With this correction, the Editorial Office, together with the authors, is making the following amendments to the published article [1]: (1)In Figure 1b, the diagram shows isentropic processes from state 1 to state 3, but a note indicating that this was done for simplicity and that the actual processes are non-isentropic was accidentally omitted [...]

Without a doubt, many remote areas have a hidden potential of energy, which can be considered for electricity production. Indeed, energy supply for remote areas is one of the most critical targets of SDGs BY the 2030 year. Based on this explanation, this paper presents a techno-economic analysis of hybrid energy systems installable for two capital provinces of Iran, concerning SDGs targets. Firstly, a comprehensive investigation of SDGs and UN-Habitat III targets are described and then, concerning these targets and existing data gathered by the meteorological organization of Iran, a techno-economic analysis is conducted using Homer software. Regarding the high potential of renewable energies in Zahedan and Zanjan cities of Iran, implementing hybrid energy systems could be feasible for producing electrical energy as a correct policy and a good vision by policymakers and energy experts in the future. In this respect, a PV-Wind-Generator system is investigated in this paper for producing electricity in the two mentioned cities. Technical analysis of the solar energy for Zahedan is showing that the total amount of electricity production by the hybrid system is about 40,617 kWh/yr. In addition, the total amount of electricity production by this hybrid system for Zanjan is to equal 41,728 kWh/yr. Therefore, regarding this high potential of energy in these areas, investment on the solar energy for both cities has economic justification, while from the wind energy potential viewpoint, only Zahedan is proper for investment.

In this paper, a multigeneration cycle of electricity, cooling, and Bitcoin whose energy source is geothermal, has been subjected to energy, exergy, and economic analyses. The cycle under consideration includes the steam cycle (upstream cycle), the carbon dioxide cycle (downstream cycle), and the liquid–gas line to absorb the heat dissipated by the carbon dioxide cycle. In this cycle, the steam cycle condenser acts as the carbon dioxide cycle evaporator. Part of the electricity generated by this cycle is used to generate Bitcoins. Energy and exergy efficiencies at baseline (excluding Bitcoin production) are 45.8% and 38.1%, respectively. In this cycle, if more power is spent on producing Bitcoin as a product, the energy and exergy efficiencies of the cycle are reduced. Because Bitcoin itself is not valuable in terms of energy and exergy. Considering the average price of Bitcoin during the years 2015–2022 and if 100% of the electricity generated by the system is spent on Bitcoin production, the payback period in 2018, 2021, and 2022 when the price of Bitcoin is equal to $13,412.4, $21,398.8, and $47,743.0, respectively, are less than the baseline. Therefore, the production of Bitcoin with a variety of renewable energies can be considered as a solution. Of course, it should be noted that large changes in the price of Bitcoin can affect the issue of economic benefit.

The continuous increase in population is causing a lot of pressure on energy production sector due to the huge demand at domestic and industrial scales. Developed and developing countries have set restrictions on the energy use from greenhouse gas emissions point of view. Hydrogen as a clean source of energy has been given full research consideration due to its high energy density. However, there are many challenges in producing hydrogen efficiently, economically and environmental friendly. Hydrogen can be produced from biomass and water splitting processes using renewable energy sources, which are extensively discussed in this work. The strength, weakness, opportunities and threats (SWOT) of hydrogen production processes are presented and discussed considering different methods of hydrogen production. Moreover, energy, exergy, economic and environment analyses (4E) for hydrogen production from water splitting process are discussed. In addition to SWOT factor, political, economic, social and technological (PEST) considerations are also considered.

There are different methods for hydrogen production, among which thermo-chemical cycles are particularly important. One of the most common thermochemical cycles is the copper-chlorine cycle. In this cycle, the water electrolysis process takes place during a thermo-chemical reaction, and copper chlorine is used as a thermochemical reaction intermediate. This cycle requires two factors to produce hydrogen: A heat source with a temperature of about 520 oC and electricity. For this reason, it is possible to use the hot waste gases of industries or parabolic through collector and heliostat field to provide its heat. To supply electricity for this cycle, various alternatives from the power grid and wind turbine to heat recovery in cycles that use low-temperature energy sources are considered. In this article, the integration of the copper-chlorine cycle with power generation systems has been discussed and investigated from the perspective of energy, exergy, and economics. This review is divided into two general parts using renewable and non-renewable resources. At the beginning of this article, various methods of hydrogen production focusing on the copper-chlorine cycle have been briefly discussed. In the following, the way this cycle works is explained along with energy, exergy, and economic equations, and the research done in this direction is explained. Finally, a strategy for how to integrate the copper-chlorine cycle with other systems is described. Studying this article, in addition to giving a better attitude in the field of integrating this cycle with other plants, is similar to a guideline for using the cycle along with other systems for better productivity. The conducted investigations showed that the recovery of hot industrial exhaust gas as a source of heat for the Cu-Cl cycle has a high potential for saving energy consumption and reducing environmental pollutants. To produce the required electricity, it is recommended to use cycles that work with a low-temperature energy source, such as the organic Rankine cycle and Kalina cycles. Also, if renewable energy sources are used, it is recommended to use parabolic through collectors and heliostats to produce the required heat. As in the case of non-renewable energy sources, cycles with low-temperature energy sources can be used.

The present study aims to minimize the overall heat transfer coefficient (U-value) and heat flux through building walls to improve indoor thermal comfort, using different bricks and insulating materials in building wall construction. The building walls of three different types of bricks (Type-1, Type-2, and Type-3) were tested to compare the U-value through the wall. The brick with the low U-value was used to build a composite wall with the addition of glass wool and air cavity. The experiment was conducted maintaining different hot chamber temperatures (40 degrees C to 65 degrees C) to see the effect of hot chamber temperature on the U-value. The temperature of the cold fluid chamber is increased by 0.9 degrees C in 0 to 210 min of testing duration. The maximum heat flux using Type3 brick in the composite wall is reduced by 3.37%, and the percentage reduction in indoor temperature is 40.83%. Steady-state numerical analysis was also performed to perceive the temperature distribution on the composite wall surface and found to be well-matched with the experimental model with a percentage deviation of 1.96%. The results suggested that using glass wool and air cavities with low thermal conductivity, low density, and high specific heat capacity effectively reduces the U-value throughout the building wall.

AbstractThis study investigates the viability of hybrid photovoltaic (PV), wind, and fuel cell (FC) systems for on‐grid and off‐grid operations for the Ashrayan‐3 housing project in Bangladesh, with an increased focus on sustainable energy solutions. Motivated by the issue of the delivery of proper and sustainable energy services to remote locations, we conducted an extensive analysis of load demand and found that an average daily demand of 46,176.65 kWh exists, with a peak load of 4852.8 kW. In this research, the HOMER software has been used to make a simulation of five different hybrid system configurations with differing mixes of renewable technologies. From the analyses, the systems based 100% on renewable resources suffer more initial capital costs, with a total net present cost increase of up to 20%, in comparison to conventional systems. On the other hand, the systems give much lower operational costs and cost of energies (COEs) of a minimum of $0.0253/kWh, reported from the on‐grid PV‐based system. On the other hand, the off‐grid PV–FC–wind turbine system showed a COE of $0.286/kWh, along with a decrease in CO2 emissions by about 15,000 kg/year, showing a 30% decrease, compared with on‐grid systems. The results form a basis for the conclusion that such hybrid renewable energy systems are both economically and environmentally feasible. They can reduce COEs by up to 70% in off‐grid systems. This proves that the quality of life and energy security in developing regions will be highly increased, supporting the goals of sustainable development.

The increase in the feasibility of hydrogen-based generation makes it a promising addition to the realm of renewable energies that are being employed to address the issue of electric vehicle charging. This paper presents technical and an economical approach to evaluate a newer off-grid hybrid PV-hydrogen energy-based recharging station in the city of Jamshoro, Pakistan to meet the everyday charging needs of plug-in electric vehicles. The concept is designed and simulated by employing HOMER software. Hybrid PV-hydrogen and PV-hydrogenbattery are the two different scenarios that are carried out and compared based on their both technical as well as financial standpoints. The simulation results are evident that the hybrid PV- hydrogen-battery energy system has much more financial and economic benefits as compared with the PV-hydrogen energy system. Moreover, it is also seen that costs of energy from earlier from hybrid PV-hydrogen-battery is more appealing i.e. 0.358 $/kWh, from 0.412 $/kWh cost of energy from hybrid PV-hydrogen. The power produced by the hybrid PV- hydrogen - battery energy for the daily load demand of 1700 kWh /day, consists of two powers produced independently by the PV and fuel cells of 87.4 % and 12.6 %, respectively.

Photovoltaic (PV) technology can be categorized as a mature technology but its performance with its elevating temperature has a negative effect and opens a new area of research which led to the introduction of photovoltaic thermal collector (PVTC) systems. PVTC systems integrate PV modules and solar thermal collectors in a single unit to derive energies from uninterruptible solar sources. This review article is limited to the design and development of the heat exchangers used in typical air and water-based PVTC system. Heat exchangers are used to improve the heat transfer from the back surface of the PV module, thereby improving its overall efficiency. The review shows that for air-based PVTC, the electrical efficiency with various types of heat exchangers lies in the range of 4-24%, whereas for water-based PVTC is 5.1-15.8%. The maximum thermal efficiency achieved for the water-based system is observed to be 72% against the 87% for the air-based system indicating that a significant approach has been made in the air-based system with the novel concept of the heat exchangers as compared to the water-based system. At the end of the paper, some future recommendations are also commented on to make the PVTC system more viable.

Abstract The current study presents research investigations and developments related to the homogeneous charge compression ignition (HCCI) engine. Research investigations and recent advances, including the role of various operating conditions on HCCI engine combustion phenomena, emissions, and performance, are discussed. There is growing research interest in investigating HCCI engines with diesel fuel to study combustion, emissions, and performance characteristics due to their association with low NOx emissions. In the published literature, research investigations are also conducted with different fuels ranging from biomass to diesel to gasoline in the HCCI engine showing its capability for utilizing various fuels in coming years. The challenges associated with HCCI combustion are reviewed, and the details of excessive carbon monoxide and unburnt hydrocarbon emissions are discussed. The major parameters affecting the hydrogen addition in HCCI diesel engines are also discussed. Overall, adding hydrogen to a diesel‐fueled HCCI engine improves combustion phasing and can potentially increase thermal efficiency while lowering emissions. In addition, the strength, weaknesses, opportunities, and threat analysis is provided and discussed thoroughly.

Water scarcity threatens human life and it is likely to be a main concern in the next century. In this work, a novel multigeneration system (MGS) is introduced and assessed with energy, exergy, and economic analyses. This MGS includes a gas cycle, multieffect distillation, an absorption refrigeration cycle, a heat recovery steam generator, and electrodialysis. Electrodialysis is integrated into this configuration to produce sodium hydroxide and hydrogen chloride from brine to prevent its release to the environment with harmful impacts. The other products are electricity, cooling, and demineralized water. For the evaluation of the proposed system, one computer code is provided in engineering equation solver software. For physical properties calculation, the library of this software is used. The MGS produces 614.7 GWh of electrical energy, 87.44 GWh of cooling, 12.47 million m(3) of demineralized water, and 0.092 and 0.084 billion kg of sodium hydroxide and hydrogen chloride over a year. Energy and exergy evaluations demonstrate that the MGS energy and exergy efficiencies are 31.3% and 18.7%, respectively. The highest and lowest value of exergy destruction rate is associated with the combustion chamber and pump, respectively. The economic evaluation indicates that the net present value of this proposed system is 3.8 billion US$, while the internal rate of return and payback period, respectively, are 0.49 and 2.1 years.

Aiming to net-zero emissions, hybrid power generation through renewable means has gained substantial attention across the globe. Considering the stochastic nature of renewable energy resources, a comprehensive performance assessment is a must prior to project development. Present work is a novel multidimensional 6E analysis (energy, exergy, economic, environmental, advanced exergy, and exergoeconomic) to evaluate the performance of hybrid wind-solar energy systems. The analysis is performed using long-tern (41 years) high-resolution ERA5 reanalysis resource data and the mathematical modeling by means of MATLAB R2018a computation software. The long-term data facilitates reliable and precise predictions of resource availability, power generation, and system performance during the lifespan of the project. The performance of HWSES in terms of capacity factor and exergy efficiency is computed to be 9.6–35.5% and 4.7–10.4% respectively, whereas the extended exergy efficiency lies in the range of 3.39–5.79%. Hybridizing wind power projects with solar power enhances the overall system capacity factor, exergy efficiency, and extended exergy efficiency by 3.46%, 5.12%, and 2.87% respectively. Hence, the hybridization leads to superior year-round system performance with smaller power fluctuations than the standalone systems. Further, wind, solar and hybrid systems would annually reduce the Specific Emission Reduction of 1128 tone/kW, 1685 tone/kW, and 1407tone/kW respectively. The present research will be helpful to the policy-makers and the project developers in the project feasibility study of hybrid energy systems.

High-energy demand with rapid industrialization and mechanization combined with environmental pollution due to the burning of fossil fuels has driven a shift toward renewable energy. Biogas derived from biomass is a potential renewable energy source that can be used in different sectors such as transportation sector, electricity generation, heat production, combined heat and power (CHP) systems, and fuel cells. Moreover, the upgraded biogas can be applied as transportation fuel via an internal combustion chamber (for internal combustion engine (ICE) vehicles), and electricity station (for electric vehicles). In the present work, a conceptual review of biogas-based electrical power production systems is presented. It is clear that the conventional types of biomass contain a high amount of pollutants and unwanted constituents, which lower the lower heating value (LHV) of biogas fuel. Moreover, the energy and exergy efficiencies of biogas applications are influenced by these components. Consequently, several biogas-upgrading technologies have been elaborated to increase the LHV of biogas fuel by removing biogas pollutants. So, the energy and exergy analyses of biogas-driven plants are discussed in this regard. Also, the economic analysis of biogas-fueled systems is measured through the connection between biogas production, purchased electrical power, and selling of an additional amount of biogas. Biogas represents an important source of renewable energy as shown before, and it helps in waste management and W-to-E (waste to energy) conversion, which allows utilizing huge amounts of wastes instead of disposal or landfill procedures. However, handling of biogas from production to utilization has an impact on the environment. Therefore, the assessment of the environmental impacts of biogas plants is presented. In addition, a combination of the biogas energy with other sources, especially renewable energy sources (eg, solar-biogas, geothermal-biogas, wind-biogas, CHP, CCHP, and concentrated photovoltaic-biogas), and reusing waste energy for other tasks (eg, employing the waste heat from a gas turbine) are examined.

Because non-renewable is energy resource depletion and environmental pollution, researchers and governmental policymakers considered two options: (1) replacing the non-renewable energy resource with renewable ones and (2) improving the performance of non-renewable fueled systems by considering techniques such as combined heat and power by recovering the energy of exhaust hot gas for heating utilization. In this paper, the integration of biomass-fueled micro-gas turbine (MGT) with superheated Kalina cycle was evaluated by the energy, exergy, economic and exergoenvironmental (4E) analyses. The products of this system are electrical energy produced by the superheated Kalina cycle (SKC) and MGT, as well as heating energy recovered from the gasifier. Also, other biomass types are examined and the performance of the system is investigated by using them. From the energy and exergy point of view, integration of the SKC to MGT biomass-fueled improves the system energy and exergy efficiency from 30.7% and 26.1% to 51.7% and 50.8%, respectively. In this system, the highest and lowest percentage of exergy destruction rate is related to the SKC and gasifier. The economic analysis shows this integration is beneficial and it reduces the system payback period (PP) from 9.07 to 4.6 years. The parametric study shows that increasing the air content in the gasifier improves the system performance while increasing the water content decreases it.

In this study, a novel multigeneration system is considered from energy, exergy, and economic points of view. The combined system composed of biomass gasifier, CO2 cycle, cooling system, multi-effect distillation (MED), and electrodialysis was assessed. This integrated system produces electricity, cooling, distilled water, sodium hydroxide (NaOH), and hydrogen chloride (HCl). A parametric study regarding moisture content of biomass, the efficiency of expander I, LHV of biomass, the salt concentration of seawater, and a number of MED effects on system performance was conducted. The obtained energy and exergy efficiencies of modeled MGS are 75.1% and 88.4%. The highest and lowest exergy destruction rates (EDR) belong to the liquefied natural gas line and electrodialysis, respectively. The proposed MGS produces 73.17 GWh of cooling, 103 GWh of electrical energy, 1223 Ton of NaOH, 1114 Ton of HCl, and 212.6 m3 of potable water annually. The influence of expander I on energy and exergy efficiencies of the CO2 cycle was investigated. Results revealed that increasing the LHV of the biomass results in a decrement of both energy and exergy efficiencies of MGS and recovery ratio. When considering the biomass moisture content, the efficiencies of exergy and exergy of MGS diminished with a rise in moisture amount.

Energy, exergy, economic, exergoenvironmental, and environmental analyses are reported for a novel polygeneration system consisting of a geothermal cycle, a CO2 cycle, a reverse osmosis unit, an electrodialysis unit, a lithium bromide absorption chiller, and a liquefaction unit for natural gas. The proposed system is able to produce electricity, cooling, desalinated water, sodium hydroxide, and hydrogen. To study the environmental aspects of the proposed facility, the associated social cost of air pollution is determined. This parameter implies a comparison between nonrenewable and renewable energy systems to produce the same amount of electricity, while the amount of air pollutants generated and their associated costs are considered. Three scenarios are introduced. The results indicate that the system produces 631 GWh/year electrical energy, 465 GWh/year cooling, 6.22 left-to-right markton/year NaClO, 1.57 x 10(8) m(3)/year hydrogen, and 386,000 m(3)/year potable water for a geothermal working fluid supplied with mass flow rate of 100 kg/s at a temperature of 150 degrees C and a pressure of 457.5 kPa. Also, the calculated values of the energy and exergy efficiencies are 58.3% and 94.2%, respectively. The payback period is determined to be 5.3 years. The net present value left-to-right markis found to be left-to-right mark113.6 million US$ which is lower than that for all the nonrenewable-based scenarios considered.

The emission of greenhouse gases from fossil fuels is the main environmental impact of energy resources. Moving toward the use of renewable energy resources is the only solution to tackle these problems. In this paper, a configuration of the hybrid biomass and geothermal energy resource is examined for cooling and electricity generation. In this study, water as a geothermal working fluid is heated up due to combustion of syngas produced in a digester and produce power in a steam turbine. So, the remaining heat of this geofluid runs an absorption chiller for cooling production. The results reveal that the energy and exergy efficiencies of this proposed cycle are 30.8% and 15.5%, respectively. Moreover, the economic analysis of this cycle concludes that the payback period is 2.8 years and the simple payback period for this configuration is 2.6 years. Moreover, the highest exergy destruction rate of 52.4% belongs to the absorption refrigeration cycle. Whereas the lowest exergy destruction of the steam line is the lowest value of 17.4%.

In this chapter a brief summary about on- and offshore wind turbines is presented. Energy and exergy analyses of wind turbines are presented, for which a numerical example of a wind turbine located in Tehran, Iran is demonstrated. The results show that the energy and exergy efficiency may reach 35.7% in May and 13.5% in December, respectively.

This paper investigated optimization of two objectives function include the total amount of heat transfer between two mediums and the total cost of shell and tube heat exchanger. The study was carried out for k-type heat exchanger of the cryogenic unit of gas condensates by multiple objective particle swarm optimization. Six decision variables including pipe pitch ratio, pipe diameter, pipe number, pipe length, baffle cut ratio, and baffle distance ratio were taking into account to conduct this simulation-based research. The results of mathematical modeling confirmed the actual results (data collected from the evaporator unit of the Tehran refinery's absorption chiller). The optimization results revealed that the two objective functions of heat transfer rate and the total cost were in contradiction with each other. The results of the sensitivity analysis showed that with change in the pitch ratio from 1.25 to 2, the amount of heat transfer was reduced from 420 to 390 kW about 7.8%. Moreover, these variations caused reduction in cost function from 24,500 to 23,500 $, less than 1%. On the other hand, an increase in pipe length from 3 to 12 meters, the heat transfer rate raised from 365 to 415 kW by 13.7%, while the cost increased from 20,000$ to 24500$ about 22%.