Hybrid Energy Generation Research Articles

Optimization of grid-connected hybrid renewable energy system for the educational institutes in Pakistan

To foster resilient energy transition systems, the deployment of renewable energy sources is potentially helpful in the acceleration towards sustainable, reliable, and diversified solutions. In this feasibility study, aims to pursuit the best optimal solution for renewable energy resources, integrated into the local university's energy mix, to meet the electrical load demand of 8500 kWhr/day and a peak load of 815 kW. A model of a hybrid grid-connected renewable energy (PV/Biomass/Hydel/Diesel generator/Grid) system was implemented in HOMER software, to obtain the most efficient and cost-effective hybrid energy generation. The outcomes of the simulation seem more viable based on sensitivity analysis, as the cost of energy (COE) for an energy system with a hybrid combination is 0.13.$/kWh, meanwhile energy price with the grid system is 0.18 $/kWh. According to the HOMER analysis, a hybrid grid-connected PV/biomass/hydro system demonstrates both technological feasibility and economic viability, meanwhile it will also save 1575 tons of CO2 per year. Therefore, this proposed hybrid energy system, a step towards sustainable development, can be applied at institutional levels, especially in developing countries.

Thermo-Economic and Environmental Assessment of a Novel SOFC-Based Hybrid Energy Generation System for Combined Cooling Heating and Power Generation

Thermo-Economic and Environmental Assessment of a Novel SOFC-Based Hybrid Energy Generation System for Combined Cooling Heating and Power Generation

A non-isolated converter of switching current stress in DC-DC converter for integrating PV and battery storage system

ABSTRACT High-gain DC-DC converters have seen significant adoption in renewable energy systems like Photovoltaic (PV), Fuel Cells (FC), and other systems. However, their effectiveness is increasingly tied to the availability of renewable resources. As Renewable Energy Sources (RES) typically generate electricity at low voltage levels, integrating high-gain DC-DC converters with RES is crucial for optimal performance. This paper introduces an innovative DC-DC converter design that achieves high gain and is specifically able to integrate smoothly with RES like PV systems and battery storage. The innovation of the proposed converter lies in its integration of conventional boost and buck-boost converters, enabling a high voltage gain while minimizing output voltage ripple and reducing switch current stress. Additionally, its unidirectional power transfer port allows efficient energy flow from solar PV or battery sources to the load, making it highly adaptable for managing fluctuating energy sources, a feature that distinguishes it from current modern converters. Its design simplifies architecture by combining traditional converter types, reducing the number of components, which leads to cost savings, lower weight, and improved reliability. Additionally, the design minimizes output voltage ripple and reduces switching current stress, enhancing the converter’s durability under variable operating conditions. The converter’s performance is evaluated through simulation and experimental studies, demonstrating a 96.3% efficiency and 5.5 times of voltage gain. The converter’s feasibility and effectiveness are validated under dynamic scenarios with varying solar irradiation, making it an ideal solution for clean energy generation systems, including hybrid energy generation setups. The proposed converter topology offers an auspicious solution for high-gain DC-DC conversion in renewable energy systems.

Estimation of hybrid energy generation of solar‐wind tower for electric vehicle charging: A case study of Indian highway

AbstractAdvances in non‐conventional energy technologies and increasing fossil fuel prices along with environmental concerns have made hybrid renewable energy systems important. In view of this scenario, solar panel mounted on a vertical axis wind turbine (called as solar‐wind tower) can be utilized to produce more electric energy than individual one. This solar‐wind tower will be located in the space available between two opposite roads of expressways/highways. Solar‐wind tower located in such a manner that the air velocity produced from driving vehicles on both sides of the road is adequate to cut the turbine blades which will produce unidirectional torque. A battery energy storage system (BESS) stores the power produced by the solar‐wind tower so that it can subsequently be used for local loads and electric vehicle charging stations (EVCS) and remaining energy can be supplied to the grid. In this work, a hybrid system composed of wind and solar is designed and modelled in Simulink (MATLAB) and tested on real data of wind speed and validated by Opal‐RT simulator. From the simulation result, it is estimated that total electrical power output of a single solar‐wind tower is around 15 to 20 kWh in a day under the assumed conditions.

3D printing flexible Ga-doped ZnO films for wearable energy harvesting: thermoelectric and piezoelectric nanogenerators

The 3D printing of energy harvesters using earth-abundant and non-toxic elements promotes energy sustainability and market competitiveness. The semiconducting behavior and non-centrosymmetric wurtzite crystal structure of gallium-doped zinc oxide (GZO) films make them attractive for thermoelectric and piezoelectric nanogenerators. This study investigates the thermal, structural, mechanical, thermoelectric, and piezoelectric properties of 3D-printed GZO nanocomposite films. Thermal analysis demonstrates the stability of the nanocomposite film up to 230 °C, making it suitable for wearable energy harvesters. The crystalline structure of the nanocomposite film aligns with the hexagonal wurtzite structure of ZnO and displays a bulk-like microstructure with a uniform distribution of elements. The presence of Ga 2p, Zn 2p, O 1 s, and C 1 s core levels confirms the development of the nanocomposite film, characterized by a fine granular structure and a conductive domain compared to the neat resin film. The inclusion of GZO nanofillers tailors the stress–strain behavior of the nanocomposite film, enhancing flexibility. The 3D-printed GZO nanocomposite films demonstrate a promising thermoelectric power factor and piezoelectric power densities, along with mechanical flexibility and thermal stability. These advancements hold significant potential for wearable and hybrid energy generation technologies.

Environmental and economic impacts of photovoltaic integration in concentrated solar power plants

This study conducted an environmental and economic assessment of an innovative hybrid energy generation system, a CSP+ plant, which integrates photovoltaic (PV) panels in a concentrated solar power (CSP) setup. The CSP+ concept uses a beam splitter that transmits part of the incident solar spectrum towards the PV cells for electricity generation and reflects ultraviolet and infrared light to the receiver tube for heating. This system allows more efficient use of solar radiation in a compact system with optimal efficiency.The environmental impacts were assessed using the life cycle assessment (LCA) methodology, focusing on the climate change impact category. The economic impacts were calculated using the levelized cost of electricity (LCOE) and the levelized cost of heat (LCOH). Both assessments considered a cradle-to-grave perspective in three scenarios (SC). SCI considered only electricity generation, while SCII involved the combined production of electricity and heat. These scenarios were compared to conventional CSP and PV technologies (SCIII) and benchmark values from the literature.The LCA results showed SCII was the most preferable: the impacts on climate change were reduced by up to 83% for electricity production and up to 97% for heat production compared to benchmark values. In SCII, the LCOE and the LCOH in the CSP+ plant were lower than the average benchmark values, with reductions of up to 70% for electricity and 40% for heat. The sensitivity analysis showed that the environmental performance was strongly influenced by the operating lifetime. For economic performance, the weighted cost of capital was the most influential factor.

Enhancement of fuel cell based energy sustainability for cell on wheels mobile base stations used in disaster areas

In disaster areas, Cells on Wheels (COW) mobile infrastructures are one of the most widely used solutions to restore communications lost due to power grid collapse or physical damage. The biggest problem with such systems is the low operating time and the inability to ensure energy continuity due to logistical problems.In this proposed study, the solution to the stated problem is focused on, and the use of hydrogen, which is the most important energy option of the future, is proposed as an innovative approach. The PV-hydrogen/fuel cell hybrid energy generation and storage system ensures the continuity of energy required for COW. In this study, the system is analyzed under realistic conditions using radiation and temperature data from different seasons in the disaster area. The energy needed in the proposed system is provided by PV and fuel cell with a control strategy. In addition, the electrolyser in the system contributes to the continuity of the energy by producing hydrogen with the excess energy provided by the PV. COW mobile infrastructures, which have a working time of 3 h under normal conditions, have been provided with energy continuity throughout the day thanks to the proposed system. As a result, this study has revealed that it is a solution to an important problem, especially in disaster areas where information flow is very critical.

Power Scavenging Microsystem for Smart Contact Lenses.

On-the-eye microsystems such as smart contacts for vision correction, health monitoring, drug delivery, and displaying information represent a new emerging class of low-profile (≤ 1mm) wireless microsystems that conform to the curvature of the eyeball surface. The implementation of suitable low-profile power sources for eye-based microsystems on curved substrates is a major technical challenge addressed in this paper. The fabrication and characterization of a hybrid energy generation unit composed of a flexible silicon solar cell and eye-blinking activated Mg-O2 metal-air harvester capable of sustainably supplying electrical power to smart ocular devices are reported. The encapsulated photovoltaic device provides a DC output with a power density of 42.4 µW cm-2 and 2.5mW cm-2 under indoor and outdoor lighting conditions, respectively. The eye-blinking activated Mg-air harvester delivers pulsed power output with a maximum power density of 1.3mW cm-2. A power management circuit with an integrated 11 mF supercapacitor is used to convert the harvesters' pulsed voltages to DC, boost up the voltages, and continuously deliver ≈150 µW at a stable 3.3V DC output. Uniquely, in contrast to wireless power transfer, the power pack continuously generates electric power and does not require any type of external accessories for operation.

Simultaneous solar steam and electricity generation from biochar based photothermal membranes

Clean water and energy are essential for reducing poverty, fostering economic growth and sustainable development while mitigating CO2 emissions. Considering that, solar-powered interfacial vapor or steam generation is sustainable and promising environmental technology for both water purification and energy generation while being CO2-free. Despite continuous research progress, most of the solar absorbers to capture sunlight following heat conversion for steam generation are generally made from expensive nanostructures, which in part prevents their widespread manufacturing for useful applications. Herein, we experimentally demonstrate a biomass-derived carbon composite membrane that nearly covers the entire sunlight spectrum as a solar absorber with an estimated absorptivity of 90%. As a result, the light absorbed yields a surface temperature of 55 °C at the surface of the B700 and 33 °C for water. Evaporation rates up to 1.26 and 1.16 kg/(m2 h) and solar-to-vapor efficiencies of 80 and 74% were recorded in presence of sodium chloride with two different types of biochar B700 and B300 based photothermal membranes, respectively, under 1 sun illumination. The water evaporation in presence of mixed sodium chloride/magnesium chloride reached up to 1.21 and 1.05 kg/(m2 h) with 77 and 69% efficiency with B700 and B300; due to different solar absorber geometry. Furthermore, by merging the thermoelectric technology, we exploit the concept of hybrid clean water and energy generation. At a relative humidity of 60%, the thermoelectric device may generate approximately 0.9 W/m2 power density. These results highlight the interactive effects of biochar and polyvinylidene fluoride with porous hierarchies and enhanced absorption of sunlight, thus enabling a considerable elevation of temperature with great potential for clean water and energy. Overall biochar photothermal membrane represents a significant advancement as low-cost sustainable technology, addressing both water and energy challenges by providing efficient, environmentally friendly solution for freshwater production and clean power generation.

Feasibility analysis of hybrid energy generation systems for desert highway service areas: a case study in northern Xinjiang, China

Highways consume a significant amount of electrical energy annually, especially in remote desert regions where the cost of electricity is high. This research explores the utilization of natural resources along desert highways to establish hybrid energy generation systems for service areas. Three service areas along the desert highway in northern Xinjiang, China, serve as case studies. To assess the feasibility of hybrid energy generation systems in these service areas, meteorological data for the three locations were obtained from the NASA platform. The HOMER Pro software was employed for technical, economic, and environmental analyses of the systems. The results indicate the feasibility of Photovoltaic (PV)/Wind/Battery hybrid energy systems in the Huanghuagou, Kelameili, and Wujiaqu service areas. The application of these hybrid energy generation systems across the three service areas could provide 3,349,557 kWh of electrical energy annually for the desert highway. Sensitivity analysis reveals that the Net Present Cost (NPC) and Cost of Energy (COE) values decrease with increasing radiation levels, while NPC shows an increasing trend with growing load demand, and COE exhibits a decreasing trend. Among the three regions, Wujiaqu demonstrates the highest economic viability, with a COE of $0.34/kWh and an NPC of $3,141,641/kWh. Furthermore, Wujiaqu exhibits the lowest environmental impact, with CO2 emissions of 198,387 kg/yr, SO2 emissions of 493 kg/yr, and NOx emissions of 1,711 kg/yr.

Empirical Model for electrical power demand in Mexico

In recent decades, the average global temperature has risen rapidly, due to the modern society activities. Hence, the United Nations has suggested that an increase of 1.5°C above the reference temperature corresponding to the beginning of industrial revolution era must be avoided. One proposal to mitigate this global warming is the migration towards green energy generation systems, however, suitable predictions of electricity demand are required to properly manage the implementation and operation of hybrid energy generation systems with high penetration of renewable energies. In this paper, a simple mathematical model based on sinusoidal functions which consider the normal time periods of the society like daily, weekly, monthly, and annual is proposed for the electricity demand in Mexico. The model parameters were obtained from the historical data from 2017 to 2021, furthermore, the model was used to estimate the electricity demand for the year 2022 as a demonstration of its usefulness, obtaining a mean absolute error of 0.9% in the whole year period. The proposed model is simple and can be used to reproduce and estimate the electricity demand of the national interconnected system.

Sizing and Simulation of a Photovoltaic Hybrid Energy System and Generator for the Electricity Supply of the Residence of the Governor of Mamou, Guinea

Sizing and Simulation of a Photovoltaic Hybrid Energy System and Generator for the Electricity Supply of the Residence of the Governor of Mamou, Guinea

Reinforcement learning robust nonlinear control of a microgrid with hybrid energy storage systems

The parameter variations in the microgrid models including internal and external faults, modelling uncertainties, unexpected changes in load or disturbances and harmonic currents are unavoidable in a microgrid. Here, a hybrid energy generation system consisting of Proton-Exchange Membrane Fuel Cells)PEMFC(/PhotoVoltiaic)PV (/Battery Energy Storage System)BESS(is considered. A new Backstepping Fractional order Adaptive Terminal Sliding Mode Control (BFATSMC) based on Reinforcement Learning (RL) is designed to soar robustness and disturbance rejection for an autonomous microgrid. To verify the performance of the BFATSMC a comparative study is investigated and the proposed method is applied to an islanded microgrid. In the presence of nonlinear and unbalanced loads with harmonic, unmodeled dynamics, and parametric uncertainties, the proposed method has successfully controlled the voltage.

Emended snake optimizer to solve multiobjective hybrid energy generation schedulin G

This paper proposes an emended snake optimizer (ESO) for solving hydrothermal, pumped hydro, and solar generators? non-convex, highly constrained, and non-linear power generation scheduling problem. The generation scheduling problem aims to reduce thermal generator operating costs and pollutants by maximizing hydro volume and utilizing solar power generation. The minimization of operating costs and pollutants is subjected to various constraints, like meeting load demand, active power generation violations, water volume utilization, etc. The conflicting objectives of the multiobjective generation scheduling are handled using the non-interactive approach exploiting the price-penalty method. The direct heuristics search is utilized to satisfy the load demand and water volume constraints. The snake optimization algorithm (SOA) often gets stuck in the local minima while solving complex engineering optimization problems, resulting in sluggish convergence behavior. The basic SOA is emended through simple search and opposition-based learning, enhancing exploitation, convergence behavior, and procuring near to global solutions. The simulation studies involve solving unconstrained standard benchmark problems and electric power system problems. The proposed emended snake optimizer offers significant cost savings for electric power systems ranging from 10-15%. Statistical analysis using Wilcoxon signed-rank test and Friedman?s test justifies the amendment. The rapid convergence behavior and Whisker box plots justify the proposed ESO?s robustness.

Techno-Economic-Eco Design and Investigation of Hybrid Energy Generation Systems in Tropics

Techno-Economic-Eco Design and Investigation of Hybrid Energy Generation Systems in Tropics

Hybrid Energy Generation System with Brushless Generators

Important technical and financial hurdles exist when attempting to extend the power system to remote areas. Decentralized power generation utilising renewable energy sources (RES) has been promoted and is being further investigated as a result. This project showcases a microgrid architecture that uses brushless generators and a single voltage source converter (VSC). Wind and solar photovoltaic arrays are two of the renewable energy sources that power the microgrid system. But to keep the system reliable, there is also a battery energy storage system (BESS) and a diesel generator set. The simplified control and decreased number of switching devices are two benefits of the suggested architecture. In the current architecture, DG is configured as an AC source. The DC connection of the VSC is connected to the wind generator and the solar PV array, both of which are DC sources. Additionally, the BESS is utilised at the DC connection to assist with the dynamic instantaneous power balancing. In addition to integrating systems, VSCs may reduce power quality issues including harmonic currents, imbalance loads, and regulate voltage. To showcase all the aspects of the proposed system, we offer a diverse range of matlab/simulink simulation results.

Resource endowments effects on thermal-economic efficiency of ORC-based hybrid solar-geothermal system

Implementing a high-efficiency hybrid energy generation system requires to comprehensively analyze the influences of multiple factors on the overall performance, including system layout, design parameters, energy resource endowments. For this purpose, this study developed a thermal-economic model for a 300 kW ORC-based hybrid solar-geothermal power generation system at four sites in China, which represents different solar and geothermal energy resources. The optimal configurations of the hybrid system have been obtained for the minimal levelized cost of energy (LCOE) under a certain annual electricity generation (E). The results show that the solar resources continue to play a dominant role in the proposed hybrid system, especially in optimizing the configuration of the system design parameters for the minimum LCOE. Comparing to the individual solar system, the hybrid power generation system significantly enhances its thermal-economic efficiency across the four selected sites, with a maximum increase of 25.34% in E and a maximum decrease of 16.28% in LCOE. Especially in regions with abundant shallow hydrothermal geothermal reservoirs but average solar resources, utilizing shallow geothermal water to preheat Organic Rankine Cycle (ORC) working fluids is a relatively simple yet efficient application of geothermal energy for power generation, worthy of further promotion and implementation.

Energy management strategies of hybrid renewable energy systems: A review

Burning fossil fuels results in more emissions than generating electricity from renewable sources. The transition to renewable energy from fossil fuels, which currently produce the majority of emissions, is essential to preventing the climatic disaster. Hybrid energy generation systems are still in their infancy. It is envisaged that future technology developments would lead to greater application and more economical goods. There will be more standardised designs, which will make it easier to select a system that is suitable for a certain application. The components will communicate more with one another. As a result, control, monitoring, and diagnosis will be made simpler. The hybrid energy system (HES), also known as hybrid power, is expected to be the long-term power solution for microgrid (MG) systems. This study compares and contrasts several theories and conventional approaches to controlling HRES’s control and energy consumption. A successful energy management strategy has been created using a variety of methods and procedures. The effectiveness of an EMS is determined by its control architecture and the solution approach used; common topologies include hierarchical, decentralised and centralised EMS. Supply side management and demand side management, two EMS components, will be discussed later. The three EMS control architectures are examined in this section. In order to determine the most practical and dependable solution with the lowest Net present cost (NPC), COE and realistic environmental consequences, various hybridisation cases of a PV panel, wind turbine, battery storage and diesel generator are designed, analysed and compared using DSM. The results of taking into account DSM indicated a reduction in CO2 emissions of 25%, NPC emissions of 14.8%, COE emissions of 14% and an increase in RF emissions of 8.5%. Two fundamental metrics – the DSM Quality Index for technical benefits and the DSM Appreciation Index for economic advantages – are used to assess the technical and economic benefits of DSM.

Design and Development of Optimal and Deep-Learning-Based Demand Response Technologies for Residential Hybrid Renewable Energy Management System

The principal goal of this study is to conduct a techno-economic analysis of hybrid energy generation designs for residential-form houses in urban areas. Various possibilities for a form house electrification system are created and simulated in order to determine an optimum ideal configuration for meeting residential load demand with an increase in energy capacity and minimal investment. Using NREL’s HOMER optimization tool, a case-study-based virtual HRE model is developed. Pre-assessment data and relevant operation constraints are used to build the system’s objective functions. The instantaneous energy balance algorithm technique is used to solve the multi-objective function. The overall optimization procedure is sandwiched between two supporting advanced approaches, pre- and post-operations. The development of an optimal techno-economic hybrid energy generation system for the smooth fulfillment of urban load demand is aided by novel deep belief network (NDBN)-based pre-stage load demand predictions and an analysis of the necessary demand side management (DSM)practicing code for utility efficiency improvements in post-stage simulations.

Adaptive robust scheduling of a hydro/photovoltaic/pumped-storage hybrid system in day-ahead electricity and hydrogen markets

A hybrid energy generation system (HEGS) exploits the synergies of various energy to improve the utilization rate of renewable energy while enhancing economic efficiency. In deregulated energy markets, this study proposes a scheduling model for HEGS trading in both day-ahead electricity and hydrogen markets to maximize total profits based on price arbitrage. This HEGS is based on a real case in Southwest China and comprises three hydro units, two photovoltaic (PV) plants a pumped-storage facility, and an electrolyzer. The uncertainty of available PV power generation is modelled using polyhedral uncertainty set and then the proposed model is cast as an adaptive robust optimization (ARO) model in which the conservativeness can be controlled by the PV uncertainty budget (ΓPV). Then the column-and-constraint generation algorithm is employed to solve this model. The numerical results reveal that the total profit of HEGS trading in two markets can be increased compared to the case of only trading in the electricity market. For instance, the increase in the total profit is 1.01 % (i.e. 5091 CNY) when ΓPV = 2. Besides, the total profit is considerably affected by ΓPV. As ΓPV increases from 2 to 8 (i.e. the robustness increases), the total profit decreases from 507,045.5 CNY to 503,036.1 CNY. Moreover, sensitivity analysis of the total profit related to the pumped-storage capacity and hydrogen price are also presented.