scholarly journals Performance Evaluation of a Solar Hybrid Air-Conditioner

Author(s):  
Nnamdi Cyprian Nwasuka ◽  
Nduka Nwankwojike ◽  
Uchechukwu Nwaiwu

Abstract This research presents a solar hybrid air-conditioning system with R410a refrigerant. The sole aim was to compare the performance of a solar hybrid air-conditioner with that of the conventional split-unit air-conditioning systems in the market today. From the experiments conducted, the room temperature of a solar hybrid air conditioner was found to be :27.2, 27.0, 27.0, 27.2, 27.2, 27.0, 28.0, and 29.5 while that of the conventional air conditioner was found to be:69,66,64,66,73,69,66,62 indicating that solar hybrid system had lower values in terms of room temperature than that of the split units air conditioner. Laboratory results, field assessments, and simulations clearly established that hybrid air conditioners can deliver substantial energy savings and demand reduction. Therefore, in the present study, performance evaluation of the solar hybrid system with that of the split units is used to develop approximate analytical solutions for heat transfer in boundary layer flow and heat transfer.

2014 ◽  
Vol 699 ◽  
pp. 828-833 ◽  
Author(s):  
Sumeru ◽  
Markus ◽  
Farid Nasir Ani ◽  
Henry Nasution

Air conditioning system consumes approximately 50% of the total energy consumption of buildings. Split-type air conditioner is the most widely used in residential and commercial buildings. As a result, enhancement on the performance of the air conditioners will yield a significant energy savings. The use of ejector as an expansion device on the split-type air conditioners is one method to increase the system performance. Exergy analysis on a split-type air conditioner uses an ejector as an expansion device at room and outdoor temperatures of 24 °C and 34 °C, respectively, yielded the percentage of exergy reduction up to 40.6%. Also, the exergy losses on in the compressor had the highest impact on the performance improvement of the split-type air conditioner.


Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4663
Author(s):  
Tatsuhiro Yamamoto ◽  
Akihito Ozaki ◽  
Myonghyang Lee

The number of houses with large, continuous spaces has increased recently. With improvements in insulation performance, it has become possible to efficiently air condition such spaces using a single air conditioner. However, the air conditioning efficiency depends on the placement of the air conditioner. The only way to determine the optimal placement of such air conditioners is to conduct an experiment or use computational fluid dynamic analysis. However, because the analysis is performed over a limited period, it is difficult to consider non-stationarity effects without using an energy simulation. Therefore, in this study, energy simulations and computational fluid dynamics analyses were coupled to develop a thermal environment analysis method that considers non-stationarity effects, and various air conditioner arrangements were investigated to demonstrate the applicability of the proposed method. The accuracy verification results generally followed the experimental results. A case study was conducted using the calculated boundary conditions, and the results showed that the placement of two air conditioners in the target experimental house could provide sufficient air conditioning during both winter and summer. Our results suggest that this method can be used to conduct preliminary studies if the necessary data are available during design or if an experimental house is used.


2017 ◽  
Vol 140 (1) ◽  
Author(s):  
Carlos R. de Nardin ◽  
Felipe T. Fernandes ◽  
Adriano J. Longo ◽  
Luciano P. Lima ◽  
Felix A. Farret ◽  
...  

This paper presents a comparison of air conditioners using the conventional heating, ventilation, and air conditioning heat pumps and the one using solar heat stored underground, also known as shallow geothermal air conditioning. The proposed air conditioner with solar heat stored underground reunites practical data from an implementation of the heuristic perturb-and-observe (P&O) control and a heat management technique. The aim is to find out the best possible heat exchange between the room ambient and the underground soil heat to reduce its overall consumption without any heat pump. Comparative tests were conducted in two similar rooms, each one equipped with one of the two types of air conditioning. The room temperature with the conventional air conditioning was maintained as close as possible to the temperature of the test room with shallow geothermal conditioning to allow an acceptable data validation. The experiments made both in the winter of 2014 and in the summer of 2015 in Santa Maria, South Brazil, demonstrated that the conventional air conditioner consumed 19.08 kWh and the shallow geothermal conditioner (SGC) consumed only 4.65 kWh, therefore, representing a reduction of energy consumption of approximately 75%.


2019 ◽  
Vol 3 (3) ◽  
pp. 267
Author(s):  
Andi Asrul Sani ◽  
Adelia Enjelina Matondang ◽  
Guruh Kristiadi Kurniawan ◽  
Anggi Mardiyanto

Abstract: The use of glass material should consider the comfort of space in the building. Field of glass is needed as natural lighting and visual facilities between the occupants and the surrounding environment. Its function as natural lighting is often accompanied by an increase in temperature in buildings, considering that Indonesia is a tropical country. Building temperatures that increase due to incoming sunlight can cause discomfort to building occupants. Such conditions make building occupants use air conditioner (AC). The use of air conditioners can increase the value of building energy consumption. For this reason, research on the value of heat transfer in buildings or the value of OTTV (Overall Thermal Transfer Value). OTTV value calculation is done by manual calculation. Bandar Lampung City lecture building at the Sumatra Institute of Technology was chosen as the object of this study. From the results of the study found that the value of heat transfer of a building or OTTV (Overall Thermal Transfer Value) is influenced by the factor of the ratio of the window area to the facade or WWR (Window Wall Ratio) and the shading factor (Shading Coefficient).(Keywords: Keyword: energy consumption, building energy, glass. Abstract: Penggunaan material kaca semestinya mempertimbangkan kenyamanan ruang dalam bangunan. Bidang kaca diperlukan sebagai pencahayaan alami dan sarana visual antara penghuni dan lingkungan sekitar. Fungsinya sebagai pencahayaan alami seringkali disertai dengan peningkatan temperatur pada bangunan, mengingat Indonesia merupakan negara yang beriklim tropis. Temperatur bangunan yang meningkat akibat dari radiasi sinar matahari yang masuk dapat menyebabkan ketidaknyamanan bagi penghuni bangunan. Kondisi seperti itu membuat penghuni bangunan menggunakan air conditioner (AC). Penggunaan air conditioner tersebut dapat meningkatkan nilai konsumsi energi bangunan. Untuk  itu dilakukan penelitian mengenai nilai perpindahan panas dalam bangunan atau nilai OTTV (Overall Thermal Transfer Value). Penghitungan nilai OTTV dilakukan dengan penghitungan manual. Gedung kuliah Kota Bandar Lampung di Institut Teknologi Sumatera di pilih sebagai objek dalam penelitian ini. Dari hasil penelitian ditemukan bahwa nilai perpindahan panas suatu bangunan atau OTTV (Overall Thermal Transfer Value) dipengaruhi oleh faktor nilai perbandingan luas jendela terhadap bidang fasad atau WWR (Window Wall Ratio) dan faktor pembayangan (Shading Coefficient).Kata kunci : konsumsi energi, energi bangunan, kaca.


2019 ◽  
Vol 111 ◽  
pp. 06035
Author(s):  
Sihwan Lee

While air conditioner is running, opening doors and windows is a great way to reduce operating efficiency and undermine the air conditioning system’s ability to bring the indoor to a comfortable temperature. The purpose of this study is to evaluate the heat loss and thermal environment through the door open while air conditioner running. To achieve this goal, using full-scale measurement with the commercial store during the cooling period, the infiltration rate, thermal environment and energy consumption of air conditioners with door opened and door closed state were measured. The measured results show that the infiltration rate at the door opened state was increased by about 21.3 times compared to the door closed state. When the set temperature of the air conditioner was 24 °C, the room temperature in the opening gate cooling was measured to be about 5 °C higher than the closing gate cooling. However, the energy consumption was measured approximately 12 kWh/day and there was no difference with door state. This means that the energy consumption is not increased if the indoor air temperature would not reach the set point temperature of air conditioner.


2020 ◽  
Vol 28 (01) ◽  
pp. 2050008
Author(s):  
Vignesh Lakshmanan ◽  
Pushpak Doiphode ◽  
Indraneel Samanta

Inverter air conditioners are being widely used in the air conditioning sector for energy saving purposes. These air conditioners use an inverter or a variable frequency drive (VFD) to control the compressor operating speed based on cooling or heating load fluctuations. If the heat generated by the electronic components of the VFD is not dissipated properly, it can lead to failure of the VFD. In general, a heat sink is used for dissipating the heat generated by the electronic components of the VFD. The heat sink can be either air cooled or liquid cooled. Using computational fluid dynamics (CFD), this paper deals with optimization of the thermal performance of an air cooled plate-fin heat sink with rectangular fins used in a residential split inverter air conditioner. Commercially available CFD tool has been used for simulations. It has been observed that enhancing fluid flow around the heat sink and improving heat transfer area of the fins significantly improve the thermal performance of the heat sink. By using heat sink with rectangular fins having a stepped profile, it has been possible to improve the heat transfer from the baseline case by 27%. Whereas, by using hollow fins, heat transfer improvement of 20% has been achieved.


2018 ◽  
Vol 248 ◽  
pp. 01003
Author(s):  
Kaidir ◽  
Mulyanef ◽  
Burmawi

The Government of Indonesia has done some efforts to overcome energy crisis nationwide. Among them by issuing a policy as the Foundation for the development and improvement of the capacity of providing energy. The Government has issued a presidential instruction number 10 of the year 2005 on energy savings and last Presidential Instruction No. 2 of the year 2008 about saving energy and water. One of the implementation efforts of this energy crisis is overcome with effort saves energy consumption on the air conditioning with develop hybrids air conditioning, namely as the air conditioner at the same time to the water heating. This research is a new technology for energy saving of electricity. The purpose of this research is to produce a prototype of a hybrid energy efficient refrigeration machine that can be function simultaneously as the engine room air conditioner at the same time water heaters. Specific research targets to be achieved is the realization of a prototype of a hybrid air conditioning engine capacity 1.5 PK which can save energy around 60%. The method of research is the planning, creation, testing the performance of air conditioning machines of compression cycle steam hybrid.


Jurnal INFORM ◽  
2019 ◽  
Vol 4 (2) ◽  
Author(s):  
Rinabi Tanamal

Abstract— Air Conditioner (AC) is a system or machine designed to stabilize the air and air temperatures that cover a certain area. This study discusses how to find ways to improve Android-based system applications for air protection in Air Conditioning (AC), this method is used as a support in making decisions on damage to Air Conditioner (AC) on the main components, supporting components, electrical components and cooling materials (Refrigerant) in Air Conditioner (AC). To design the application, an expert system is needed. Expert system itself is a computer system that emulates the ability of human expertise (Sri Hartati and Sari Iswanti, 2008: 152). The purpose of this study is to be able to produce an expert system application that can help technicians to improve damage to the Air Conditioner (AC) so that users of Air Conditioning (AC) can also understand the damage that occurs in Air Conditioners (AC). The research inference method used in this expert system uses the Android-based Forward Chaining method. Forward Chaining is a strategy in finding data by collecting data or facts which will then be concluded to find the right solution or event to solve a problem. The shell expert system used is McGoo which will then be adopted into the Thunkable Android application. With the existence of this expert system aims to identify damage to the Air Conditioner (AC) and used as material in making decisions to help the users, especially the technicians in diagnosing the damage that is in the Air Conditioner (AC). The results of this study indicate that the existence of a hierarchy of decisions to detect damage to the Air Conditioner (AC) can be applied in the society and from the results of application testing it can be concluded that the application of this expert system will be a tool for users of Air Conditioners and technicians to diagnose damage to Air Conditioner (AC). 


2018 ◽  
Vol 931 ◽  
pp. 920-925
Author(s):  
Zohrab Melikyan ◽  
Naira Egnatosyan ◽  
Siranush Egnatosyan

Centralized air conditioning systems are widely used in buildings at present. In these conditioners, the outside air gets required temperature, humidity, purity, and other features, necessary for creating comfort microclimate in inside areas of houses, and by the help of fans and air ducts the processed air moves to all rooms of a building. As a result, the creation and maintenance of comfort conditions in buildings become complicated and expensive activity. From this point of view, it is becoming more expedient to install local air conditioners in each room instead of single central one for the whole building. For this reason new local air conditioner is developed.


Author(s):  
Stefano Bergero ◽  
Anna Chiari

It has been demonstrated in the literature that significant energy savings can be achieved in air-conditioning through the use of so-called hybrid systems, in which a chemical dehumidification system is combined with a vapour-compression heat pump. The advantage of such systems lies in the fact that the heat pump can operate at a higher evaporation temperature than that of a traditional system in which dehumidification is achieved through condensation, thereby achieving higher coefficients of performance. The hybrid system described in the present paper operates as follows: the air supplied to the conditioned ambient is simultaneously cooled and dehumidified in an air-solution membrane contactor. The LiCl solution is cooled by means of a vapour-compression heat pump using the refrigerant KLEA 410A. The solution is regenerated in another membrane contactor by exploiting the exhaust air and the heat rejected by the condenser. A study of the steady-state behaviour of the system in summer climatic conditions was carried out, on varying some significant operating parameters, such as the thermal efficiency of the heat exchangers, the outdoor temperature and the sensible load of the conditioned room. The performances of the hybrid system were compared with those of a traditional direct-expansion air-conditioning plant; the results of the simulations reveal that, in particular operating conditions, energy saving can exceed 50%.


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