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• Three parallel compressors more efficient than two variable speed compressors. • R452B versus R410A led to better efficiencies and compatibility at high ambient. • Reliable oil return of three parallel compressors having multiple capacity levels. • Three parallel centrifugal blowers led to improved air flow distribution. This study delineates a meticulous exploration of technologies to enhance the energy efficiency of rooftop air conditioning units, employing the DOE/ORNL heat pump design model for comprehensive engineering design and optimization. A baseline rooftop air conditioning unit, featuring a 13 ton (45.7 kW) cooling capacity and a 17.9 integrated energy efficiency ratio, served as the point of departure for substantive efficiency enhancements. Key modifications included the consolidation of two refrigerant circuits into one, integrating three parallel 2-stage (dual-speed) compressors, fan replacements with high-efficiency substitutes. Notably, a lower global warming potential refrigerant, R452B, was evaluated as a substitute for R-410A, demonstrating better performance in the lab prototype. The achieved measured integrated energy efficiency ratio of 21.4 in the lab prototype surpassed the baseline integrated energy efficiency ratio. Comparative evaluations between R410A and R452B indicated heightened efficiency with the latter, showcasing a lab-demonstrated integrated energy efficiency ratio of 22.4 at the rated capacity of 13.8 ton (48.5 kW) and 23.9 integrated energy efficiency ratio at the rated capacity of 10 ton (35.2 kW). This research underscores the successful development of a rigorous, energy efficient rooftop air conditioning unit prototype with noteworthy environmental and economic implications. [ABSTRACT FROM AUTHOR]

Passive ultra-low energy buildings represent an effective strategy for energy conservation and emission reduction within the global building industry. The prolonged and cold winters in severely cold regions of China necessitate substantial heating energy consumption. The study utilized a combination of overall surveys and long-term tracking surveys to evaluate the indoor environment and energy consumption in a passive office building situated in severely cold region under different heating modes over 2 years. The results show that the average temperature and indoor air quality (IAQ) can meet the standards at most moments. However, the average relative humidity tends to fall below the specified lower limit. Nevertheless, the Predicted Mean Vote (PMV) index suggests that the indoor environment provides a comfortable thermal experience for humans. The heat pump air conditioning (HPAC) system operation revealed that when the outdoor air temperature fell below −7°C, the coefficient of performance (COP) of the air source heat pump units would deteriorate. Implementing intermittent heating during the second year can reduce heating energy consumption by 13.4 kWh/(m2·a), resulting in 38.9% energy savings. These findings will serve as a valuable reference for the design and operation of heating systems in passive buildings in severely cold regions. [ABSTRACT FROM AUTHOR]

Combining mine exhaust waste heat with existing heat pump technology is a promising technical route to realise the efficient extraction and scientific use of low-grade waste heat resources in mines and to solve the problem of insufficient heat supply in remote mining areas. This study proposes a new type of mine-exhaust-air heat exchange coupled with heat-pump waste-heat-utilisation system based on deep enthalpy heat extraction. Using a mining area in Northwest China as a representative case, this study establishes a systematic exergy analytical model and a thermo-economic model. Through an in-depth analysis of the different evaporation temperatures and condensing temperatures, the system's energy efficiency ratio (COP) reaches its optimal performance, with the total exergy efficiency surpassing 90%. The minimum efficiency of the subsystem return air heat exchanger is 35%. The unit thermal costs of the mine exhaust air waste heat utilisation system and a conventional coal-fired boiler system are 0.1291 and 0.1573 million RMB/kW·h, respectively. This is a thermal economics cost saving of 21%. The studied system demonstrates great economic viability and the potential for energy saving throughout its life cycle. [ABSTRACT FROM AUTHOR]

Carbon capture and storage can reduce the carbon emission directly and effectively. Absorption carbon capture (ACC) is currently the most promising way to remove CO2 from coal-fired power plant, yet the main drawback is the excessive thermal energy consumption for the regeneration process. In this study, a new ACC system that utilizing the low-grade waste heat to generate steam has been proposed, in which system the steam is compressed to increase the saturation temperature to satisfy the thermal energy grade demand of the absorbent regeneration. Heat pump is introduced to increase the inlet pressure and enhance the energy and economic effect of vapor compression and R245fa is found suitable for the system. The vapor generating work can be controlled below 200 kWh t−1 when Twh is higher than 60°C, and COPvg can be higher than 3.5 for situations of Ttag,sat not exceeding 130°C. The energy performance and economic analysis of the proposed ACC system driven by the new vapor generation method is analyzed. Off-peak operation by ASS shows good economic effect, the operating cost for the regeneration process of carbon capture is only 69.70 CNY t−1 CO2 under the worst condition and far below the traditional heating method. The new heat supply method for carbon capture presents reasonable energy and economic performance, which is shown suitable for peak shifting of the power grid. [ABSTRACT FROM AUTHOR]

Aiming at the problem of excessive energy consumption in the thermal regeneration system of a rectisol process in a certain petrochemical engineering company, process improvement is carried out. A closed heat pump distillation model was proposed, using NRTL thermodynamic model with annual total cost and thermodynamic efficiency as objective functions. Process parameters were optimized and their economic and environmental benefits were analyzed under different compression ratios. The research results show that closed heat pump distillation can effectively reduce the use of superheated steam and condensate when the compression ratio is 1.8, and the total energy consumption is reduced by 62.71% . When the investment payback period are 5 years and 8 years, annual total cost is reduced by 15.64% and 32.79%, respectively. The thermodynamic efficiency has been improved from the original 8.78% to 20.96%, which has excellent economic and environ-mental benefits, and the results of the study are expected to provide guidance for the development and design of advanced heat pump distillation technology. [ABSTRACT FROM AUTHOR]

The Hewlett Packard Enterprise–Cray EX Frontier is the world's first and fastest exascale supercomputer, hosted at the Oak Ridge Leadership Computing Facility in Tennessee, United States. Frontier is a significant electricity consumer, drawing 8–30 MW; this massive energy demand produces significant waste heat, requiring extensive cooling measures. Although harnessing this waste heat for campus heating is a sustainability goal at Oak Ridge National Laboratory (ORNL), the 30 °C–38 °C waste heat temperature poses compatibility issues with standard HVAC systems. Heat pump systems, prevalent in residential settings and some industries, can efficiently upgrade low-quality heat to usable energy for buildings. Thus, heat pump technology powered by renewable electricity offers an efficient, cost-effective solution for substantial waste heat recovery. However, a major challenge is the absence of benchmark data on high-performance computing (HPC) heat generation and waste heat profiles. This paper reports power demand and waste heat measurements from an ORNL HPC data centre, aiming to guide future research on optimizing waste heat recovery in large-scale data centres, especially those of HPC calibre. [ABSTRACT FROM AUTHOR]

This study proposes a novel onboard carbon capture system (OCCS) with reduced fuel consumption. The proposed system included a heat pump with an intermediate heat exchanger, a parallel compressor, and a steam compressor. The proposed system consumed 43% less fuel than the boiler for producing the same amount of steam, which was required for CO2 stripping. In addition, a blended solvent of amino methyl propanol (AMP) and piperazine (PZ) was applied to the OCCS. A rate-based process simulation indicated that this solvent resulted in 22% lower reboiler duty, compared to a monoethanolamine (MEA) solvent. Further, it was shown that the proposed OCCS with the heat pump and the AMP/PZ solvent achieved a reduction of approximately 50% in both fuel consumption and CO2 emissions along with 26.9 USD reduction for capturing one ton of CO2, compared to the OCCS with a boiler and MEA solvent. [ABSTRACT FROM AUTHOR]

This paper presents the results of the technical validation of an innovative prototype for drying alfalfa bales. It is based on a 4.1 kW Heat Pump (HP) that uses an advanced technology (optimized for extracting the humidity from the air) and is directly powered by a 6.6 kWp PV generator without grid or batteries support. The main technical challenges of this work were managing solar irradiance fluctuations due to cloud-passing and achieving good drying efficiency. The prototype has been validated for two consecutive drying campaigns in La Rioja (Spain). There were no abrupt stops generated by cloud-passing. The PRPV, which evaluates the performance of the PV system only during the periods when the PV energy can be used by the HP unit, presented values of 0.82 and 0.85, comparable to a well-performing grid-connected PV system. Although the bales' initial relative humidity (RH) ranged from 18 to 30%, all but one of them presented a final RH below 16%, which is the limit point to avoid fermentation. The drying times ranged from 1 to 5 h, and the specific energy consumption per liter of water extracted, from 0.7 to 1.46 kWh/L. These values are comparable to traditional diesel and grid-powered systems. It is worth noting that the agricultural drying market represented USD 1.7 billion in 2023. [ABSTRACT FROM AUTHOR]

This review aims to analyze recent advancements in heat pump dryers (HPDs) with a focus on improving energy efficiency and conservation in drying processes. The objective is to evaluate the components, structures, and refrigerants used in HPDs, examining their environmental impacts and system performance. The methodology includes a comprehensive comparison of various assisted HPD systems, such as infrared-, ultrasound-, and solar-assisted technologies, to assess their experimental benefits and limitations. By using key performance metrics, the paper evaluates the energy efficiencies of HPDs in comparison with traditional drying methods, discussing their applications across different industries. The study also explores the significance of integrating alternative energy sources to enhance the efficiency and economic viability of HPDs. Future research directions are proposed to further develop the technology for commercial use, emphasizing HPDs' potential to provide energy-efficient and high-quality drying solutions. In quantitative terms, the review notes that the coefficient of performance (COP) for HPDs ranges between 3.5 and 4.5, indicating a significant improvement over traditional drying methods. Specific moisture extraction rate (SMER) values for HPDs are reported to be between 0.8 and 1.2 kg kW−1 h−1, demonstrating superior efficiency in moisture removal. Additionally, specific energy consumption (SEC) for HPDs is found to be 0.5–0.7 kW h kg−1 of evaporated moisture, which is substantially lower compared to conventional dryers. These metrics underscore the energy-saving potential and enhanced performance of HPD technology. [ABSTRACT FROM AUTHOR]

The escalating utilisation of second homes has led to an extension in heating periods and, to a certain degree, renovations to elevate the standard, resulting in augmented energy and resource consumption. A comprehensive survey was conducted in Sweden, examining user patterns across different seasons, heating systems, and implemented energy efficiency measures. The results indicate that second homes are occupied for extended periods during the summer season and intermittently throughout the year. Over half of the second homes are heated even when unoccupied, with 12% maintaining a temperature above 16 °C. The predominant heating method is direct electricity (32.2%), followed by heat pumps (29.5%) and stoves (17.5%). A variety of renovations are undertaken, primarily to enhance the standard and technical performance, but also to implement energy efficiency measures such as window replacement, additional insulation, or heat pump installation. Based on the reported user and heating patterns, and the energy renovations carried out, the potential energy savings with different energy renovation strategies were estimated for the Swedish second home stock. The results show that though lowering the temperature when a second home is unoccupied emerges as the most efficient measure, both in terms of cost-effectiveness and climate impact, it needs to be complemented with intermittent heating or dehumidification to ensure that the relative humidity is below critical levels, to avoid the risk of damages caused by, for example, mould growth. Installing a heat pump is the second most energy- and cost-effective measure and has the advantage that the indoor temperature can be maintained at rather high levels. [ABSTRACT FROM AUTHOR]

CO2 refrigeration and heat pump systems have gained widespread attention due to their environmentally friendly features. However, their application is limited by high operating pressure and limited refrigeration performance. To address this, the technology of adding other refrigerants to CO2 to form a CO2-based mixture has emerged as an effective solution, as it reduces operating pressure and improves energy efficiency. Although CO2-based mixtures can be mixed in any ratio, there is an optimal composition ratio that maximizes performance under given working conditions. However, as working conditions change, the optimal composition ratio also changes, and fixed compositions cannot achieve the best energy efficiency throughout the year. Therefore, this paper studies four types of CO2-based mixtures, namely CO2/R32, CO2/R290, CO2/R1270, and CO2/R1234yf， and proposes a CO2-based mixture refrigeration and heat pump systems composition adjustment scheme that adjusts the system's composition according to different working conditions. The paper designs two composition adjustment strategies, studies the limits of composition adjustment using different methods, and evaluates the energy-saving performance of different adjustment methods. The results show that the maximum range of composition adjustment is between.25 and.97， and the energy-saving of up to 27.2% can be achieved through composition adjustment in some areas. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Currently, approximately 40% of the energy demand in the European Union (EU) is used in buildings and the energy demand for cooling and heating is increasing every year, so the energy efficiency of buildings represents a problem of increased interest and of extreme relevance. The article proposes, through the case study, the installation of a photovoltaic system for the production of electricity on the roofs of the buildings and the cooling and heating of the building using a water-to-water heat pump. Having the advantage of the location of the studied buildings on the banks of the river Bega in the town of Timisoara, the case study proposes the cooling of the spaces in the buildings in two variants, namely in the spring and autumn when the outside temperature is not very high using the river water directly ("free cooling"), and in the summer for the hot months, a water-to-water heat pump to cool the cooling agent to the parameters necessary to achieve a proper air conditioning. [ABSTRACT FROM AUTHOR]

Copyright of Romanian Journal of Civil Engineering / Revista Română de Inginerie Civilă is the property of Matrix Rom and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemical Engineering (China) / Huaxue Gongcheng is the property of Hualu Engineering Science & Technology Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Industrial buildings have numerous kinds of energy-losing equipment, such as engines, ovens, boilers and heat exchangers. Energy losses are related to inefficient energy use and lousy work conditions for the people inside the buildings. This work is devoted to the recovery of lost energy from industrial buildings. Firstly, the residual energy of the building is extracted to be used to warm water. Consequently, the work conditions of the people inside industrial buildings can be improved by maintaining the adequate temperature. The recovery of the energy is performed by a multipurpose heat pump system (HP system). The working fluid used in the HP system is R134a, which is a traditional and cheap working fluid. The thermophysical properties of R134a are obtained through the PC-SAFT equation of state. This work presents a performance mapping based on the intercepted areas framework to evaluate which working conditions are the optimal operating variables. The latter depends on several key parameters, such as compressor work, heat delivery, heat absorbed and exergetic efficiency. The results show that the optimal work conditions are found at different condenser and evaporator temperatures, and these may be limited by what the designer considers a sound performance of the heat pump system. [ABSTRACT FROM AUTHOR]

Efficient and reliable utilization of renewable energy at the user's end is the key to achieving a low‐carbon life. This paper proposed a new distributed energy system around the comprehensive utilization of solar energy by integrating solid oxide fuel cell (SOFC), energy storage equipment, photovoltaic thermal (PVT) collector, and heat pump. By integrating the use of SOFC and PVT, we can further minimize reliance on fossil fuels, while employing the coupling of PVT and heat pump effectively mitigates the inherent challenges of solar energy's variability and intermittency, all while enhancing overall system efficiency. On this basis, we apply the heat current method to construct a cross‐scale heat current model of the components and the system by considering the energy transfer, conversion, and storage characteristics of the system. By employing this model, we simulate the system's operation throughout an entire typical day, assess the COP enhancement of the PVT‐coupled heat pump system, analyze the influence of diverse operating conditions on daily system performance, and evaluate the economy of the energy storage devices in the system. [ABSTRACT FROM AUTHOR]

Copyright of Food & Fermentation Industries is the property of Food & Fermentation Industries and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This experiment mainly used in-shell fresh peanuts as the main raw material and adopted heat pump drying technology to dry peanuts. The effects of different material temperatures, loading masses, and air velocities on drying characteristics and peanut kernel nutritional quality were compared. Results showed that during drying, the drying moisture ratio decreased exponentially with increasing drying time, and the drying rate decreased with time. With the increase in material temperature, the drying time decreases, and the unit energy consumption first decreases and then increases. With the increase in loading mass, the drying time increases, and the unit energy consumption first decreases and then increases. Air velocity had no significant effect on drying time and unit energy consumption. The material loading had no significant effect on the protein, fat, oleic acid, linoleic acid, and amino acid contents in peanut kernels. The material temperature and air velocity had a significant effect on the nutritional quality of peanut kernels. The acid value and peroxide value of the dried peanut kernels met the national standard. When the hot air temperature was 45 °C, the germination potential and rate of peanut kernels were the highest, and the material loading and air velocity had no significant effect on the germination rate. In conclusion, setting the drying conditions to a hot air temperature of 45 °C, a single loading amount of 1 000 g, and an air velocity of 1.2 m/s resulted in better drying characteristics and quality of peanut kernels, with a shorter drying time (10.0 h) and the lowest unit energy consumption (11.01 kW·h/kg). [ABSTRACT FROM AUTHOR]

Current energy efficiency regulations have led to the development of heat pumps equipped with variable speed compressors (VSC) and electronic expansion valves (EEV). To reduce the amount of refrigerant charge, heat pump manufacturers are developing units without a liquid receiver. As a result, the amount of refrigerant charge has a direct impact on the unit performance and needs to be optimized. Previous studies have shown the existence of an optimum refrigerant charge that maximizes the COP at a given operating condition. However, with VSC it is not clear if the optimum charge at a given compressor speed is the adequate one at other speed values. This paper analyzes the effects of the refrigerant charge amount on the performance of a brine-to-water heat pump equipped with a VSC and an EEV. For a given compressor speed, the variation of the COP with the charge showed similar trends and an optimum refrigerant charge could be identified. The charge for the maximum COP changes slightly with the compressor speed. The seasonal coefficient of performance (SCOP) is proposed as a better metric for evaluating the optimum charge. Results show that the SCOP is quite stable with the refrigerant charge. [ABSTRACT FROM AUTHOR]

The energy consumption of high carbon natural gas increases with the increase of carbon content when it is decarburized by the alcohol amine process. In order to reduce the energy consumption of high carbon natural gas, a carbon dioxide (CO2) capture coupled process (referred to as "coupled process") was proposed, which coupled the alcohol amine process (N-methyldiethanolamine as the absorbent) with inter-stage cooling, liquid rich shingle desorption, acid gas recompression heat pump and steam-mechanical recompression technology (MVR) heat pump processes. The key parameters, such as inter-stage flow cooling temperature, lean liquid throttling pressure, acid gas recompression pressure and regenerator bottom reboiler temperature, were analyzed by Aspen Hysys software, and the key parameters were optimized by response surface analysis and genetic algorithm. The results show that the inter-stage flow cooling temperature, the lean liquid throttling pressure, the acid gas compression pressure and the regenerator bottom reboiler temperature is 58 °C, 0.0844 MPa, 0.195 MPa and 92 °C, respectively. Compared with the combined process (membrane separation + alcohol amine method), the energy consumption of the coupled process is significantly reduced, and the unit energy consumption of decarbonization (the energy required to remove 1 t CO2) decreases from 1.338 GJ/t to 1.110 GJ/t. Compared with before optimization, the CO2 content (volume fraction) in the purified gas of coupled process after optimization decreases from 2.533% to 2.326%, and unit energy consumption decreases from 1.110 GJ/t to 1.074 GJ/t. [ABSTRACT FROM AUTHOR]

The CO2 phase change capture process has low regeneration energy consumption, but in actual production, the CO2 content (mole fraction, the same below) in flue gas generated by the upstream process is unstable, which can lead to changes in the overall energy consumption of the process. Therefore, it is necessary to study the adjustment strategies of the process parameters under different CO2 content of flue gas. Using Python to invoke Aspen Plus to simulate the near isothermal CO2 capture technology, and the effects of adsorption tower temperature (ta), desorption tower temperature (td), liquid/gas ratio (v), amine concentration (c) and desorption liquid circulation ratio (s) on the regeneration energy consumption and CO2 capture rate and the corresponding regulation strategies were analyzed. The results show that td has the most significant effect on CO2 capture rate, and the correlation coefficient is the highest (74.78%) when the CO2 content is 5.00%. ta has the most significant impact on regeneration energy consumption, and when CO2 content is 20.00%, its correlation coefficient is the highest (-55.26%). With the CO2 content increases from 5.00% to 20.00%, the regeneration energy consumption decreases from 2.35 GJ/t to 2.13 GJ/t under the condition that the CO2 capture rate is greater than 90.00%. In addition, ta, td, c and v should be adjusted accordingly according to CO2 content to ensure that CO2 capture rate is greater than 90.00% and the regeneration energy consumption is lowest. [ABSTRACT FROM AUTHOR]

At present, the energy consumption of the whole process of buildings in China accounts for 45 % of the total energy consumption of the country, and the carbon emissions account for 50.6 % of the total emissions of the country. Among the energy consumption of buildings, air conditioning energy consumption occupies a major proportion, about 2/3. Traditional air conditioning cooling mainly uses refrigerants such as Freon to circulate and cool under high temperature and high pressure, which not only has high energy consumption but also can cause the external environment temperature to be too high. River water source heat pump is a renewable energy technology that can use water bodies including groundwater, surface water such as rivers, lakes, reservoirs and oceans. This project mainly studies the operation strategy of related units using river water as the cold source in a chemical industrial park in Chongqing, from unit selection, establishment of energy consumption model to unit operation strategy analysis and research, to achieve the best state of energy utilization. [ABSTRACT FROM AUTHOR]

Heat pumps (HPs) have emerged as a key technology for reducing energy use and greenhouse gas emissions. This study evaluates the potential switch to air-to-air HPs (AAHPs) in Toulouse, France, where conventional space heating is split between electric and gas sources. In this context, we find that AAHPs reduce heating energy consumption by 57% to 76%, with electric heating energy consumption decreasing by 6% to 47%, resulting in virtually no local heating-related CO2 emissions. We observe a slight reduction in near-surface air temperature of up to 0.5 °C during cold spells, attributable to a reduction in sensible heat flux, which is unlikely to compromise AAHPs operational efficiency. While Toulouse's heating energy mix facilitates large energy savings, electric energy consumption may increase in cities where gas or other fossil fuel sources prevail. Furthermore, as AAHPs efficiency varies with internal and external conditions, their impact on the electrical grid is more complex than conventional heating systems. The results underscore the importance of matching heating system transitions with sustainable electricity generation to maximize environmental benefits. The study highlights the intricate balance between technological advancements in heating and their broader environmental and policy implications, offering key insights for urban energy policy and sustainability efforts. Switching to air-to-air heat pumps in Toulouse cuts energy use and eliminates CO2 emissions. While efficiency is high, cities transitioning from fossil fuel heating may see increased electricity use, stressing the need for sustainable power sources. [ABSTRACT FROM AUTHOR]

The use of renewable energy by converting it into heat is an important form of storing energy in a usable form and improving the energy supply flexibility; therefore, the electricity–heating system (EHS) can cope with load fluctuations. However, relevant research is lacking on improving the energy supply limitations by the optimal dispatch of energy flow at the typical EHS, such as the coupled CHP–heat pump–thermal storage system (CCHTS). Based on the study of the energy supply characteristics of the CCHTS for extending the energy supply limitation, this study develops an optimal dispatch method using a heat pump (HP) and the thermal storage (TS) of heating networks to improve the flexibility of the CCHTS and the accommodation capacity of renewable energy. The maximum and minimum energy supply limitation model of the CCHTS and the output power characteristic model are established. Based on the piecewise power supply constraint, the energy flow of the EHS is optimized by using the quadratic programming algorithm. The CCHTS can significantly improve the energy supply flexibility; both coupled combined heat and power (CHP) + HP and coupled CHP + TS can improve the power supply flexibility, but the enhanced effect of CHP + HP is better than that of CHP + TS. An increase of 7.6% in wind power consumption is achieved. The consumption of renewable energy increases by 17.9% in the energy flow optimization results. [ABSTRACT FROM AUTHOR]

To address the challenges posed by global climate change, developing green energy systems characterized by informatization, digitalization, and intelligence is crucial for achieving carbon neutrality. This article is a research report type paper on water source heat pump (WSHP) energy stations, aiming to use digital twin technology and other information technologies to resolve conflicts between clean energy development and efficient energy utilization. The primary objective of this study is to identify and analyze issues in traditional energy station operations and management systems. Based on this analysis, specific technical solutions are proposed, including pathways for technological research, methodologies, and content. The results provide a comprehensive theoretical framework for the intelligent transformation of energy station systems and essential technical support for the WSHP energy station project in the Hankou Binjiang International Business District. The findings have significant implications for the widespread adoption of WSHP energy stations and the achievement of national carbon neutrality goals. [ABSTRACT FROM AUTHOR]

To tackle the variability of distributed renewable energy (DRE) and the timing differences in load demand, this paper perfects the integrated layout of "source-load-storage" energy control in virtual power plants (VPPs). Introducing a comprehensive control approach for VPPs of varying ownerships, and encompassing load aggregators (LAs), a robust and cost-efficient operation strategy is proposed for VPP clusters. Initially, the influence of real-time electricity prices on cluster energy utilization is taken into account. Flexible shared electricity prices are formulated cluster-wide, based on the buying and selling data reported by each VPP, and are distributed equitably across the cluster. Following this, a flexible supply and demand response mechanism is established. With the goal of minimizing operational costs, this strategy responds to demand (DR) on the end-user side, instituting shifts and reductions in electricity and heat loads based on electricity and heat load forecasting data. On the supply side, optimization strategies are developed for gas turbines, residual heat boilers, and ground-source heat pumps to restrict power output, thus achieving economical and low-carbon cluster operations. Finally, the efficacy of the proposed optimization strategy is demonstrated through tackling numerous scenario comparisons. The results showcase that the proposed strategy diminishes operational costs and carbon emissions within the cluster by 11.7% and 5.29%, respectively, correlating to the unoptimized scenario. [ABSTRACT FROM AUTHOR]

A uniform and constant energy source with the newly developed energy column In order to air‐condition our buildings in the future, we must use renewable energies. The heat pump will be an important factor on the way there making use of various renewable energy alternatives as an energy source. The performance of the heat pump is determined by the temperature difference between the source and room temperatures. The lower this value is, the lower the power consumption. The method presented here represents a form of intermediate storage for collecting radiant energy. The temperature in the storage is raised to a higher level than the output sources. If thermal energy is needed, the heat pump can always rely on a source with a high temperature level. The presented energy column is able to collect energy from radiation at a high temperature level. The two associated heat storage units store the heat energy generated as input for the heat pump when heating. If there is excess electricity, the temperature level in the two storage units is raised. [ABSTRACT FROM AUTHOR]

Copyright of International Journal of Engineering Research & Development (IJERAD) is the property of International Journal of Engineering Research & Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Drying food stuffs and other materials belongs to one of the most commonly used feedstock processing techniques, featuring rather high energy consumption. The major disadvantage of conventional electric convective-type household dryers is substantial thermal energy emission into the environment with a wet exhaust, worked-out drying agent. Among other principal disadvantages common to all dryers of this type, the following have to be mentioned: spatial inhomogeneity of heating a product under processing and that of drying agent distribution due to its temperature reduction and relative humidity growth as it moves upwards. A block diagram and a breadboard model of a convective-type thermoelectric dryer employing a thermoelectric heat pump have been designed. In our approach, a product is treated with the help of a drying agent (normally, heated air) with partial exhaust-air recirculation and heat recovery. Laboratory studies of the drying process have been carried out using apple fruits as a test material in order to evaluate the power consumed for evaporation of 1 kg of water in the newly developed convective-type thermoelectric drying unit. Physical parameters of apple fruits before and after drying both in the thermoelectric drying unit and in a conventional series-produced convective-type domestic dryer have been reported. The energy efficiency of the newly designed drying unit has been compared with that of some series-produced samples. It has been found out that, unlike conventional convective-type dryers, the breadboard model of the developed thermoelectric drying unit features a smoother product drying process owing to the presence of side air channels and more effective drying agent path organization in the processing chamber. This conclusion was supported by the results of the carried out tests. Application of thermoelectric heat pumps with the function of the exhaust drying agent heat recovery will make it possible to reduce the drying agent heater installed capacity and the power consumed by the newly designed convective-type thermoelectric drying unit by up to 20% in the course of the drying process, compared to series-produced household convective-type dryers. [ABSTRACT FROM AUTHOR]

The European Union faces the pressing challenge of decarbonising the buildings sector to meet its climate neutrality goal by 2050. Buildings are significant contributors to greenhouse gas emissions, primarily through energy consumption for heating and cooling. This study uses the advanced PRIMES-BuiMo model to develop state-of-the-art innovative pathways and strategies to decarbonise the EU buildings sector, providing insights into energy consumption patterns, renovation rates and equipment replacement dynamics in the EU and in two representative Member States, Sweden and Greece. The model-based analysis shows that the EU's transition towards climate neutrality requires significant investment in energy efficiency of buildings combined with decarbonisation of the fuel mix, mostly through the uptake of electric heat pumps replacing the use of fossil fuels. The Use Case also demonstrates that targeted policy interventions considering the national context and specificities are required to ensure an efficient and sustainable transition to zero-emission buildings. The analysis of transformational strategies in Greece and Sweden provides an improved understanding of the role of country-specific characteristics on policy effectiveness so as to inform more targeted and contextually appropriate approaches to decarbonise the buildings sector across the EU. [ABSTRACT FROM AUTHOR]

Building energy consumption in China accounts for 45% of the total national energy consumption, with air conditioning energy consumption representing approximately two-thirds of that. Therefore, energy efficiency in buildings is of utmost importance. This study focuses on a chemical industrial park located along the Fujiang River and compares three heating and cooling supply schemes: the river water source heat pump system, which utilizes river water as the heat source and heat sink; the water cooling unit and boiler system, which uses water-cooled electric compression chillers for cooling and an oil-fired boiler system for heating; and the split air conditioning and gas water heater scheme, which relies on refrigerants such as fluorine-containing compounds for cooling and a gas water heater for heating. By calculating the energy consumption of the above three schemes and conducting a comparative analysis, it is found that the river water source heat pump system exhibits significantly higher energy efficiency throughout the year compared to the water cooling unit and boiler system and the split air conditioning and gas water heater scheme. This highlights the notable energy efficiency advantage of the river water source heat pump system. [ABSTRACT FROM AUTHOR]

In this study, the thermal comfort and energy consumption of two different terminal units when combined with three different water supply temperatures were studied. Results showed that convection–radiation combined cooling terminals can increase the water supply temperature under the same thermal comfort level compared with convection cooling terminals. When the water supply temperature was fixed at 11 °C, the energy consumption of convection–radiation combined cooling terminals was 9.1 % lower than that of convection cooling terminals. The higher the water supply temperature, the lower the energy consumption under convection–radiation combined cooling terminals. Furthermore, the energy consumption rates at a water supply temperature of 15 °C were 18.2 % and 8.8 % lower than those at 7 °C and 11 °C, respectively. Meanwhile, the comfort and system operation efficiency were optimal when the water supply temperature was 15 °C, and the energy consumption was lower when combined with the cooling of the dual terminals. [ABSTRACT FROM AUTHOR]

Neutral-temperature district heating and cooling (NT-DHC) is a recent concept in the district heating sector. The current literature does not directly address the ability to create comprehensive master plans for NT-DHC systems and reliably model their performance. This research presents a new approach for the evaluation and planning of NT-DHC systems. The methodology involves the use of a knapsack optimization algorithm to perform a comprehensive analysis of the conditions that make the NT-DHC solution competitive against individual heating and cooling technologies. The algorithm determines the optimal combination of potential extensions that maximizes overall economic value. The results of a case study, which was conducted in Italy, show that NT-DHC is more suitable in dense urban areas, while air-to-water heat pumps are better suited for low heat density zones. This methodology aims to reduce the risks associated with energy demand and provide more certainty about which areas a network can expand into to be competitive. It is targeted at energy planners, utilities experts, energy engineers, and district heating experts who require assistance and guidance in the planning and early stages of designing a NT-DHC system. This method might enable pre-feasibility studies and preliminary design to determine the opportunities and limitations of a system of this kind from an economic and technological perspective. [ABSTRACT FROM AUTHOR]

This article aims to demonstrate the technical capabilities and effectiveness of an energy production and management system for school facilities using a modular solution. The system is assumed to generate electricity from renewable sources, such as wind or sun. The potential of renewable energy sources in Cracow, Poland, was assessed, with a focus on solar energy (photovoltaic panels, PV). Taking into account the installation of heating and other equipment, an analysis of the facility's electricity demand was carried out. The study recommended the use of a heat pump system to heat and cool the facility. Renewable energy sources will meet 81% of the facility's projected annual demand, according to the study. An analysis of the energy consumption and production profiles shows that almost 69% of the energy produced by the PV panels is consumed on site. Of the remaining energy, 31% is fed back into the grid and sold to the grid operator or used by other facilities within the shared settlement. The overall balance results in a small electricity deficit that must be covered by the grid. If suitable sites are available, the facilities under study could consider installing a wind turbine as a potential supplement to the energy deficit. [ABSTRACT FROM AUTHOR]

Heat pumps are an important tool in reducing carbon emissions, but they currently only meet a small fraction of global heating needs in buildings. Retrofitting heat pumps in commercial and industrial settings is challenging due to lack of knowledge, high costs, and structural barriers. Despite increased sales, heat pumps are not being deployed at the necessary levels to achieve net zero emissions. The European Heat Pump Association has released a manifesto calling for policy changes and government incentives to increase adoption. They highlight the need for stable policy support, adjustments to energy taxation, and regulatory advancements to ensure compliance with environmental standards. Overcoming obstacles in innovation, education, training, and legislation is crucial, with the political arena being the most important in driving industry uptake. [Extracted from the article]

With the development of Chinese society, there is an increasing demand for emissions reduction and the stable operation of the power grid. Regional comprehensive energy supply systems have entered the public's view owing to their advantages of reducing capacity, unified dispatch, improving efficiency, and reducing energy consumption. This paper focuses on a system under construction in Chongqing, which adopts a combined gas tri-supply (combined cooling, heat, and power, CCHP) and dynamic ice storage cooling system as the research object. By establishing a mathematical model for the simulation research, this study examines the start–stop priority sequence of the gas tri-supply subsystem and the heat pump subsystem under the ice storage priority strategy in winter and summer and proposes corresponding optimization solutions. By comparing the annual operating energy consumption of the system, we conclude that the gas tri-supply composite system has good economic efficiency and peak-shaving capability, indicating that regional gas tri-supply composite systems have great application potential in the future. The proposed optimized operation strategy and simulated energy consumption calculation provide theoretical guidance for the construction and operation of both this project and similar projects. [ABSTRACT FROM AUTHOR]

In this paper, a combined air/water source heat pump water heater is presented. At ordinary time, the heater can be used for hot water heating in water-source mode to improve the energy efficiency. While in cold season, it gives priority to air-source mode for water heating to improve operational safety. Experiments were conducted to investigate the thermodynamic performance of the heater in each operation mode, and the experiment results were analyzed. The research indicated that its operation was reliable during the long-time running. This paper offers a promising energy-saving method in future. [ABSTRACT FROM AUTHOR]

Optimizing hybrid thermal systems for domestic heating systems is essential to achieve maximum energy efficiency, lower carbon emissions, and decrease overall expenses. This research focuses on utilizing solar energy through evacuated tube solar water systems in conjunction with fuel-based (LPG or diesel) boilers or electric heat pumps for heating residential homes in various climate zones across Jordan. The contributions of each subsystem of thermal energy production were assessed using a one-year dynamic simulation using simulation software TSOL and Meteonorm. A variety of optimization methods are then employed to study and compare several parameters, including station rankings as well as technical and environmental factors. The optimization methods Best-Worst Method BWM yields the highest and lowest weights for the total solar fraction and solar contribution to heating, respectively. After station rankings were conducted using the ARAS, VIKOR, TOPSIS, MOORA, and AHP methodologies, the Maan and Amman stations were identified as most relevant and inappropriate for ETSW use. The annual production of 115.38 GJ utilizing ETSW at the stations under study reduced CO2 emissions by 12.18 tons. The largest losses, accounting for 60.25% and 33.86% of the total losses, respectively, were identified as thermal and optical losses for Maan station. Thus, this study's findings demonstrate the potential of optimized hybrid thermal systems, integrating solar energy with conventional heating methods, to significantly enhance energy efficiency, reduce carbon emissions, and lower overall expenses in residential heating across diverse climate zones in Jordan. [ABSTRACT FROM AUTHOR]

Heat pumps are a solution for decarbonising home heating in the UK. However, the readiness of UK homes for heat pumps is an area of concern regarding the policies aimed at increasing heat pump adoption. This work combines multiple perspectives in evaluating the technical readiness of homes with the market readiness of installers and homeowners to proceed with installing heat pumps. The effectiveness of past heating and energy efficiency policies in the UK are reviewed, along with building regulations, incentives to promote energy efficiency and the effectiveness of heat pump technology in heating homes. Current policies support the cost of a heat pump but home improvements to make homes 'heat pump-ready' can be necessary to achieve optimal heat pump system performance. This paper suggests the UK will face three major challenges. First, analysis highlights an 'eligibility-readiness gap' describing the difference between homes 'eligible' (50%) for the Government's Boiler Upgrade Scheme—a subsidy for heat pump installations—and the likely level of homes that are heat pump-ready (11%) for successful heat pump installations. Second, semi-structured interviews with heat pump installers identified gaps in capacity to deliver the necessary works to make homes heat pump-ready. As small or medium enterprises, the majority of installers do not currently see adding home improvement services to their existing business model as beneficial. All installers highlighted the need for Government to address the cost of electricity relative to gas. Third, a national survey of homeowners in England with gas boilers (n = 1,021) revealed low awareness of the necessary work to make homes heat pump-ready and low willingness to spend money on them unless supported by Government. This paper shows that the processes and costs involved in making homes heat pump-ready before successful design and installation are underappreciated by homeowners, inadequately served by industry, and insufficiently supported by Government. [ABSTRACT FROM AUTHOR]

In this study, we investigated the performance of air-to-water heat pump (AWHP) and energy recovery ventilator (ERV) systems combined with photovoltaics (PV) to achieve the energy independence of a dormitory building and conducted an analysis of the energy independence rate and economic feasibility by using energy storage devices. Our data were collected for 5 months from July to November, and the building energy load, energy consumption, and system performance were derived by measuring the PV power generation, purchase, sales volume, AWHP inlet and outlet water temperature, and ERV outdoor, supply, and exhaust temperature. When analyzing representative days, the PV–AWHP integrated system achieved an energy efficiency ratio (EER) of 4.49 and a coefficient of performance (COP) of 2.27. Even when the generated electrical energy exceeds 100% of the electricity consumption, the energy self-sufficiency rate remains at 24% due to the imbalance between energy consumption and production. The monthly average energy self-sufficiency rate changed significantly during the measurement period, from 20.27% in November to 57.95% in September, highlighting the importance of energy storage for self-reliance. When using a 4 kWp solar power system and 4 kWh and 8 kWh batteries, the annual energy self-sufficiency rate would increase to 67.43% and 86.98%, respectively, and our economic analysis showed it would take 16.5 years and more than 20 years, respectively, to become profitable compared to the operation of an AWHP system alone. [ABSTRACT FROM AUTHOR]

Further advances in hardware and software features are needed to optimize battery and thermal management systems to allow for the execution of longer trips in electric vehicles. This paper assesses the economic and environmental impacts of the following features: eco-charging, eco-driving, smart fast charging, predictive thermal powertrain and cabin conditioning, and an advanced heat pump system. A Total Cost of Ownership (TCO) and externalities calculation is carried out on two passenger cars and one light commercial vehicle (LCV). The energy consumption data from the vehicles are based on experiments. The analysis shows more benefits for the LCV, while the smart fast-charging feature on the car shows a slight increase in TCO. However, negative results did not contribute significantly compared to the ability to install a smaller battery capacity for similar use. [ABSTRACT FROM AUTHOR]

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Sustainable energy presently represents the energy of the future, which should be based on the application respecting the importance of energy priorities, increasing regional self-sufficiency, regional control of energy, and regulation of resource use. In the area of energy supply, the use of RES has been increasingly popular, mainly due to the instability in the energy market and the political situation worldwide. Paper's ambition is to evaluate the efficiency of the selected RES use in the specific conditions of Slovakia, with the aim to achieve the EU targets. This is important due to the increasing use of RES in Slovakia. The objective of this paper is achieved through an analysis of the energy profit of the RES system, comparing the costs of the proposed solutions. The evaluation is carried out by calculating the energy and economic efficiency of three possible buildings used in the research. Using the data obtained, the results show the most suitable alternative for each building. The resulting findings provide a valuable insight for governments in identifying the best projects for RES use. The result will be methodology creation as a base for local administration and communities to elaborate plans with a goal to extend RES use. [ABSTRACT FROM AUTHOR]

Heat pumps driven by sustainable electricity sources have been identified as a technology that can contribute to reduce carbon dioxide emissions. Furthermore, a heat pump can also provide energy savings when combined with a thermal energy storage system. Heat pumps can optimize their efficiency by accumulating thermal energy during periods of lower electricity demand, resulting in shorter operational durations and decreased overall energy consumption. In this work, the combination of a latent heat storage system with an air-water heat pump has been numerically analysed and experimentally tested. A phase change material (PCM) heat exchanger with an immersed plate was designed using a 3D CFD model (COMSOL Multiphysics®). The heat exchanger configuration with six steel plates immersed in the phase change material tank was proposed to enhance heat transfer in the storage system. The developed model is validated against experimental data from a real case study, demonstrating a maximum error of approximately 3% during the discharging phase. Additionally, the study explores the effects of different inlet heat transfer fluid temperatures and flow rates on the PCM solidification time. [ABSTRACT FROM AUTHOR]

In order to understand the energy-saving system of building cooling and heating integration, the author proposes a research on an energy-saving system of building cooling and heating integration based on building information modelling (BIM) technology. The author first analyzed the energy-saving performance of the system by establishing models for each module based on meteorological data simulated on the DeST software platform. Secondly, in order to analyze the energy consumption of the integrated system, it is necessary to establish a residential building model, and select the building model in the cold winter and hot summer areas of a city for analysis. The results show that due to the system's heat storage function, there is no need to consume electricity in spring and autumn. Compared to the electric heating hot water mode, the integrated system can save 1198.85 kWh of electricity in non-cooling and heating seasons, with a 100% energy-saving rate. Compared to not using an integrated system, it can achieve an energy-saving rate of 81.9% throughout the entire refrigeration and heating season, with significant energy-saving effects. The integrated heating, cooling and hot water system of BIM technology adopts the technology of cool storage and heat storage coupled with solar energy and heat pump technology. The system has simple structure, obvious energy-saving effect, good environmental protection, and can adapt to various climates throughout the year. The introduction of underfloor heating also increases the comfort of buildings and residences. [ABSTRACT FROM AUTHOR]

Along with the rapid economic development and social progress, the problem of energy and environment is becoming more and more outstanding. Therefore, it is very important to use new energy saving techniques to increase energy consumption and reduce energy consumption. In this paper, we have developed a hot water system, which is based on solar energy technology, gas-source heat pump, and phase change energy storage technology. The system was designed and constructed, and its performance was tested in various control conditions, with an emphasis on the analysis of the influence of phase change heat supply on heat storage properties. In this paper, the effect of the heat storage property is analyzed. Studies have shown that compared to a conventional tank that does not have a phase change heat storage device, the heat storage tanks equipped with phase change energy storage devices have longer discharge time, higher discharge temperature, better temperature, and better operation efficiency. In addition, the data show that flow rate control is also an important factor in optimizing the thermal storage characteristics of the system. [ABSTRACT FROM AUTHOR]

In light of the global industrial sector's steadfast pursuit of sustainable solutions to mitigate carbon emissions and efficiently minimize energy inefficiencies, the significance of novel approaches to energy optimization becomes increasingly evident. This research presents a novel digital twin concept that is designed to enhance the efficiency and effectiveness of high-temperature heat pumps in industrial renewable energy systems. Through the utilization of real-time data and complex computer modeling techniques, our proposed digital twin model seamlessly presents a comprehensive perspective on energy flows. This approach identifies inefficiencies and delivers practical insights to mitigate waste. The incorporation of this approach into pre-existing eco-conscious renewable energy systems has the potential to greatly enhance the effectiveness, predictability, and long-term viability of industrial processes. The empirical findings, obtained from multiple case studies conducted in industrial settings, provide evidence of the potential benefits in terms of energy waste reduction, and maximize the durability of systems. The results of our initial studies provide a foundation for the utilization of digital twin technologies in the field of industrial renewable energy systems optimization, representing a significant advancement towards a more environmentally sustainable industrial landscape. [ABSTRACT FROM AUTHOR]