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[Display omitted] Over the last few decades, great deals on ground-source heat pumps (GSHPs) have been broadly addressed. Various systems of GSHP have been employed worldwide for residential and nonresidential buildings due to their attractive advantages of high energy and environmental performance. The present paper aims to review comprehensively the previous investigations concerning the recent technologies of GSHPs. A brief description of GSHPs and their types, such as open and closed loops and vertical and horizontal GSHPs, is presented. The effects of the employed working fluids and the backfill material on the thermal performance of GSHPs are discussed. Various simulation models that describe the boreholes, such as Kelvin's line-source model, the cylindrical-source model, the finite-length line-source method, Eskilson's model, etc., are discussed. Simulation models utilized in the boreholes as one- and two-dimensional, or quasi-three-dimensional, are studied. The thermal resistance in the borehole, considering the properties of grouting materials and the configuration of borehole flow channels, is evaluated. In addition, different applications of GSHPs integrated with solar systems, cooling towers, ice storage systems, and air-conditioning systems are presented. Finally, the sustainable developments, challenges, and future work of GSHPs are introduced. [ABSTRACT FROM AUTHOR]

An experimental investigation is performed to study the effect of the inclination angle of air jets on heat transfer from a horizontal surface. A pair of inclined circular jets issuing from the straight pipes of length to diameter ratio of 40 is considered. The inclination angles of 0°, 10°, 20°, 30° 45°, and 60° are selected while the Reynolds number is varied from 10,000 to 40,000 based on a jet exit diameter. Jets to impingement plate distance (L/D) as well as the spacing distance (S/D) are changed from 2 to 8. The results of the temperature contours as well as the Nusselt number contours are illustrated to study the characteristics of heat transfer from a flat surface cooled by a pair of oblique jets. The experimental results show that the maximum magnitude of average heat transfer coefficient is achieved in the range of inclination angle from 10° to 20°. Empirical correlations are presented to predict the value of average Nusselt number as a function of Re , Pr , and θ. Moreover, a comparison between the values of average Nusslet number of the present study and those available in the literature is carried out. [ABSTRACT FROM AUTHOR]

In this study, experimental investigation has been conducted on fluid flow and heat transfer of rough mini-channels with rectangular cross sections. The mini-channel considered consists of twelve identical rectangular channels with 4 mm width, 8 mm height, and 80 mm length. Air is employed as the working fluid with Reynolds number varied from 1500 to 5000. Four mini-channels were examined with different values of relative surface roughness ( ɛ ) 1.6 ∗ 10 −4 , 3.45 ∗ 10 −4 , 6.15 ∗ 10 −4 , and 10.5 ∗ 10 −4 . The friction factor ( f ), average Nusselt number ( Nu ), pressure drop penalty factor ( E f ), heat transfer enhancement factor ( E hn ), and universal evaluation parameter (PEC) were evaluated to study fluid flow and heat transfer of rough mini-channels with rectangular cross sections. The results showed that increasing the Reynolds number ( Re ) of air passing through the rectangular rough mini-channel, increases the average Nusselt number ( Nu ) and the pressure drop penalty factor ( E f ), while decreasing the friction factor ( f ) and the heat transfer enhancement factor ( E hn ) which, has a great effect on the universal evaluation parameter (PEC) rather than the pressure drop penalty factor ( E f ). Moreover, a correlation of the relative surface roughness ( ε ) and the universal evaluation parameter (PEC) was obtained. [ABSTRACT FROM AUTHOR]

Experimental study and sensitivity analysis on the heat transfer and pressure drop of a shell and helically coiled tube heat exchanger (SHCTHE) are carried out. The inclination angle ( ɵ ) is varied from the horizontal direction (0°) to vertical direction (90°) by a step of 10° and the coil Dean number ( De c ) is varied from 1540 to 3860. The results indicate that the effectiveness of SHCTHE ( ε ) at the vertical direction is higher than that of the horizontal direction by 26.3% and 23.1% at De c of 1540 and 3860, respectively. Maintaining the SHCTHE in the vertical direction reduces the coil pressure drop comparing with that of the horizontal one by 11% and 32.7% for De c of 3800 and 1800, respectively. Changing the direction of SHCTHE from the horizontal to vertical direction enhances the performance evaluation criteria ( PEC ) by 15.1% and 19.1% for De c of 3800 and 1800, respectively. The ANOVA statistical analysis shows that the effects of the independent variables such as the coil Dean number and the inclination angle of SHCTHE are significant on both the thermal performance and pressure drop. In addition, using multiple regression analysis, correlations are presented to evaluate Nu c and ΔP c as functions of D e c a n d θ with standard deviations of ±2% and ±6.6%, respectively. • The performance of shell and helically coiled tube heat exchanger was investigated. • Effect of the direction of SHCTHE on its performance was assessed. • Changing θ from 0° to 90° improved the Nu c by 12% for De c of 1800. • The sensitivity analysis was achieved using the Analysis of Variance. • Using regression analysis, new correlations were proposed to compute Nu c and ΔP c. [ABSTRACT FROM AUTHOR]

The efficiency, availability, and reliability of thermal management for various engineering applications present a crucial challenge facing the designers and engineers. The rapid development and sophisticated technological advancement require innovative devices possessing high operating capacities that are launched into the prodigious growing markets in all engineering sectors. As a result of pronounced advancements, the jet impingement required to transfer high heat fluxes with a target surface becomes one of the essential priorities for researchers. The intensification of jet impingement can be achieved with different techniques such as passive self-exciting jets, active exciting jets, and hybrid exciting jets. The active methods of self-exciting jets include annular, swirling, and sweeping jets, while the active ones contain pulsed and synthetic jets. In the current study, the heat transfer characteristics and the fluid flow behavior of jet impingement with recent modifications of jets are reviewed comprehensively. As well, the critical methods of passive and active exciting jets considering the jet geometrical and operating parameters are introduced. Moreover, the physical phenomena for each technique in comparison to the conventional circular straight jet as well as the published empirical correlations as available, are studied. The present work reviews the published numerical and experimental investigations considering the different modified jets and its application with various installation geometries that provide a higher efficiency with the augmentation of heat transfer rate. The jet excitation causes topological metamorphosis of flow and hence has a remarkable effect on the intensification of heat transfer. • The intensification of jet impingement can be achieved with different techniques. • Active, passive, and hybrid methods of jet excitation were reviewed. • Heat transfer and fluid flow characteristics of each exciting jet were studied. • The geometrical and operating parameters of each exciting jet were introduced. • Jet excitation increased turbulence intensity and hence intensified heat transfer. [ABSTRACT FROM AUTHOR]

• Fluid flow and thermal performances of PHE are investigated experimentally. • The effectiveness and NTU of PHE are improved with increasing Rr. • Pressure drop and pumping power are increased by increasing Rr. • SHR is improved with increasing surface roughness particularly at low Reynolds number. • Empirical correlations are proposed to predict SHR as a function of Rr and Re. In the present paper, an experimental study of the effectiveness and pumping power of plate heat exchanger (PHE) with rough surface was performed. The experiments were developed for different values of relative roughness, Rr, of 2.6 * 10−4 (smooth surface), 3.4 * 10−4, 7.5 * 10−4 and 9.8 * 10−4 for Reynolds number, Re, varied from 500 to 5000. The average heat transfer rate, Q avg , hence the effectiveness of PHE, ε , and number of transfer units, NTU , as well as pressure drop, Δp , consequently pumping power, P, and specfic heat rate, SHR, were estimated. The results show that Q avg and NTU are enhanced with increasing Rr ; while, they are decreased with increasing Re. At Re = 5000, the effectiveness of PHE with relative roughness of 3.4 * 10−4, 7.5 * 10−4 and 9.8 * 10−4 is greater than that of the smooth surface by 11.5%, 16.6% and 18.6%, respectively. Furthermore, Δp and P are increased by increasing Rr and Re. Moreover, at Re = 500, SHR is enhanced with increasing Rr and its improvements compared with the smooth surface are 39.5%, 23.4% and 6.9% for Rr of 3.4 * 10−4, 7.5 * 10−4 and 9.8 * 10−4, respectively. In addition, empirical correlations are proposed to estimate SHR as a function of Rr and Re with a standard deviation of 5.1%. [ABSTRACT FROM AUTHOR]

This work discusses the novel application of proton exchange membrane fuel cells (PEMFC) in the transport sector as well as portable applications. This kind of fuel cell produces a considerable quantity of heat while in operation. This quantity of heat is about 45–60% of entire energy composition of the hydrogen that is introduced into the cell. A correctly built cooling system must be used to efficiently eliminate produced heat from the stack to extend the stack's life and preserve its efficiency throughout its entire lifespan. Using appropriate thermal management techniques coupled with exploiting possibilities for fuel cell heat recovery may significantly improve size, cost, etc., while also reducing its total energy consumption. It is possible to collect and utilise the heat produced by PEMFC in other applications. A thorough analysis of heat recovery possibilities in this type of fuel cells is presented in this investigation. Similarly, the study further touched on the need for experimental studies into waste heat recovery from proton exchange membrane fuel cells as most of the recent work being championed are modelling based and does not really present a real life scenario of the system investigated. The need for investigations into the environmental performance of the waste heat recovery unit coupled to the proton exchange fuel cell system is also another important research direction that must be considered in future studies. Finally most of the studies on waste heat recovery from fuel cells have largely employed the use of organic Rankine cycle but other types of thermodynamic cycles like Kalina cycle is however recommended for further investigations due to their range of operation hence making them suitable for low and high temperature proton exchange membrane fuel cells. • Role of PEMFC in the transport sector as well as portable applications was discussed. • PEM Fuel cell in Combine Heat and Power Applications was illustrated. • Waste heat recovery in FCs was summarised. [ABSTRACT FROM AUTHOR]

In the current study, the exergoeconomic analysis of a cogeneration pulp and paper plant under bi-operating modes at different environment temperatures of 290, 295, 305, 310, and 320 K was investigated. Two operating modes of the cogeneration system, i.e., a hybrid operating mode using a power boiler and a recovery boiler and a singular operating mode using a power boiler only, were considered. Natural gas was utilized as the main fuel in the power boiler, while black liquor with heavy fuel oil was employed in the recovery boiler. The total capital investment, total operating, exergy, unit exergy, and exergy destruction costs for each operating mode were evaluated. The results indicated that the total capital investment cost was 3420.27 $/h, and the total capital investment and the operation and maintenance costs in the hybrid and singular modes were 5853.27 and 6226.67 $/h, respectively. As well, the unit exergy cost and the exergy cost of steam introduced by the power boiler were 39.31 $/MWh and 2503.69 $/h, respectively. Where these values for the recovery boiler were 34.69 $/MWh and 554.30 $/h, respectively. Furthermore, the exergy destruction costs at an environment temperature of 320 K for the power and recovery boilers were 1436.6 and 213.63 $/h, respectively. In the hybrid mode, the soda at a 10% concentration was recovered, with a rate of 32 t per hour desired for the cooking process in the pulp mill. In addition, the use of black liquor as a bio-fuel in the recovery boiler saved 14% of the consumption of natural gas. • Exergoeconomic analysis was performed for the pulp and paper industry. • Hybrid and singular operating modes for different ambient temperatures were studied. • Unit exergy cost, exergy cost, and exergy destruction cost were evaluated. • Using black liquor as a bio-fuel in RB saved about 14% of natural gas consumption. [ABSTRACT FROM AUTHOR]

In the present study, a thermodynamic analysis of a cogeneration system in a pulp and paper industry under different operating modes i.e., singular and hybrid with a variable ambient temperature is conducted according to actual operating data. For singular operating mode, the power boiler is only employed using natural gas while for hybrid operating mode, the power boiler with the recovery boiler is employed using natural gas and black liquor as main fuels, respectively. The results show that for hybrid operating mode in comparison with the singular one, the thermal efficiency of turbine and condenser is enhanced by 1.36 and 7.7%, respectively while it is reduced by 2.8% for the power boiler. In addition, the overall thermal efficiency under singular and hybrid operating modes is 87.4 and 53.7%, respectively. For hybrid operating mode, the exergy destruction of power boiler decreases by almost 10% compared with that for the singular operating mode. Also, at hybrid operating mode, the soda is recovered with a mass flow rate of 33 tons/hour that is required for the cooking process in the chemical pulp section and additionally the consumption of natural gas in the power boiler is reduced by 11.8%. [ABSTRACT FROM AUTHOR]

The three-fluid heat exchanger is a multi-stream heat exchanger that provides three streams at different temperatures for certain usage objectives. Recently, optimizing heat exchangers generally and three-fluid heat exchangers especially have received great attention in the energy field. The current study objective is to get the optimal mass flow rate of the three streams to minimize the entropy generation number and maximize effectiveness. Optimization is performed on the inserted coiled tube type for 24 cases with different usage objectives and different mass flow rate constraints. The optimization is done using an analytical approach for the temperature profiles and a regressed model for the overall heat transfer coefficients. Single-objective and multi-objective genetic algorithms are the optimization algorithms. The result shows that cooling the hot fluid is the most efficient usage objective; however, heating the intermediate-temperature fluid is the less efficient usage objective. Also, the study shows that the entropy generation number is dependent on the mass flow rate constraint. The maximum effectiveness of 0.693 occurs when the usage objective is cooling the hot fluid. In this case, the mass flow rate of the cold and the intermediate-temperature fluids are maxima while the mass flow rate of the hot fluid is minimum. The minimum entropy generation number 0.0486 occurs when the mass flow rate of the cold fluid is maximum while the mass flow rate of the hot fluid and intermediate-temperature fluid are minimal. [Display omitted] • Heat transfer of a three-fluid heat exchanger is investigated. • A model for optimizing the inserted coiled tube three-fluid heat exchanger is developed. • The maximum errors for the regression models of heat transfer coefficients are 1.72% and 2.81%. • The maximum effectiveness reached about 0.69323. [ABSTRACT FROM AUTHOR]

• Three designs of photovoltaic-based skylights are proposed to save energy in buildings. • The integration of vacuum glazing with photovoltaic skylights is evaluated. • Using a vacuum layer at the backside of the PV layer is favorable for thermal insulation. • Using a vacuum-based PV skylight reduces the total U-value from 6.3 to 1.9 W/m2.K at ASTM. • Using the vacuum layer with the PV-skylight slightly decreases the power generation of the PV. In commercial buildings with large glazing facades, transparent facades and skylights play a considerable impact on energy consumption. In this study, three different photovoltaic (PV) -based skylights are compared to save energy in these buildings. The first skylight uses a vacuum glazing sample as a substrate at the backside of the PV layers. The second design integrates a vacuum glazing layer in front of the PV layers. And lastly, the PV layers are attached to a single layer of glazing with a solar cells covers 25% of the whole area. A 3D thermal model is developed and validated with data from the literature to compare these designs. it is concluded that using a vacuum layer at the backside of the PV layer is favorable for thermal insulation and attains relatively similar power generation to the case without a vacuum layer. In more detail, replacing the single glazing PV skylight with the first skylight design reduces the total U-value of the glazing from 6.3 to 1.9 W/m2.K for a glazing sample with an area of 0.4 m by 0.4 m at ASTM boundary conditions. Furthermore, at received solar irradiance of 1000 W/m2, an ambient temperature of 25 °C, and a wind speed of 1 m/s, replacing the third skylight design with the first skylight design slightly reduced the electricity generation from 37.4 W/m2 to 36.4 W/m2, significantly decreased the heat flux transfer from 91.1 W/m2 to 50.5 W/m2 and lowers the indoor surface temperature from 32.1 °C to 27.1 °C. [ABSTRACT FROM AUTHOR]

Sustainable energy storage medium has increased significantly in recent times. Air contamination, which is widely considered to be harmful to an ecological niche, has fuelled the growth of sustainable energy sources. On the other hand, adopting sustainable energy technology can create significant issues for keeping the grid stable. With variations in the output of renewable energy sources, storage is essential for power and voltage balancing. Storage of electricity is necessary for energy management, frequency control, peak shaving, load balancing, periodic storage, and backup production in the event of a power outage. As a result, storage technologies have received increasing attention and have evolved into something more than a need in today's world. This article provides a thorough assessment of battery energy storage systems. In addition to describing the features and capabilities of each type of battery storage technology, it also discusses the benefits and drawbacks of each innovation when contrasted to other storage mediums. There are comparative charts with many features of each storage technique provided and descriptions of the various uses of energy storage methods. Furthermore, The current work discussed the batteries' strengths, weaknesses, opportunities, and threats (SWOT) analysis in power transmission. • Current state of Battery Energy storage system technology is discussed. • Comparative study on types of battery energy storage is evaluated. • SWOT analysis of notable types of battery is presented. [ABSTRACT FROM AUTHOR]

Carbon capture (CC), along with the efforts to reduce carbon emissions at the source, is a major action toward the mitigation of climate change and global warming due to emissions of greenhouse gases (GHGs). Carbon emissions amount to 36.3 Gt-CO 2 in 2021 from 31.5 Gt-CO 2 in 2022, with a drop of about 1.5 Gt-CO 2 in 2020 relative to 2019 due to the COVID-19 pandemic. The carbon emissions originate from heat and power, transportation, process industries, and residential activities constitute 47.7, 24.9, 18.9, and 8.5% of the total emissions, respectively. The process industries represent the second large-scale point-source of carbon emissions next to heat and power. Additionally, the process industries have high-intensity carbon emissions up to 0.6–0.8 t-CO 2 /t-cement, 1.4–2 t-CO 2 /t-steel, and 2.7–99.2 kg CO 2 /bbl, with flue gas streams having high CO 2 concentration up to 30%. In comparison to 0.4 t-CO 2 /MWh and 3–16% CO 2 in the flue gas from heat and power facilities, these process industries present a highly effective target for CC application. This work reviews and critically discusses the large-scale application of CC to different process industries, namely, cement, iron and steel, oil refinery, and chemicals. CC can be achieved by three main approaches, i.e., post-combustion, pre-combustion, and oxyfuel combustion. Post-combustion and chemical-looping are the common CC approaches utilized in process industries, with the first being widely applied due to its ease of incorporation, and the latter is commonly used in the cement industry. CC with the capacity in the range of 0.4–2 Mt-CO 2 /yr is planned for cement plants relative to current capacities of 75 kt-CO 2 /yr. Similarly, CC capacity up to 0.8 Mt-CO 2 /yr has been integrated into iron and steel plants, in which captured CO 2 is utilized for enhanced oil recovery (EOR) applications. In the oil and gas industry, CC has been widely utilized, in the context of gas purification, being an essential gas processing unit, with CC capacities up to 1.4 Mt-CO 2 /yr, and plans to reach 4 Mt-CO 2 /yr. CC cost is the main challenge for the widespread implementation of CC in process industries with a wide range of reported costs of USD9.8-250/t-CO 2 depending on the process industry and the CC technology used. [Display omitted] • Process industries emit about 18.5% of the global carbon emissions. • Cement, iron & steel, and oil refining are the major CO 2 emitting processes. • Carbon capture (CC) is a major mitigation action of climate change. • The current process industry's CC capacity of 7 Mt-CO 2 /y has to increase to the Gt-CO 2 /y scale. • CC cost and integrability to existence processes present the main challenges. [ABSTRACT FROM AUTHOR]

The rapid progress in the global population and technical advances have resulted in exponential growth in the use of fossil fuels. These are not only limited in resources but also have a severe environmental impact. The accumulation of greenhouse gases (GHGs), more specifically carbon emissions, in the environment has resulted in severe health issues and climate changes. The Paris Climate Agreement calls for restricting global warming to only 1.5 °C by 2050 relative to the pre-industrial era. This requires reducing global GHGs emissions as soon and as much as possible. Massive efforts are being put into minimizing GHG emissions, such as using renewable energy resources and/or using carbon capture technologies (CCT). In this study, different CCTs were introduced, focusing on the pre-combustion as a promising CCT approach. In this work, the role of CCT in realizing the United Nations Sustainable Development Goals (SDGs) was thoroughly analyzed and discussed. A total of 87 indicators were developed to measure and analyze the contribution of CCT to achieving the different SDGs. The focus given to the role of the pre-combustion CCT in achieving SDGs is being elaborated. The indicators and analysis covered the economic, environmental, and social pillars of sustainable development. It was found that CCT contributes well to all 17 SDGs, with core and substantial contributions to SDG-7 of "Affordable and clean energy", and ultimately SDG-13 of "Climate action". The developed indicators would work as a guideline for the different players to ensure that CCT is fully adhering the SDGs principles. The proposed indicators have nine main benefits, i.e., assist in the achievement of the SDGs, providing information for the decision-makers, enhance and benchmark sustainability performance, improve risk management, enhance data management and reporting practices, improve resource allocation and reduce the expenses, improve environmental performance, reduce social impact, and improve communications with stakeholder. Moreover, the different barriers facing the CCT were presented. • The role of the CCTs in achieving sustainable development and SDGs were presented. • Develops a set of 87 novel indicators to assess the contribution of CCT into SDGs. • Monitoring and evaluation of these indicators help to maximize CCT contribution to SDGs. • The interrelation between CCT and circular economy with related SDGs were presented. • The barriers facing the CCTs were elaborated and linked with SDGs. [ABSTRACT FROM AUTHOR]