The system design of window air conditioner does not evolve in one day. Due to the continous efforts are taken by the refrigeration and air conditionging professionals, successful and economic models of window air conditioners are currently used. This paper states about the development of window air conditioner with phase change material and water as refrigerants. Developed air conditioner was tested for its thermal performance achievement. Outcomes specify that thermal comfort acheivement was in satisfactory levels. Predicted mean vote and percentage of people dissatisfied values were calculated and the results were in the range of neutral to a slight cooling, according to Americal Society of Heating and Refrigeration and Air conditioning standard 55.

Piezoelectric energy harvesting from air conditioner compressors is a promising technology for generating renewable electricity. This study comprehensively compares the energy harvesting potential derived from mechanical vibrations in compressors across various air conditioner brands, harnessing piezoelectric systems. Initially, a data collection system rooted in Internet of Things (IoT) technology is employed to capture vibration signals from different branded air conditioner compressors. The acquired data undergoes pre-processing and is subsequently analyzed in MATLAB Simulink to gauge its energy harvesting potential through a piezoelectric framework. Notably, the maximum voltage harvested demonstrated strong positive correlations with both the compressor vibrational frequency (0.7892) and velocity (0.7855), emphasizing their role in determining available mechanical energy for conversion to electrical power. Furthermore, a moderate positive correlation (0.0659) was observed between the harvested voltage and the compressor's rated power, indicating its influence on energy conversion. An additional positive correlation (0.2839) between temperature and harvested voltage was attributed to the increased electrical conductivity of compressor materials at higher temperatures. Conclusively, the compressor's frequency and velocity emerged as primary determinants of the maximum voltage harnessed, with rated power having a less pronounced yet contributory effect. This research provides valuable insights for optimizing energy harvesting from air conditioner compressors, highlighting the pivotal role of operational parameters.

Three percent out of seventy percent of earth planet water is freshwater that one percent of that is accessible. Pollution is added to the water shortage crisis, so humans are thinking about new water resources and trying to obtain them. Rainfall in Gilan province is abundant but irregular, especially in Rasht city. Temperature and evaporation increase in the late spring and summer, also, rainfall decrease in that time. Meanwhile, all cities and villages of Gilan, especially Rasht and its suburbs, use the gas air conditioner, and using this cooling system in buildings is developing day by day. The research was carried out in a room with a square of 33 m2 at the temperature of comfort range of 20 °C using an air conditioner of the 28000 type. The water flow, temperature, and humidity were recorded hourly during the day and night, and statistical analysis (descriptive-analytical) was performed. Finally, a simple model was obtained from the existing relationship between climatic elements (temperature and humidity) with water flow. Temperature and water flow have a first-degree relationship and humidity and water flow have a second-degree relationship. The first-degree relationship showed that when the temperature decreases, the water flow increases so that a negative or inverse relationship is created. But in the second relation, with increasing humidity, Water flow increases, and with decreasing humidity, the flow decreases. Temperature as an independent and main factor has an inverse effect on water flow and humidity. Finally, the data (temperature, humidity, and water flow) were classified in SPSS software. By setting the temperature and humidity data in one of the groups, the amount of water obtained from the air conditioner (flow) is well predicted, and it can be generalized. The average amount of water obtained from the air conditioner is about 30 Lit/hr for an area of 33 m2. Using more air conditioners in more areas will obtain more water flow which will meet a big part of the needs of families.

The world is looking towards producing products which consume less power without compromising on quality of life. The increase in use of refrigeration and air conditioning appliances are contributing to global warming. The world wide temperatures are shooting up at an increasing rate. This paper presents a design of roll bond evaporator as the heat exchanger to provide cooling in room air conditioner. Presently all room air conditioners use tube and fin evaporators. This study presents roll bond evaporator as a power saving alternative to tube and fin evaporator. The experimentation has been done and comparative study of roll bond evaporator with that of tube and fin evaporator is presented. It was found out that while the tube and fin evaporator took 30 minutes to get a uniform temperature of 25 º C in the room, the roll bond evaporator took only 25 minutes to get that uniform temperature, thereby saving 5 minutes of running of air conditioner.

In a 10-ton capacity pilot plant solar liquid desiccant air conditioner (LDAC) developed, dehumidification of the outside air is achieved through a honeycomb packed-bed heat and mass exchanger, using lithium chloride solution as the desiccant. The dry air obtained from the dehumidification process is evaporative cooled inside a cooling pad and directed into the conditioned space. The dilute solution thus produced and is concentrated in a honeycomb packed-bed scavenger air regenerator using hot water from flat plate solar collectors. Carryover the desiccant particles has been avoided by using eliminators. The air conditioner was installed in a 250 m2 area of the fluid mechanics laboratory of Babol University of Technology, a hot and humid location in the north on the Caspian Sea. The obtained experimental data was compared with the predicted results of a model developed for the air conditioner based on HYSIS and CARRIER energy soft-wares. The comparison reveals that there is good agreement between the experiments and the model predictions. The above tests further reveal that the unit has a satisfactory performance in independently controlling the air temperature and humidity of the conditioned space. The inaccuracies are well within the measuring errors of the temperature, humidity and the air and solution flow rates. An efficient heat recovery within the air conditioner resulted in a thermal COP of about 1. 5 and an electrical COP of 7. A commercialization study reveals that the operating cost of an LDAC is significantly lower than its conventional counterpart. The costs would further reduce if a storage system was used to store the concentrated solution of liquid desiccant. A simple payback of five years was determined for the solar components of the liquid desiccant system in this study.