143 620 kg/yr of hydrogen which is equivalent to 394 955 kg/yr gasoline fuel consumption. This corresponds to saving 1 184 865 kg/yr of CO2 emissions and 605 703 $/yr revenue. Besides, this system yields 547 035.4 $/yr revenue by injecting excess electricity to the grid. The study clearly shows the economic and environmental viability of this new technology for implementation.

Optimized Sizing of Energy Management System for Off-Grid Hybrid Solar/Wind/Battery/Biogasifier/Diesel Microgrid System

Recent advances in electric grid technology have led to sustainable, modern, decentralized, bidirectional microgrids (MGs). The MGs can support energy storage, renewable energy sources (RESs), power electronics converters, and energy management systems. The MG system is less costly and creates less CO2 than traditional power systems, which have significant operational and fuel expenses. In this paper, the proposed hybrid MG adopts renewable energies, including solar photovoltaic (PV), wind turbines (WT), biomass gasifiers (biogasifier), batteries’ storage energies, and a backup diesel generator. The energy management system of the adopted MG resources is intended to satisfy the load demand of Basra, a city in southern Iraq, considering the city’s real climate and demand data. For optimal sizing of the proposed MG components, a meta-heuristic optimization algorithm (Hybrid Grey Wolf with Cuckoo Search Optimization (GWCSO)) is applied. The simulation results are compared with those achieved using Particle Swarm Optimization (PSO), Genetic Algorithms (GA), Grey Wolf Optimization (GWO), Cuckoo Search Optimization (CSO), and Antlion Optimization (ALO) to evaluate the optimal sizing results with minimum costs. Since the adopted GWCSO has the lowest deviation, it is more robust than the other algorithms, and their optimal number of component units, annual cost, and Levelized Cost Of Energy (LCOE) are superior to the other ones. According to the optimal annual analysis, LCOE is 0.1192 and the overall system will cost about USD 2.6918 billion.

Application of an Independent Temporary Spent Fuel Storage Pool Cooling System for Decommissioning of Pressurized Water Reactor Kori Units 3 and 4

The operating license of Kori units 3 and 4 are to be expired in 2024 and 2025. If the plants are decided to be decommissioned, the spent nuclear fuels in the spent fuel storage pool (SFP) have to be removed from the site. However, no proper storage facility is currently available in Korea. To overcome the difficulty, this study proposes application of an independent temporary SFP cooling system. It is expected to safely isolate the SFP from the plant. The case study conducted showed this concept is achievable and technically mature. Moreover, the installation cost per unit is USD 9.51 million obtained from an analogous estimating. This is much lower cost than the dry cask options. Then, system requirements and applicable design are developed. Maximum heat generation of unit 4 is estimated as 1.67 MW, through fuel characteristics categorizations and ORIGEN calculations. To remove the decay heat, installation of an indirect air-cooled method is selected by evaluating three cooling methods. The modification includes new heat exchanger, secondary cooling pumps, and chillers. Furthermore, two single failures are considered; cooling pump and normal power. This can be covered by two redundant trains and a back-up diesel generator provided.

Programming of marine engineers' simulator training

Continuous improvement of the technical equipment of sea vessels is inevitably accompanied by the development and complication of the training base for marine specialists. Simulator training based on a computer model of operating the units of the liquefied natural gas tanker of the Veliky Novgorod type includes interactive computer programs for learning management, created using the e-Tutor computer module included in the simulator delivery set. In the course of systematizing the experience of using specialized programming tools for educational and research activities of students in organizing and conducting simulator training for electrical engineers on computer simulation models of sea vessels, a system of conventional graphic symbols for the elements of the flowchart of the training exercise program has been formed and their description has been given. Training and control exercises include familiarization with the mnemonic diagrams of the integrated marine vessel automation system and assessment of the state of the ship's electrical power system with their help, starting the propulsion electrical installation, providing energy to the operating propulsion electrical installation under load changes, switching on the backup diesel generator unit for parallel operation with the network in normal and emergency modes, acceleration of the vessel to the given speed in accordance with the tasks of the instructor. The advantages of training programming using the e-Tutor computer module are the ability to use the simulator in self-study mode with automated teaching support.

Optimal resilient operation of smart distribution network in the presence of renewable energy resources and intelligent parking lots under uncertainties

Due to climate changes, the occurrence of low-probability but high-impact disasters such as hurricanes, earthquakes, thunders and etc are increasing. So in the occurrence of these disasters, the resilient operation of smart distribution networks (SDNs) needs to be more investigated by researchers. To address this challenge, in this paper, the optimal resilient operation of the SDN in the presence of renewable energy resources (RERs) and intelligent parking lots (IPLs) is investigated. A hybrid stochastic-IGDT approach is developed to handle the uncertainties of the proposed model. So to do this, the stochastic method is used to modeling of RERs generation, electricity price, and EVs (arrival time, departure time, and initial energy) uncertainties. Also, due to the high impact of load uncertainties on the resilient operation of SDN, the information gap decision theory (IGDT) approach is applied to mitigate the uncertainties of load. In this paper, backup diesel generators (BDGs), battery energy storage systems (BESSs), and demand response programs (DRPs) are suggested to improve the resilient operation of SDN. In order to show the efficacy of the proposed model, four case studies are evaluated on a modified IEEE-33 bus test system. The numerical results indicate, in the risk-averse strategy, the SDN is robust against 7.2% increasing active load by having 10% more operation cost, and the resiliency of the system decrease 3.05% for the worst scenario. On the other side, in the risk-taker strategy, with decreasing 7.4% in active load, the operation cost decrease 10%, and the resiliency of the system increase 4.93%.

Pumped Hydro- Energy Storage System in Ethiopia: Challenges and Opportunities

The shares of RE sources are rising because of global warming concerns and the depletion of fossil fuels. However, due to its intermittent nature sustainable power supply depends on the proper energy mix and energy storage. By 2025, Ethiopia has planned to export 24 TWh of energy. Accordingly, its power generation is incorporating different RE sources dominated by hydropower. This paper has reviewed the global up-to-date status of PHES and Ethiopia’s current energy situation and potential PHES. The objective of this paper is to show Ethiopia’s potential for PHES and serve as a “Green Battery’’ for the East Africa Power Pool (EAPP). The review shows that PHES can easily replace backup diesel generators used as a backup during a blackout. Moreover, it showed the Policy barrier for energy storage in the Ethiopian National Energy Policy proclaimed in 1994 and its 2012 updated policy. Thus, Ethiopia’s energy policies need to consider PHES in its energy storage strategy while expanding its generation.

Microgrids as a mechanism for improving energy resilience during grid outages: A post COVID-19 case study for hospitals

The high number of natural disasters in recent years, combined with the emergence of COVID-19 and the pressure it has exerted on healthcare services, has led to the need to guarantee the power supply to critical infrastructures. In this context, ensuring critical loads of hospital has become a mandatory task. Thus, the aim of the work presented here is to improve the energy resilience of a hospital through the installation of a microgrid consisting of a photovoltaic system working together with a diesel generator in the energy resilience scenario. In the first scenario, it has been evaluated how a microgrid es economically viable for the case where there is no grid outage. In the second scenario, the microgrid has been optimised taking into account both the economic profitability and the ability to withstand a 24-h outage in the month of lowest radiation. The results obtained have shown that the microgrid consisting of a PV system, an energy storage system and a backup diesel generator was able to withstand an average outage time of 72 h, providing the hospital with a net gain of 24 h in terms of energy resilience compared to the business as usual (BaU) and a reduction in utiliy cost of $ 147,354.

Stand-alone micro-trigeneration system coupling electrolyzer, fuel cell, and heat pump with renewables

A micro hydrogen system in conjunction with renewable energy, namely a wind turbine, a photovoltaic array, and an air-source heat pump, is designed to satisfy the power, heating, and cooling needs of a stand-alone household in a Mediterranean climate. An hourly-based model is used to simulate its operation throughout the year. A unique power management strategy is applied to achieve optimum configuration and size of the components without shortage or excess energy. Unlike previous practices, there is no release of excess heat into the environment. An innovative combination of a fuel cell and a heat pump followed the household's electrical and thermal (domestic hot water/heating and space cooling) profile. Almost 80% of the energy for preparing hot water and household cooling/heating was obtained from waste heat from these devices. The system is compared to the most commonly used stand-alone hybrid renewable energy system with battery storage. The hydrogen system needs four time less batteries and it does not need a back-up diesel generator. Although the energy storage in batteries is more efficient than in hydrogen, the hydrogen system requires only 10% larger primary energy input than the system with only battery storage.

Distributed Energy Resource Control and Utility Interconnection Management: Implementation in a Distributed Microgrid

This article describes the implementation of a brownfield microgrid with the upgrade of existing distributed energy resources (DERs), design of the medium-voltage (MV) interconnection, and implementation of a microgrid control system to meet the U.S. Department of Defense (DOD) needs at Fort Custer, Michigan. Brownfield microgrids involve complexities in design, integration, and commissioning but offer better economic viability due to reduced capital cost upfront. This work tries to identify the challenges associated with brownfield microgrids and provides systematic practical solutions to mitigate them. As part of the upgrades, backup diesel generators were retrofitted to support grid-parallel operation. A battery energy storage system (BESS) was newly installed to manage intermittencies for the existing solar generation and to support the microgrid. The individual DER assets were integrated in a two-level hierarchical microgrid control architecture and controlled in a coordinated manner to achieve seamless islanding and reconnection with the utility grid at the point of common coupling (PCC). The article provides the field data demonstrating the improvement in resiliency through islanded operation as well as maintaining power quality when operating in parallel with the utility. The economic operation of the assets and participation in utility ancillary services were also key goals achieved through the microgrid. This ability allows the military to reduce its total cost of ownership to achieve its mandated energy security needs.

Selection of the best dispatch strategy considering techno-economic and system stability analysis with optimal sizing

In this paper, optimized hybrid off-grid renewable energy systems (HRES) have been designed for two divisional locations in Dhaka and Khulna in Bangladesh. An analysis is conducted using five different load dispatch strategies to find the best dispatch strategy for a cost-effective and technically feasible Islanded hybrid microgrid that will support the growing power demand. A comparative analysis among the various dispatch strategies is also presented to find out the best and worst dispatch strategies for the proposed HRESs. The two HRESs consist of solar PV, a backup diesel generator, wind turbine, load demand of 23.31 kW, and a battery storage system. HOMER predictive strategy, Generator Order, Load Following, Combined Dispatch, and Cycle Charging dispatch strategy has been adopted for evaluation. The two HRESs are optimized for CO2 emission, Levelized Cost of Energy, and Net Present Cost minimization along with a feasible and stable voltage-frequency response on basis of the five dispatch techniques. The techno-economic analysis of the two HRESs is conducted using the HOMER Pro software platform. For the power system response analysis, MATLAB/Simulink is used. This study provides a complete guideline for determining the optimum component sizing ensuring optimum operation and possible costing estimation for the optimized performance of the two HRESs for different dispatch techniques. Also, a comparative study among the designed HRESs, other hybrid systems, and conventional power plants is conducted to prove the significance of this research work.

Research of the operation of an autonomous electrical complex with a combined composition of backup power sources

THE PURPOSE. To analyze scientific and technical information and practical experience of the functioning of autonomous electrical complexes with asynchronous electric motors in the composition. To develop a mathematical model of an autonomous electrical complex of a drilling rig with the presence of an active rectifier, an inverter with pulse-width control signals, as well as combined backup power sources – a battery and a diesel generator set. To establish the influence and expediency of using a combined composition of backup power sources on reliable operation and the possibility of overcoming the voltage failure caused by a sharp increase in load in the steady-state operation of an autonomous electrical complex. METHODS. For the successful fulfillment of the tasks set, this study applied the methods of mathematical modeling of power supply systems, methods of simulation modeling, the theories of automatic control, automated electric drive, and electrical circuits. Also, in research used the MATLAB software package with the built-in Simulink graphic modeling environment to create a mathematical computer model and to process the data obtained analytically. RESULTS. The article describes the relevance of the research topic. The study provides criteria for choosing the composition of backup power sources. Mathematical and simulation models of an autonomous ETC have been developed according to the “power source-frequency converter-industrial load” scheme, taking into account the influence of a non-linear load on the specified power quality indicators. The study has developed the structure of an autonomous electrical complex with a combined composition of backup power sources, which allows to overcome the voltage drop in the network caused by a sharp load surge, while ensuring the required indicators of electricity quality. CONCLUSIONS. The use of a rechargeable battery makes it possible to increase the overload threshold of the main diesel generator set regulated by GOST R 53987-2010 from 30% to 60%, as well as to ensure reliable connection of a backup diesel generator set without interrupting technological processes.

Optimization of stand-alone and grid-connected hybrid solar/wind/fuel cell power generation for green islands: Application to Koh Samui, southern Thailand

This paper presents the optimization of stand-alone and grid-connected hybrid power generation systems for green islands, with application to Koh Samui in southern Thailand. A techno-economic optimization analysis is applied using the Hybrid Optimization Model for Electric Renewable (HOMER) Pro simulation tool. Four scenarios are identified to select the most suitable solution for a hybrid renewable energy system (HRES) integrating solar photovoltaic (PV), wind turbine generator (WTG), fuel cell (FC), and battery energy storage (Li-Ion), with backup diesel generation or grid connection with the mainland as options. The NASA-SSE and MERRA databases are used as inputs to analyze the solar and wind energy potentials, respectively. The results show that the levelized cost of energy (LCOE) of the HRES with a grid connection to the mainland (Scenario 3) has the lowest LCOE (0.132 US$/kWh), but at large greenhouse gas (GHG) emission costs (20.5 ktonnes/year) due to the high carbon intensity of Thailand’s power portfolio. A stand-alone, 100% renewable energy system (Scenario 4) includes a PV capacity of 182 MW, a wind power capacity of 8 MW, a fuel cell system of 10 MW, a 17.9 MW power converter, and 211 MWh of battery storage. The net present cost (NPC) of this system is 542 MUS$ and the LCOE is 0.309 US$/kWh, with 89% of the energy generated by the solar PV system. Therefore, a 100% renewable energy-based microgrid system is possible on Koh Samui as it can provide a more suitable and reliable solution when considering a HRES system for the total load demand (104 MW of peak load) of the island. Finally, the economic analysis also reveals that the investment in a HRES system is feasible as the payback period is 9 years under an internal rate of return (IRR) of 10% and an appropriate Feed-in-Tariff (FiT) of 0.385 US$/kWh.