1. Introduction
The provision of electric energy to remote and isolated regions is crucial for enhancing livelihoods and fostering economic growth, thereby facilitating development in these areas. A rural electricity study in India was presented by Rajbongshi et al. [
1], which was observed to reduce energy costs when connected to the grid system. When there is a capacity shortage from the hybridized energy network or peak energy (hourly) demand, the grid system can supply the deficit power through grid purchases. The electric energy cost reduced to USD 0.0640/kWh from USD 0.1450/kWh according to the authors’ report study. An examination of various architectures of hybrid energy networks in the Harbin housing estate, situated in a cold climate in China, reveals that global solar insolation influences the valuation of electric energy flow. Additionally, the current fractional values of the fossil fuel generator (diesel) within the solar–diesel hybrid energy system are also impacted. The utilization of fossil fuel power plants and the expansion of grid systems represent conventional methods for generating and supplying electricity to remote and isolated regions. However, these approaches are increasingly viewed as less viable alternatives due to the global depletion of fossil fuel resources and the challenges associated with transporting these fuels to distant areas, which also contributes to environmental pollution. Additionally, extending grid services to isolated communities may prove to be economically unfeasible due to the substantial capital investment required [
2]. The implementation of clean energy facilities has garnered significant interest due to the advantage of reduced emissions on a global scale. However, the inherent instability and unpredictability of renewable sources, such as solar PVe (photovoltaic) and wind turbine systems, along with their respective resources (solar insolation and wind velocity), have raised concerns regarding the oversizing of components to ensure the reliability of energy systems, consequently leading to increased costs in power systems. To address these challenges, integrating renewable energy sources that combine various alternative resources with energy storage or a backup fossil fuel power plant can enhance cost estimation and reliability of generation sources for remote or isolated villages that have limited or no access to the grid. The distance from the energy source to the load has an economically feasible impact on a modeled system comprising diesel plants, batteries, and solar generators, which has demonstrated greater power reliability and economic feasibility compared to traditional fossil fuel (diesel) generators, studied by Odou et al. [
3]. An examination and review of integrated renewable energy sources in both off-grid islands and grid integration was conducted, focusing on their various architectures, optimization methods, and planning strategies [
4]. In developing nations, numerous alternative energy sources for electrification in isolated or remote regions have been established, employing integrated island or off-grid systems [
5]. A comprehensive off-grid biogas generator and solar PVe system was developed to provide a dependable electricity supply for both residential areas and agricultural activities in a small village in Pakistan [
6]. Previous research has primarily concentrated on a singular energy system within a specific location, lacking comprehensive discussion and analysis of the potential capacity and flexible hybrid alternative energy systems proposed for various scenarios. This is particularly relevant to external infrastructural conditions that may differ when interfaced with the grid system.
A grid integration system combining biogas generators, solar PVe plants, and fossil power plants (diesel) was successfully implemented in a village in Iran through technical analysis and optimization design. Kasaeian et al. [
7] investigated differences in sensitivity to uneven economic conditions, focusing on essential economic indicators like inflation and discount rates, within the enhanced framework of the energy system. The researchers in [
8] introduced a cohesive electro-mechanical–bioprocess system that enhances sludge utilization while ensuring minimal environmental repercussions. This method achieves an impressive recovery rate of organics, with approximately 91.4% net organic carbon, which is efficiently transformed into a unicellular protein with over 63.0% net organic carbon through a sequential process. A thorough life cycle and technological/economic assessment validates the significant environmental and financial advantages of this method. Importantly, it leads to a 99.5% reduction in carbon (IV) oxide emissions and a 99.3% reduction in energy consumption compared to the traditional anaerobic breakdown process. Merabet et al. [
9] conducted a comprehensive review highlighting their key finding regarding the viable generation of hydrogen gas as a sustainable energy transition derived from various wastewater treatment technologies, including electrochemical, biological, and advanced oxidation methods. The core objective of their review is to mitigate the carbon intensity associated with emissions from fossil energy sources. Quan Lee et al. [
10] reported an electrical reformation of waste generated from sugarcane bagasse to produce essential compounds and sustainable hydrogen gas. The electrical reformation process is powered by a solar PVe generator by introducing a secure and low carbon intensity pathway to produce sustainable green hydrogen gas and chemicals derived from raw biomass materials. Nguyen et al. [
11] and associates conducted a study on the generation of sustainable green hydrogen gas through pyrolysis and gasification technologies, focusing on the efficiency, technical challenges, and mechanisms associated with these processes. They highlighted the transformation of biomass waste into green hydrogen gas, achieving a production efficiency ranging from 40.0% to 60.0% with a high heating value. Their study also offers an overview of optimized conditions to maximize the yield of green hydrogen gas and the volumetric composition percentages of various types of biomass waste. The growth in the production of municipal solid waste (which includes non-liquid waste from households, individuals, hospitals, schools, and similar sources) and non-municipal solid waste (comprising significant waste categories from industrial, mining, and agricultural activities) is linked to the increase in the global population. The accumulation of waste materials, especially food waste, is primarily due to densely populated regions that draw in tourists [
12]. The agricultural sector faces significant challenges due to the large quantities of biodegradable materials and agricultural waste, rendering them unsuitable for human consumption and livestock byproducts. The estimated annual global waste production is between 7.0 × 10
9 and 9.0 × 10
9 tons, exceeding the 2.0 × 10
9 tons of municipal solid waste produced each year [
13,
14]. With expected production projected to attain a value of 3.40 × 10
9 tons/year by 2050. Close to 33.3% of food production for consumption by humans was discarded with an estimated value of 1.30 × 10
9 tons yearly [
15]. In contemporary societies, the challenge of waste management has garnered significant attention, focusing on minimizing the accumulation of waste in landfills, enhancing waste segregation as an evolving practice in developed nations, and facilitating more cost-effective and accessible recycling processes. Most biological wastes are compostable and can undergo a natural decomposition and burning process. The byproduct of treating industrial wastewater and municipal wastes is waste sludge generation, which requires disposal. Irrespective of reducing wastes effectively and wastes ending up in landfills, conventional processing methods can have several adverse effects on the human environment, including the effects of greenhouse emissions and soil, groundwater, and air contamination. The waste-to-energy conversion (formation of gases) technique is one of the atmospheric-friendly management processes of wastes by which wastes from biodegradable substances are processed into gas (biogas) by an anaerobic breakdown (digestion) reaction. The biogas power plants utilize biomass resources efficiently, reduce CO
2 emissions, make energy that is friendly to the environment, and impact the environment in an economically favorable way. In general, accepting biogas power plants from residential areas is welcoming; however, the harmful effect due to generally accepting the biogas system arises from odors, which are not pleasant within the biogas power plants’ vicinity, the hazardous nature of the odor, noise pollution, food production causing competition, and traffic [
16]. Generally, raw biomass materials for biomass gasifier plants can be categorized into six components, namely, animal wastes, field/garden wastes, organic industrial wastes, municipal solidified wastes, food wastes, and sludge. Bioenergy can be beneficial to the environment if feedstocks are sustainable and there is no competition with the production of food and biodiversity’s negative impacts [
17]. Capturing carbon/utilization/storage can reduce emissions of carbon dioxide (CO
2) from the generation of fuel and hydrogen gas with low carbon.
Baruah et al. [
18] analyzed the economics and technical operation feasibility of a modeled autonomous hydrokinetic/photovoltaic/battery/biogas/wind generator by applying HOMER PRO smart grid simulation/optimization tools to determine the production energy for Sikkim, an eastern district of India with the lowest levelized energy valuation of USD 0.095/kWh, overall current cost of USD 5 million, and annual gas emissions of 995,709 kg/year. Zhou et al. [
19] focused on designing a battery/diesel generator/biogas plant/wind turbine stand-alone smart grid network with a discussion on issues of dispatch, operation, and energy management features. The controllable biogas plant and wind turbine were localized to monitor fluctuations from load over a lengthy timescale to reduce the production of power from the diesel generator and the maximum demand shifting request of the storage system (battery banks). Singh and Basak [
20] proposed a concept and evaluated a small-scale rice straw-referenced microgrid system economically and technically that utilized excess rice straw from a village (900 acres of cultivated land and 250 houses) for electric production. The proposed system can process 1128 tons of excess rice straw annually and feed the community’s energy demand. The rice straw was processed by a gasification technology, which was incorporated with a utility grid/battery/solar PVe system. The levelized electricity cost of the designed microgrid (biogas/battery/utility grid/solar PVe) system was USD 0.089/kWh. Ribo-perez et al. [
21] applied HOMER power software to build biogas generator modules, including economic and technical operation parameters for simulation. In fueling energy generation through synthetic gas production from a downdraft biogasification plant, rural communities of Zambia and Honduras were used as case studies to demonstrate the procedure’s viability. Odoi-Yorke et al. [
22] utilized a proposed battery/biogas plant/solar PVe system to energize remote communities of Ghana and discovered that their proposed system generated USD 0.256/kWh of levelized electric costs, which was more than the household residents of Ghana’s levelized electric costs by 64.0%. They (the authors of [
22]) also noticed that their proposed system was more efficient in performance than the battery/diesel plant/solar PVe and independent diesel generator systems, considering emissions and costs as factors. Tostado-Veliz et al. [
23] developed an innovative unified diesel generator/biogas plant/solar PVe optimal system in off-grid operation for isolated regions with biomass waste potential. They observed that the cost of the implementation of the unified microgrid system was reduced by 90.0% through the biogasifier system. They also noticed an 83.0% reduction in the net carbon (IV) oxide emissions in comparison to the conventional sources (diesel plants) applied as a reference or baseline system, which generated a 33.0% increase in the net project valuation, as the biomass price increased from USD 0/kg to USD 0.4/kg within the feasible econometric sensitivity performance.
Loboichenko et al. [
24] reviewed the issue of the structure of potential biogas microgrids (energy production networks) in detail. They noticed that the production potential of the biogas microgrid networks generated a daily energy of 5.0 MWh/day. The biogas plant contributed an overall energy capacity ranging from 1.0% to 67.0% to the microgrid network. Santos et al. [
25] presented a hybrid thermal generator/bio-digester/grid/battery microgrid network that produces biogas fuel from the bio-digester to fuel the thermal generators for electric production to be consumed by the load. The biogas fuel was upgraded to generate bio-methane. The designed microgrid model by the authors generated low operating costs of BRL 1170.99 and BRL 345.69 during weekdays and weekends with a limited biogas fuel production of 490 kWh, insufficient for electro-mechanical energy demand. Amorim et al. [
26] proposed an integrated cardinal non-linear programming algorithm to integrate a unified distribution of microgrid generation (biogas generator/wind power/solar photovoltaic panel network) to manage the unstable renewable sources with local regulation compliance in Brazil. The application of cluster technology and efficient time-sensitive model analysis to the proposed microgrid network against load variation reduced its overall energy cost by 45.0%. The authors also discovered that an organized systematic model could fulfill 100% of the energy and heated water demand through all scenarios when crucial roles are played by customized incentives to reduce energy costs and promote energy sustainability. Jabbary et al. [
27] investigated the utilization of optimal local biogas fuel production in multiple-energy generation sources of a photocell/micro-turbine/biomass plant/wind turbine/gas network feed/grid/battery cell network by adopting GAMS energy analysis software. The operating costs of the microgrid system were reduced significantly to 46.0% with a value of USD 2800/day. The energy transfer or power flow between the micro-hubs’ local network was also reduced significantly, by 39.40%. The micro-hubs’ local energy supply cost for the off-grid operation was reduced by USD 1400/day (34.0%) compared to its normal operation mode. Kumari et al. [
28] addressed the unstable frequency operation of a microgrid system comprising a solar PVe cell/biogas plant/grid/Li-ion battery network. The unstable inertia of the microgrid network was caused by the low generating capacity of the biogas plant. The adoption of the permanent magnetization of a synchronous machine (PMSMA) with a bidirectional AC/DC/AC power converter was used to connect the biogas generator to the microgrid network. The PMSMA machine and bidirectional AC/DC/AC power converter maintained a stable frequency between the biogas plant and microgrid system, which was verified through the output result of the OPAL/RT simulator system. Sengupta et al. [
29] considered a modeled biogas plant/wind plant/solar PVe cell/grid microgrid system that utilizes a physics-referenced model to determine the power generation capacity of the solar PVe system in a soiled state. The output result of the solar PVe recorded an estimated error of ±6.50% from its energy value and an estimated error of ±6.00% between the power estimated and power measurement value of 10.0 kWp. The soiled state of the solar PVe system generated a power of 5.10 kW, and the wind turbine generated a power value of 90.0 W by importing 74.0 W from the grid system, causing a drop in the solar PVe generation to 3.80 kW and requiring an imported power of 2.10 kW from the grid system and increasing the cost of operation from 22.0 Rs to 24.0 Rs for a clean soiled state. Miah et al. [
30] developed a unified system of a solar PVe cell/biogas generator/battery microgrid network with five topmost feasible architectural operations to mollify diesel fuel consumption for 0.620 acres of agricultural land with an overall pump capacity of 8.0 kW for a canvas system. The microgrid network generated a daily energy value of 11.520 kWh/day for the main energy consumption and a peak capacity of 10.290 kW. Minimizing the over-consumption of diesel fuel from BDT 45.0/liter to BDT 65.0/liter. The microgrid system generated an annual energy of 7760 kWh beyond the annual main energy demand of 4205 kWh. Ali et al. [
31] developed an optimal microgrid network of a solar PVe cell/biogas generator/grid system/wind turbine system for a five-story residential apartment in Bangladesh (Rajshahi) using a HOMER software simulation. The configuration of the biogas generator/solar PVe/grid generated a renewable fraction of 59.40%, an energy cost reduction of USD 0.0306/kWh, a reduction in carbon (IV) oxide gas emissions of 46.0%, an annual cost of operation (USD 1187.00), and net current valuation of USD 46,813.00. The configuration generated an annual energy of 3040 kWh/year from the biogas generator and an annual energy of 31,168 kWh/year from the solar PVe cell, with a grid sale and grid purchase record of 13,411 kWh/year and 21,951 kWh/year. Annual energy savings of 2730.44 kWh/year were achieved through a strategy of demand response, causing a reduction in the conventional grid reliance, attaining high reliability, enhanced accuracy of the estimated power generation, and a non-supply (negligible) energy of 4.310 × 10
−14 kWh, with a power supply waste probability of 1.060 × 10
−18. Miracle et al. [
32] modeled an optimal wind turbine/biogas generator microgrid system through the application of an optimal particle orientation cat swarm method and MATLAB Simulink to generate the lowest net current value and a feasible high penetration of power production from the biogas plant. The adopted method by the authors attained a biogas energy cost of USD 0.0267, wind energy cost of USD 0.4016, optimal particle swarm value of USD 0.3798, and optimal cat swarm value of USD 0.0397. The optimal particle orientation cat swarm method attained a minimum energy cost of USD 0.00018 with the wind energy, and the optimal particle swarm and optimal cat swarm achieved cost values of USD 0.0022, USD 0.0018, and USD 0.0005, respectively. Orellana-Lafuente et al. [
33] conducted a technological–econometric estimation of biogas fuel production from the treatment of an anaerobic wastewater plant system in Bolivia (Cochabamba). A mean value of 7859.07 Nm
3/day of biogas fuel was produced with a base output power of 300 kW, generated as the topmost power savings, annually, showing that biogas fuel production from the treatment of anaerobic wastewater plant system is a feasible, clean, and non-seasonal energy source (in conclusion). Fu et al. [
34] proposed an optimal synergistic approach for an agricultural microgrid network and greenhouse operation. The agricultural microgrid is a system of micro-organism/solar PVe cell/biogas generator/grid/gas boiler networks in China (Qingdao city). The authors confirmed the optimal synergistic approach across the environmental, energy, and agricultural sectors as being effective in boosting the econometric efficiency and low emissions from the agricultural microgrid operation, facilitating an operating cost reduction of CNY 966.0 and a carbon emission reduction of 2874.0 kg for the microgrid network with a greenhouse footprint (coverage area) of 3500.0 m
2 during a typical winter.
R. Jean et al. [
35] addressed the energy demand of 334 inhabitants of Manoka island community, Douala city, Cameroon, with a daily mean power of 1082.900 kWh/day and a daily maximum power demand of 183.990 kW/day. They assessed the feasible implementation of an off-grid integrated solar PVe cell/fuel cell/wind turbine/biogas generator/batteries/electrolyzer microgrid network to satisfy the demand of the community. By using the HOMER power program software, the research activity of the authors for the proposed 25-year lifespan network generated a low electric cost unit (USD 0.1981) and net current valuation (USD 2,209,741.00). The microgrid network yielded a profit of USD 57,387.00 from a cost-effective connection of 201 batteries with an internal return rate (9.09%), investment return rate (6.19%), and payback time (8.76 years). Jongudomkarn et al. [
36] designed a diesel plant/solar PVe cell/biogas generator/wind turbine/heat pump microgrid network and proposed a control-referenced approach loop system that can adapt to the biogas generator–heat pump to produce constructive inertia to regulate the frequency of the microgrid network, by studying the charging state of the heat energy reserve. The control-referenced approach loop system will optimize the parameters of the constructive inertia to boost the performance of microgrid-controlledlled frequency through optimal discharging or charging of the energy reserve system within its normal operation boundaries. Reddy et al. [
37] modeled a bio-diesel generator/solar PVe/fuel cell/wind turbine/biogas generator/flywheel/battery microgrid network with MATLAB-Simulink sim-scape reference software and proposed a proportionate/intrinsic/derivative control system for the network to stabilize the oscillating frequency produced by the microgrid system when the load varies and the output powers of the wind turbine and solar PVe systems fluctuate. Hoang et al. [
38] modeled and developed a control system for the components of a solar PVe/biogas generator/Li-ion battery microgrid system by applying data manufacturing. They (the authors) incorporated a high-degree control system to sustain the AC and DC buses during the operation of the microgrid system. The biogas generator and lithium-ion storage maintained the voltage degree of the DC bus, while the peak power indicator tracking controller maximized the output power flow of the solar PVe generation. Verma et al. [
39] addressed a crucial demand for a vigorous procedure in restoring the load of an energetic distribution network, by focusing on the application of a biogas generator as a reviving energy source. The researchers recovered a net load capacity of 1.5 MW through the biogas generator application to restore the energy demand operation in the energetic distribution network by formulating the conversion of lindist flow to a hybrid integer linear program model and applying Gurobi-solver software (Gurobi optimizer v12.0.2). Mondal and Sil [
40] detected and analyzed a fault from the short-circuit state of a modeled grid/biogas generator/solar PVe/battery microgrid system. The authors of [
40] discovered that the fault that arose from the three-lines-to-earth (short-circuit) formation of the microgrid network made the voltage bus = 0 with a very high current. Harmonics were injected into the microgrid network after the fault was cleared with the absence of noise in the waveform arrangement of the current flowing in the network. Singh et al. [
41] adopted a vigorous control strategic application for an isolated DC (biogas generator/biomass feedstock/solar PVe) microgrid system that was modeled through MATLAB Simulink sim-scape software. The chosen control strategy for the biogas generator and biomass feedstock system was an observer-referenced sliding mode control system, capable of regulating or synchronizing the voltage of the DC microgrid bus despite fluctuations in load disturbances.
The aforementioned studies conducted by various researchers suggest that the implementation of island and grid hybrid generator systems is more advantageous than that of fossil fuel power plants. In terms of cost efficiency, the initial investment for hybrid alternative energy sources is higher than that of fossil fuel plants. However, the volatility of fossil fuel prices adversely affects fossil fuel generators, while having minimal impact on hybrid renewable generators. Consequently, this leads to a decrease in operating costs.
1.1. Problem Statement
This ongoing experiment focuses on the current energy system technology and the suggested energy network design for the inaugural waste power plant system in the On-nut community, which includes the following aspects: flexible operation of the microgrid network under variable load (energy demand), conversion of biomass feedstock (fuel energy) into electricity, generation of biomass gasifier fractions and their integration into the utility grid network, as well as the performance ratio and economic reliability of the utility grid in conjunction with biogas generators and battery networks.
1.2. Innovation of Experimental Research (Proposal)
The integrated power system, which includes biogas generators, a grid network, and batteries, was developed through an experimental design by the On-nut power plant management sector. It employs a multi-control algorithm within the microgrid system to create viable architectures for the integrated energy system, facilitating optimization and simulation through a sophisticated smart grid analysis network to generate the corresponding energy waveform sensitivity. The aims and objectives of the hybrid energy network are as follows:
To explore and improve the management strategies for variable power generation within existing microgrid technologies (including utility grids and biogas generators) by integrating lithium-ion, flow, and zinc bromide battery technologies with a closed-loop control system, thereby enhancing the flexibility of current power systems.
To assess the optimization of the suggested power generation network (biogas generators/grid/batteries) in terms of the most economically feasible and cost-efficient operation of the biogas generators/grid/Li-ion battery, biogas generators/grid/FB battery, and biogas generator/grid/zinc bromide battery during power flow and energy production services for the On-nut community.
To determine the performance ratio of the current energy system (biogas generator/utility grid) and the proposed energy system’s architecture (biogas generator/grid/Li-ion+ battery, biogas generators/grid/FB battery, and biogas generator/grid/zinc bromide battery), respectively.
The subsequent sections of this experimental research include the methodology outlined in
Section 2.
Section 3 details the establishment of experimental, mathematical, schematic, and simulation models.
Section 4 presents a formal conclusion of the experimental and simulation analyses, accompanied by a critical appraisal.
4. Conclusions
An evaluation was conducted on the existing microgrid network, which includes biogas generators, a utility grid system, and a generator order control system, alongside the proposed microgrid network that incorporates biogas generators, a utility grid, batteries, and load-following and cycle charging control systems for energy production in the On-nut community of Bangkok. This assessment focused on various aspects such as technical efficiencies, operational and generation performances, energy cost management, and performance ratios. The current microgrid configuration achieved a performance ratio of 18.55%, incurred energy charges amounting to USD 173,427.13, and recorded the highest energy purchase at 244,775 kWh per year, with 2.16% sourced from the grid system. It also noted the lowest net energy purchase of −1,734,271 kWh, a renewable fraction of 92.80%, and the highest energy production of 11,307,775 kWh per year. In contrast, the proposed microgrid architectures utilizing lithium-ion, zinc bromide, and flow batteries yielded performance ratios of 78.89%, 80.55%, and 79.65%, respectively, with renewable fractions of 92.90%, 94.20%, and 94.0%. These proposed systems demonstrated reduced energy purchase values of 239,764 kWh per year, 199,331 kWh per year, and 203,765 kWh per year, alongside increased net energy purchase values of −1,719,661 kWh, −1,518,661 kWh, and −1,412,173 kWh from the grid.
Furthermore, the energy charges associated with the lithium-ion, zinc bromide, and flow battery architectures were lower, amounting to USD 171,966.14, USD 151,866.06, and USD 141,217.29, respectively, compared to the current energy system value outlined in
Table 7. From the proposed microgrid architectural system point of view, the zinc bromide architecture generated a higher performance ratio (80.55%) than the other proposed architectures from
Section 3.5. The lithium-ion architecture generated a higher level of technical efficiency in terms of energy production (11,293,764 kWh/year) than the other proposed architectures. The flow battery architecture was the most expensive energy system; see
Table 8.
The analysis indicates that the proposed microgrid system demonstrates greater efficiency compared to the existing energy system, particularly regarding the renewable fraction, performance ratio, energy charge, energy purchase, and net energy purchase.