Renewable Energy Fraction Research Articles

Design and performance assessment of a pumped hydro power energy storage connected to a hybrid system of photovoltaics and wind turbines

Worldwide, the overdependence on conventional power plants for electricity generation has been one of the most significant economic and environmental challenges. Renewable energy sources have become the most viable option to overcoming this issue. Recently, a hybrid renewable energy system consisting of wind turbines and photovoltaics combined with a pumped hydroelectric energy storage system has received considerable interest. However, neglecting crucial parameters, such as head losses and evaporation rate, might reduce the accuracy of the total simulation performance, resulting in an underestimation of the correct size of each component. This study investigates this issue by proposing a robust approach with a strategy to establish the ideal pipe design through an in-depth techno-economic assessment. A comparative analysis between two different scenarios in which one considers head loss and the other does not is carried out. A wide range of proposed system configurations has been thoroughly investigated. The essential performance indicators employed for designing the proposed system are the renewable energy fraction and the loss of renewable energy, and the results reveal that these two indicators have improved by approximately 8.6% and 3%, respectively. The most significant annual variation between the two scenarios regarding the total demand satisfied by the proposed system and the amount of renewable energy loss is 218.23 GWh and 89.39 GWh, respectively. The pipe efficiency at the pumping and generating modes, which is determined through a sensitivity analysis, ranges between 91-99% and 76–95%, respectively. These findings could assist designers in making initial assumptions about such parameters with reasonable confidence.

Optimum Design of an Electric Vehicle Charging Station Using a Renewable Power Generation System in South Korea

In the context of global warming and fossil fuel depletion, electric vehicles (EVs) have become increasingly popular for reducing both carbon emissions and fossil fuel consumption. However, as the demand for EV charging power rises along with the expansion of EVs, conventional power plants require more fuel, and carbon emissions increase. This suggests that the goal of promoting EV adoption to mitigate climate change and reduce reliance on fossil fuels may face significant challenges. Therefore, there is a need to adopt renewable energy generation for EV charging stations to maximize the effectiveness of EV distribution in an eco-friendly way. This paper aims to propose an optimal renewable energy generation system for an EV charging station, with a specific focus on the use of an actual load profile for the station, the consideration of carbon emissions and economic evaluation, and the study of a specific case location in Korea. As a case study, an EV charging station in Korea was selected, and its renewable energy fractions (REF) of 0%, 25%, 50%, 75%, and 100% were considered for comparison of carbon emissions and economic evaluation with the help of HOMER software. In addition, the system with 25% REF was analyzed to find the best operating strategy considering the climate characteristics of the case site. The results show that the system configuration of PV/ESS is the most economical among all the REF cases, including PV, WT, and ESS, due to the meteorological characteristics of the site, and that the system with REF below 25% is the most optimal in economic terms and carbon emissions.

Grid-connected hybrid renewable energy systems for supermarkets with electric vehicle charging platforms: Optimization and sensitivity analyses

Coupling energy and transport sectors is critical for optimum utilization of renewable energy. The present work proposes a grid-connected photovoltaic/wind/battery hybrid power system to generate electricity for supermarkets. The supermarkets are located at three geographically distinct cities in Morocco and integrate electric vehicle (EV) charging stations in their parking areas. HOMER grid software is used for the optimal design of the proposed hybrid renewable energy system (HRES) with an accurate utility tariff corresponding to the Moroccan scenario. Dakhla, which is a high windy site, is found to be the best implementation site with maximum renewable energy fraction (REF), minimum COE and operating costs of 71.66%, 0.0841 $/kWh, and 0.124 M$/year, respectively. The optimal grid-connected system consisted of 107 kW p of PV, 300 kW of wind, 12 batteries, and 65 kW capacity inverter for Dakhla site. The next identified best site is Casablanca while Fez remained at third place based on COE and annual operating costs. At all of these sites, the EV charging process is achieved, almost completely, with 7300 charging sessions annually. A series of sensitivity analyses is performed based on supermarket energy intensity, renewable energy availability, and carbon pricing and impact on the viability of HRES was evidenced.

Techno-economic analysis of green hydrogen as an energy-storage medium for commercial buildings

Abstract Green-hydrogen production is vital in mitigating carbon emissions and is being adopted globally. In its transition to a more diverse energy mix with a bigger share for renewable energy, United Arab Emirates (UAE) has committed to investing billions of dollars in the production of green hydrogen. This study presents the results of the techno-economic assessment of a green-hydrogen-based commercial-building microgrid design in the UAE. The microgrid has been designed based on the building load demand, green-hydrogen production potential utilizing solar photovoltaic (PV) energy and discrete stack reversible fuel cell electricity generation during non-PV hours. Given the current market conditions and the hot humid climate of the UAE, a performance analysis is derived to evaluate the technical and economic feasibility of this microgrid. The study aims at maximizing both the building microgrid’s independence from the main grid and its renewable fraction. Simulation results indicate that the designed system is capable of meeting three-quarters of its load demand independently from the main grid and is supported by a 78% renewable-energy fraction. The economic analysis demonstrates a 3.117-$/kg levelized cost of hydrogen production and a 0.248-$/kWh levelized cost for storing hydrogen as electricity. Additionally, the levelized cost of system energy was found to be less than the current utility costs in the UAE. Sensitivity analysis shows the significant impact of the capital cost and discount rate on the levelized cost of hydrogen generation and storage.

A Study of Integrated Model for Electricity Supply Chain Considering Renewable Energy Fraction and Demand Variation

This paper aims to derive integrated model for electricity supply chain considering renewable energy fraction and demand variation. Currently, attention is being paid to increasing the ratio of renewable energy generation in the electric power market which called Green Energy Coefficient (GEC). This paper aims to derive an integrated model of electricity supply chain considering renewable energy fraction and demand variation using multi-agent reinforcement learning. The subjects of the models are the consumption market model, the electricity market model, and the production market model. Also, the pricing process in electricity supply chain is analyzed using the proposed multi-agent simulations.

Sustainable Power Generation Using Archimedean Screw Turbine: Influence of Blade Number on Flow and Performance

Hydropower has been one of the mature renewable energy systems encompassing a major fraction of renewable energy. Archimedean screw turbines are gaining new interest in hydropower generation that are suitable for low head applications. This paper empirically and experimentally studies the flow inside Archimedean screw turbines along with the influence of blade numbers on their performance. The major objective of this work is to investigate performance and conduct design optimization of a screw turbine operating under ultra-low head (<0.2 m) conditions. Experimentally verified empirical results show its reliability in estimating the performance of turbines at low operational speeds. Further, the results show that with the increasing number of blades, the efficiency and power generation capacity can be increased, but the overall performance improvement relative to one blade turbine peaks at around 7 blades. Increasing the power generation capacity can in turn make the turbine compact and could be fabricated at a low-cost.

Feasibility of solar hybrid energy system at a conservation park: Technical, economic, environmental analysis

Access to clean, reliable, affordable energy has become vital for sustainable development. However, such energy facilities are still unavailable in many rural areas worldwide. The implementation of the clean energy system in remote locations is often challenging. This paper aims to design a hybrid energy system for a conservation park and analyze its technical, economic, and environmental performance. A campsite located in Royal Belum State Park, Malaysia, is chosen as a case study. HOMER Pro software is used to assess the feasibility of different system configurations. In terms of net present cost (NPC), the best system configuration is a 4.13 kW PV array, 11 kWh battery bank, and 0.85 kW converter. It is followed by a PV/DG/Battery system with an NPC of 12767.91 USD. A rise in battery capacity, energy generation, and the initial cost are observed with the increase in the share of PV capacity. It was understood that the PV/DG/Battery hybrid system is technically superior to the standalone diesel system in terms of renewable energy fraction and energy storage autonomy. In terms of economic performance, the PV/DG/Battery system fares better than other configurations with the lowest cost of electricity, payback period, and highest return on investment. High carbon avoidance and negligibly small carbon emission are the unique benefits expected from PV/Battery configurations. In this study, PV/Battery is expected to avoid around 3407.39 kgCO2 annually. This study is expected to shed light on designing an effective hybrid energy system at a conservation park.

Evaluation of capacity of hybrid energy systems to decrease the environmental pollution

• As the use of fossil fuels increases, emissions to the environment increase. • The optimum solution for the hybrid system in Karabük includes solar, wind, diesel generator, battery and hydrogen storage. • Cost increases as renewable energy constraint increases. • As the utilization the renewable energy of 50%, the fuel consumption decreases by 28% and 43% in Eskipazar and Karabük, respectively. • Although the system cost increases with the renewable energy utilization, the carbon emission decreases. Renewable energy sources emit less carbon than traditional energy sources, although generally cannot sustain a stable storage system. This research focuses on hybrid energy benefits by modeling in the HOMER PRO software. In this study, hybrid power systems in different renewable energy fractions using Solar, wind, and hydrogen systems in two regions which are Karabük province were investigated in terms of cost, damage to the environment, and system architecture. The most suitable system in terms of net present cost emerged in Eskipazar, the leveled energy cost (LCOE) for this scenario was $0.367. But, in the case of 50% hybrid renewable energy system (GEN/PV/BAT/WT/HYDROGEN STORAGE) utilization in Eskipazar, the LCOE was determined as $0.389. Besides, the lowest fuel consumption was generated as 196,936,731 L per year in the Eskipazar with a 50% renewable energy fraction, whereas the highest was 353,454,007 L/year in Karabük without a renewable energy fraction. As the utilization the renewable energy of 50%, the fuel consumption decreased by 28% and 43% in Eskipazar and Karabük, respectively. Although the system cost increased with the renewable energy utilization, the emission of harmful gases and materials released into the atmosphere decreased.

Optimizing hybrid power system at highest sustainability

Abstract The current research investigated the utilization of fuel cells as an energy storage unit in microgrid energy system applications in an effort to enhance self-consumption of renewable energy. The prototype evaluation is constructed of solar photovoltaic and fuel cell energy storage units. The study utilizes experimental weather and electrical load data for household obtained at 1-min temporal resolution. The daily average energy consumption for the evaluated household was 10.3 kWh, with a peak power output of 5.4 kW and an annual energy consumption of 3757 kWh. The Solar System under investigation has a capacity of 3.6 kWp, while the fuel cell system has a capacity of 0–3 kW, allowing for effective integration with the photovoltaic system and a maximum renewable energy fraction. The research indicates that by installing fuel cells powered by hydrogen generated from renewable energy sources, self-consumption and self-sufficiency significantly increase. The annual energy flow demonstrated that the implementation of 2.5 kW fuel cells improved renewable fraction utilization from 0.622 to 0.918, while increasing energy self-consumption by 98.4% to 3338.2 kWh/year and self-sufficiency by 94.41% to 3218.8 kWh/year.

Hierarchical optimization of policy and design for standalone hybrid power systems considering lifecycle carbon reduction subsidy

To achieve the target of carbon neutrality, the present work proposes a lifecycle carbon reduction subsidy policy to promote the exploitation of renewable energy technologies in remote areas. The hierarchical optimization of policy and design for a standalone hybrid renewable energy system is further conducted based on the proposed subsidy policy. The upper-level policy optimization model aims to maximize the renewable energy fraction and minimize the subsidy expenses borne by the government simultaneously, and the lower-level design optimization model aims to minimize the net present cost borne by the system operator. Four meta-heuristic algorithms coupled with a standard iterative method are employed to solve the hierarchical optimization problem, and their performances are comprehensively assessed in terms of convergence, robustness, and computational efficiency. Besides, an improved K-means clustering algorithm along with a tailored optimal K-value selection strategy is employed for scenario reduction. The results of the case study show that: (ⅰ) teaching-learning-based optimization performs the best convergence and robustness as it achieves the balance of exploration and exploitation. (ⅱ) the nexus between policy and system design presents a piecewise pattern, implying that the system configuration will change significantly only when the subsidy policy exceeds a certain threshold. (ⅲ) the proposed subsidy policy is expected to increase the renewable energy fraction to 99.23% and reduce the lifecycle carbon emissions by 80.7%. Overall, the proposed subsidy policy and its impact mechanism on system design can provide theoretical support for the government to formulate tailored policies for different preferences, and the proposed optimization framework and methodology can be directly extended to practical applications.

Optimization based on movable damped wave algorithm for design of photovoltaic/ wind/ diesel/ biomass/ battery hybrid energy systems

The actual energetic situation has several challenges such as pollution, the rarefaction of fossil fuel and the dangers of nuclear. Renewable sources are proposed as a solution and suggested, such as a cost-effectiveness system. The paper deals with the problem of feeding a domestic load with electricity which should respect the ecologies factors, so this work is a design problem of the hybrid renewable energy systems; PV/biomass, PV/diesel/battery, PV/wind/diesel/battery, and wind/diesel/battery to choose the best one of them which feed the load with the lowest cost. The study’s goal is to design a microgrid system by the minimization of the total investment cost with respect to the required technical factor, the minimum allowed renewable energy fraction, and the minimum allowed availability factor. The methodology flowed utilizes frameworks based on a recent algorithm called Movable damped wave algorithm (MDVP). The proposed optimization algorithm is compared with other algorithms to prove its efficacy which are; the artificial electric field algorithm (AEFA), harris hawks optimization (HHO), and the grey wolf optimizer (GWO). The project case study is investigated in Al-Majmaah, Saudi Arabia. The contribution of this work is implementing a recent algorithm that proves its efficacy and finding the best microgrid configuration following many investigations and comparisons. The results confirm that the MDVP is better compared to the other algorithms, its computational time is fast, and its convergence is good; otherwise, the PV/biomass is considered the best configuration in the area of study with a size of 237.698 m2 from PV panel and 954.097 t/year of biomass, which obtained the best Net Present Cost (NPC) of $299504, and a cost of energy (LCOE) assumed as $0.228/kW. A sensitivity analysis is applied to prove the effect of size variation on project factors. The simple observation, by the way, is that any change in the PV size affects the output factors.

Techno-Economic Feasibility Analysis of a Solar Photovoltaic Hybrid System for Rural Electrification in Sierra Leone for Zero Carbon Emission

Remote area electrification is a crucial need in sub-Saharan Africa’s drive to attain universal electrification. In Sierra Leone, with a rural population of over 5 million, the electrification rate accounts for less than 10% of the total inhabitants. This paper presents a comparative techno-economic analysis carried out to determine the most feasible of four individual options for off-grid mini-grid power generation system utilizing sources that include: Solar Photo Voltaic (SPV), Diesel Generator (DG), and Battery Storage (BS) system, to provide electricity for a rural and remote village located in the northwestern part of Sierra Leone (longitude 9.1°W and latitude 12.6°N), with an average daily solar irradiance between 4.6 and 6 kWh/m2/day. An assessment of the total electrical load estimated an expected daily consumption of 178 kWh. Simulation, optimization, and sensitivity analyses of each one of the individual power generation systems were carried out using HOMER software. Economic parameters such as Cost of Capital (CC), Net Present Cost (NPC), Levelized Cost of Electricity (LCOE)), technical parameters (energy production characteristics), and greenhouse gases emissions were compared and analyzed. Key findings from the simulation result indicate that systems consisting of DG only ($29,750) and SPV/BS ($110,131) obtained the least and highest CC, respectively. Similarly, in a respective manner, the highest and least NPC were obtained for systems with DG only ($496,336) and PV/DG/BS ($152,491) over a 25-year project lifetime. Furthermore, the least LCOE was obtained for the system comprising PV/DG/BS ($0.336/kWh). With an expected annual generation of (75,121 kWh), PV/DG/BS was obtained to be the most optimal solution. The sensitivity analysis observed that a reduction in the discount rate consequently reduces the LCOE of such a system. Furthermore, the model accounts for a 90% renewable energy fraction, with a significant reduction in the amount of annual GHG emissions, when compared with a generation system using diesel generator only.

Feasibility Study and Techno-Economic Analysis of Solar PV-Biomass Hybrid Power System: A Case Study of Kajola Village, Nigeria

Efficient and sustainable electric power supply is needed for effective healthcare delivery, provision of quality education system, and building of impactful social/human infrastructures. Unrestricted access to reliable and affordable electricity will improve people's welfare and enhance quality healthcare delivery globally. The need to reduce the harmful impact of Greenhouse gas emissions along with its fossil fuel emissions have necessitated the need for the numerous research interests in low-carbon power generation systems. The feasibility and techno-economic analysis of an off-grid Solar Photovoltaic (PV)/Biomass (BG)/Diesel (DG)/Battery (BB) hybrid system for a rural village-Kajola, Nigeria was conducted in this paper. Renewable energy sources (RES) parameters such as irradiation data, biomass resources, and DG parameters were collected from National Aeronautics and Space Administration (NASA)’ database, Ekiti State Ministry of Agriculture and manufacturers’ price lists respectively. The load demand assessment of the area was conducted and analyzed through the use of questionnaires. All the relevant data collected were used as input into the HOMER software. The optimal configuration is the PV-BG-BB combination. The Levelized Cost of Energy (COE) is $0.178/ kWh, with renewable energy fraction (RF) of 100%. This means that nearly all of the energy used by the hybrid system to meet the load is generated from renewable sources. The proposed solar PV/Biomass generator/Battery bank hybrid energy system can supply electricity to the village under consideration at an hourly average of approximately 52.7 kW and with an average daily energy need of 483.71 kWh. The study will serve as a template for all electric power system stakeholders and potential investors on the feasibility and optimal design of hybrid renewable energy system for rural electrification.

Performance analysis of autonomous green energy system based on multi and hybrid metaheuristic optimization approaches

The need for energy is constantly increasing worldwide. It is expected that renewable energy resources and fuel cells, solid wastes, and hydrogen energy technologies will play a significant role in energy generation and storage with their decreasing installation costs and increasing environmental concerns. Hydrogen is a potential fuel used in fuel cells that provides a carbon-free solution. The research is based on the techno-economics of off-grid wind (WT), solar (PV), biomass gasifier (BG), and fuel cell (FC) systems, which include storing excess wind and solar energy by converting it to hydrogen to provide fuel cell energy. It is critical from the standpoint of feasibility. In addition to electricity generation, energy storage integration, sizing methodologies, energy flow management, and the optimization algorithms that go with them are all covered. The annual cost system (ACS) is the primary goal function of the optimization process in this case. A robust rule-based energy management scheme is proposed to coordinate the power flow between various system components of a microgrid that will minimize the ACS and meet the energy demand reliably. The decision variables considered for this optimization process are PV panel power, WT power, and number of H2 tanks. The consumption and meteorological data of the year 2021 are used as the input of the system. The optimal size of each component is obtained by using the proposed Hybrid Firefly Genetic Algorithm (HFGA). To prove the superiority of the proposed optimization method in terms of accuracy and calculation time, it is compared to approaches that are used in similar applications such as Genetic Algorithms, the Firefly Algorithm, Sine-Cosine Algorithm and Cuckoo Search Algorithm. The optimum system configuration yielded 1094.68 KW WT, 2256.17 kW PV, and 775 H2 storage tanks when HFGA was used. The ACS of the system is $2921702.3, the total net present cost is $2.4639x107, while the leveled unit energy cost is $1.3416/kWh 'dir. The renewable energy fraction of the system is 100 % and consists of 51.8 % PV, 2.1 % WT, 11.8 % FC 34.3 % BG components. The results show that the proposed standalone hybrid (PV/WT/BG/FC) energy system is the most cost-effective option for the central campus of the university selected as the study area, and the proposed algorithm has excellent convergence capacity and provides high-quality outputs. The optimization algorithms are programmed using the MATLAB simulation package in this study.

Techno-Economic Analysis of Hybrid Diesel Generators and Renewable Energy for a Remote Island in the Indian Ocean Using HOMER Pro

This study is about the electrification of the remote islands in the Indian Ocean that were severely affected by the tsunami in the 2004 earth earthquake. To supply electricity to the islands, two diesel generators with capacities of 110 kW and 60 kW were installed in 2019. The feasibility of using renewable energy to supplement or replace the units in these two generators is investigated in this work. In 2019, two diesel generators with capacities of 110 kW and 60 kW were installed in the islands to supply electricity. This work analyses whether the viability of using renewable energy can be used to supplement or replace these two generators. Among the renewable energy options proposed here are a 100 kW wind turbine, solar PV, a converter, and batteries. As a result, the study’s goal is to perform a techno-economic analysis and optimise the proposed hybrid diesel and renewable energy system for a remote island in the Indian Ocean. The Hybrid Optimisation Model for Electric Renewable (HOMER) Pro software was used for all simulations and optimisation for this analysis. The calculation is based on the current diesel price of USD 0.90 per litre (without subsidy). The study found that renewable alone can contribute to 29.2% of renewable energy fractions based on the most optimised systems. The Net Present Cost (NPC) decreased from USD 1.65 million to USD 1.39 million, and the levelised Cost of Energy (CoE) decreased from 0.292 USD/kWh to 0.246 USD/kWh, respectively. The optimised system’s Internal Rate of Return (IRR) is 14% and Return on Investment (ROI) 10%, with a simple payback period of 6.7 years. This study shows that it would be technically feasible to introduce renewable energy on a remote island in Indonesia, where numerous islands have no access to electricity.

Exploring energy storage methods for grid-connected clean power plants in case of repetitive outages

Inadequate access and unstable grid service are among the most severe difficulties developing communities face. As a result, these communities depend on fossil fuel-based technology to supply their electrical demands, which has significant socioeconomic consequences for society. The objective of this paper was to investigate greener, more sustainable technologies, such as solar battery storage systems. This research proposed a sizing technique for grid-connected photovoltaic systems with different battery technologies through techno-economic feasibility analysis. In the suggested method, the techno-economic performance of photovoltaic energy systems with five different battery technologies was compared: lead-acid battery, lithium-ion battery, vanadium redox battery, and nickel-iron battery. For different grid outage frequencies, this investigation was conducted (0 to 500 interruptions per year. The key comparison indices considered are the investment cost, renewable energy fraction, and surplus electricity. The grid-connected photovoltaic/nickel-iron battery system was shown to be the most efficient at high main grid failure frequencies.

Techno-Economic Feasibility Analysis of Solar PV- Wind Grid-connected Hybrid Energy systems for Electrification in Sultanate of Oman

Sultanate of Oman’s power sector is undergoing a rapid restructuring to involve renewable energy sources as part of the generation system. The present power sector majorly depends on the a-renewable energy source, natural gas for its power generation. CeA central grid system connecting all the provinces of Oman involving renewable and non-renewable energy sources in power generation is initiated and is gaining acceleration. Hybridization and its optimization of energy resources at different locations based on geographical factors, cost of electricity production, greenhouse gas emission, and initial and operating costs involved in the generation is still a major concern for the development of a central grid system. In this paper, the development of an optimal hybrid system for the load profile of the University of Technology and Applied Sciences – Shinas (UTAS- Shinas) is done. The initial study was done to develop load profile data of UTAS- Shinas. The annual Peak demand of the University is 720 kW. Various hybrid and standalone combinations involving renewable and non-renewable options are simulated and analysed with a hybridization software tool, HOMER Pro. Solar PV and wind are the major renewable energy resources, found to have ambient potential in Oman. When a renewable energy system is there in the hybrid system design, a non-renewable energy source can be added as a backup generation system to improve its system reliability. Optimization of the hybrid combinations is required as the cost of electricity generation will be expensive, if a wrong combination is selected. Out of the different hybrid combinations selected, PV- Wind – Natural gas-based hybrid system was found to be the most beneficial system for UTAS- Shinas, after considering Renewable energy fraction of 61.6 % power, which can penetrate to the system, the Net Present Cost (NPC), Cost of Energy (COE), Payback period and Greenhouse gas (GHG) emission control as the constraints for the optimization procedure. The practical implementation is done on campus by taking a sample load and illustrating the project with power sources PV of 3.5kW, wind energy conversion of 1.5kW, and grid connection from Majan Electricity Company with an auto change over the facility.

Conversion of greenhouse gases to synthetic fuel using a sustainable cyclic plasma process

In the present article, a new thermodynamic process is proposed in which a thermal plasma reactor is utilised to dissociate carbon dioxide/steam blend into synthetic fuel using chemical looping technology. Chrome/chrome oxide (Cr/Cr2O3) pair was used as the oxygen carrier and also the thermal transport medium between the thermal plasma reactor and a synthetic fuel fluidized bed reactor. The proposed process was hybridised with renewable energy resources including solar photovoltaic and wind to account for the energy demand of the thermal plasma reactor. Results showed that at a molar ratio of CO2/Cr = 1.12 and steam/Cr ratio = 2.8, the syngas quality referred to as H2: CO > 2.05, which is suitable for liquid fuel production and Fischer-Tropsch applications. Also, the thermal plasma reactor reached chemical conversion >0.99 at 5273 K, while SFR represented the conversion extent >0.95 at 1473 K. The highest thermodynamic efficiency of the proposed process was 0.43 with a 3 MW electricity production capacity that could be utilised by thermal plasma aiming at improving self-sustaining factor of the system. The integration of the system with solar photovoltaic and wind in Whyalla, South Australia, showed that the renewable energy penetration in the proposed system can be as high as 68.4% with battery storage of 30 MWh together with an installed capacity of 50 MW and 37.5 MW for photovoltaic panels and wind turbines, respectively. Larger battery storage did not affect the renewable energy fraction as solar irradiance and wind velocity were not sufficient to complete the charging cycle of the battery.

An Adaptable Net Zero Model: Energy Analysis of a Monitored Case Study

Increased efforts toward climate change mitigation and achieving net zero (NZ) are occurring globally. This research addresses three challenges to meeting the target NZ goals: (1) quantifying energy use reduction approaches, including energy efficiency and renewable power; (2) obtaining measured data to verify NZ achievements; and (3) providing NZ definitions to a globally understandable concept. To do so, a reorganized NZ concept (NZX%(ORG)) is proposed that is practical, measurable, and adaptable to different regions and requirements. The “X%” presents the fraction of renewable energy to the total energy used, and the “ORG” defines the organization’s NZ definition that a project uses. The objective of this proposal is to create a universally NZ concept and method, using measured utility power data, by (1) determining a baseline NZX%(ORG); (2) projecting an optimized NZX%(ORG); (3) measuring and reporting the actual NZX%(ORG). This application is extendable from a building level to the community, city, and country levels (NZCX%(ORG)). The Serenbe community, a monitored case study in Georgia, was analyzed. The baseline NZ rating using metered data was NZC16%(ASHRAE). The analysis showed that improved energy efficiency measures (lighting, windows glazing, air sealing) along with increased on-site solar power generation (from 10% to 25% of all roof space), provided a projected NZC80%(ASHRAE). In addition, publicly available documentation of the measured utility power is required for reporting the actual NZCX%(ORG) in Serenbe. Using NZX%(ORG) provides recognition of partial success in moving toward 100% renewable power.

Hybrid energy storage design and dispatch strategy evaluation with sensitivity analysis:Techno‐economic‐environmentalassessment

AbstractInternational Energy Agency reported the net‐zero carbon target by 2050 in its recent annual report. The global energy landscape is expected to anticipate an energy transition with an increase in renewable energy share from 12% to 35% for electricity sector by 2050. Most of the countries in the world had pledged to be become net‐zero or carbon neutral countries by 2050. Solar photovoltaic (PV) and wind energy will contribute 50% of energy mix in this context. Solar PV and wind energy are intermittent resources that highly depending on the weather and climate conditions. The intermittency issues caused mismatch between electricity generation and demand profiles. This will greatly affect the requirement of meeting the daily load profile, satisfying the peak demand and resulting in generation of surplus, and so on. Energy storages play a vital role in this scenario by allowing this excess energy to be stored and used to meet the demand during low energy production. Previous literature evaluated the feasibility of utilizing battery energy storage in large‐scale solar PV plant in Malaysia using load following dispatch strategy, which can be further enhanced by utilizing a hybrid energy storage system. This study aims to develop an optimized hybrid energy storage system utilizing battery and supercapacitors to complement a large‐scale solar PV system. This study also evaluates two dispatch strategies that are load following and cycle charging for three different power system configurations. Subsequently, a market leading battery is modelled with parameters such as nominal voltage, capacity, round‐trip efficiency, minimum and maximum state of charge, and maximum and minimum charge and discharge current in four different scenarios utilizing two dispatch strategies. These studies are conducted using power system and energy storage modelling tools with localized energy data for the Malaysia context. The proposed hybrid energy storage system demonstrates an improvement of about 30% in annual throughput under the load following dispatch strategy. The hybrid power system also increases the renewable energy fraction by 5% in the system. This study creates an optimized framework in the development of energy storage for grid integration that permits high level of solar PV penetration in the transmission and distribution network.