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Previous works revealed that cross-corrugated absorber plate design and jet impingement on a flat absorber plate resulted in a significant increase in the performance of a solar air heater (SAH). Involving these two designs into one continuous design to improve the SAH performance remains absent in the literature. This study aimed to evaluate the achieved enhancement on performance parameters of a SAH with jet impingement on a corrugated absorber plate. An energy balance model was developed to compare the performance parameters of the proposed SAH with the other two SAHs. At a clear sky day and a mass flow rate of 0.04 kg/s, the hourly results revealed that the max fluid outlet temperatures for the proposed SAH, jet-to-flat plate SAH, and cross-corrugated plate SAH are 321, 317, and 313 K, respectively; the max absorber plate temperatures are 323.5, 326.5, and 328 K, respectively; the maximum temperature differences between the absorber plate and fluid outlet are ~3, 9, and 15 K, respectively; the max efficiencies are 65.7, 64.8, and 60%, respectively. Statistical t -test results confirmed significant differences between the mean efficiency of the proposed SAH and SAH with jet-to-flat plate. Hence, the proposed design is considered superior in improving the performance parameters of SAH compared to other designs.

PV/T technology attracted numerous researchers and professionals during the last decades. There are many review papers in the literature evaluated the R&D aspects of PV/T collectors. In fact, there are abundant of case studies discussed the parameters of climate, design and operational conditions affected the PV/T collector performance. But, a comprehensive compilation of the information of those case studies is still a missing link in the literature. Hence, this paper intended to review thoroughly the information regarding the parameters affecting the PV/T collector performance mainly and PV module performance partially. The parameters are supported with the most available R&D to measure the accurate influence of each parameter on the performance. The outcomes from the study are highlighted in lessons learned section.

A conceptual design and performance of a dual-purpose solar continuous adsorption system for domestic refrigeration and water heating is described. Malaysian activated carbon and methanol are used as the adsorbent–adsorbate pair. The heat rejected by the adsorber beds and condensers during the cooling process of the refrigeration part is recovered and used to heat water for the purpose of domestic consumption. In a continuous 24-h cycle, 16.9 MJ/day of heat can be recovered for heating of water in the storage tanks. In the single-purpose intermittent solar adsorption system, this heat is wasted. The total energy input to the dual-purpose system during a 24-h operation is 61.2 MJ/day and the total energy output is 50 MJ/day. The latter is made up of 44.7 MJ/day for water heating and 5.3 MJ/day for ice making. The amount of ice that can be produced is 12 kg/day. Using typical value for the efficiency of evacuated tube collector of water heating system of 65%, the following coefficient of performances (COP’s) are obtained: 44% for adsorption refrigeration cycle, 73% for dual-purpose solar water heater, 9.1% for dualpurpose solar adsorption refrigeration and 82.1% for dual-purpose of both solar water heater and refrigerator.

This article presents the effects of air exchange rate (ACH) and air exchange effectiveness (AEE) on thermal comfort level of a naturally ventilated office room. The study was conducted in an office at UPM, Malaysia. Influence of ACH and AEE on thermal comfort has not been investigated and is, therefore, not well understood. The main objective of this research is to investigate and assess these influences through the variable windows-door opening arrangements. To determine the windows-door opening performance in terms of ventilation air flow rate, 14 opening configurations have been considered. Thermal comfort variables were measured at the same time when ACH and AEE were evaluated. Through these data, the thermal comfort Fanger's indices (Predicted Mean Vote (PMV) and Predicted Percentage Dissatisfied (PPD)), ACH and AEE were calculated. These results showed that for a naturally ventilated office room three linear regression equations of PMV versus ACH and three linear regression equations of PMV versus AEE can be derived.

Purpose: During the last 20 years, interest in the closed adsorption heat pump and refrigeration systems has increased steadily. In this paper, consideration is given to aspects of adsorption refrigeration in terms of existing materials used in adsorption refrigeration, heat transfer characteristics of materials, and cost of materials and manufacturing. Design/methodology/approach: The paper is a general review of adsorption refrigeration technology. Findings: In recent years several papers have been published in this area and many aspects of the system have been addressed. Much effort has been devoted to enhance materials properties. Originality/value: The paper provides information of value to those involved with heat pump and refrigeration systems technology.

The daily mean wind speed data for 5 locations in Jordan over a period of 9 years are collected and analyzed. Data are fitted to the Weibull distribution function. Weibull parameters are derived from the cumulative function of the observed data records (1989-1997), and used to calculate the mean wind speed and variance of the theoretical distribution. The goodness of representing the observed distribution with the Weibull distribution is determined using the Kolmogorov-Smirnov (K-S) test. At the 1% and 5% levels of confidence the observed data are well represented by the Weibull distribution. The annual mean values of the wind speed of the observed and theoretical distributions are 6.10ms-1 and 6.26ms-1 for Ras.Monief, 4.79ms-1 and 4.77ms-1 for Aqaba, 3.07ms-1 and 3.15ms-1 for Amman and 3.09ms-1 and 3.13ms-1 for Irbid and 2.34ms-1 and 2.40ms-1 for Der Alla respectively. Based on the annual wind speed, wind resource forRas.Monief, Aqaba, Amman, Irbid and Der Alla are varied from very good to poor. The annual mean power density of Ras.Monief, Aqaba, Amman, Irbid and Der Alla are 261.76 Wm-2, 118.95 Wm-2, 57.45 Wm-2, 40.95 Wm-2, and 24.97 Wm-2 respectively. Values of the power density obtained from the manufacturer’s power distribution curve of a 300MW wind turbine at a hub height of 10 meters are also given for comparison. The result of the analysis showed that only Ras.Monief and Aqaba have good wind energy potential.

Single purpose solar water heating system has been commercialized and is now widely accepted. Effort has also been made to commercialize the single-purpose intermittent solar adsorption refrigeration system, but has not been well received. The combined system for water heating and refrigeration is still in the research stage. A proposed design and performance of a hybrid continuous solar adsorption system for water heating and refrigeration is described. The system comprises conventional solar flat plate collectors, a hybrid solar flat collector containing an adsorber for refrigeration and heat recovery, an adsorber bed heat exchanger, a storage tank (container) for heating and cooling of the adsorber bed, a hot water storage tank partition, a storage tank for condenser heat exchanger, a condenser, a receiver and an evaporator. In this design solar refrigeration is realized using activated carbon as adsorbent and methanol as adsorbate. When the absorbent is cooled the adsorbate in the receiver, which passes through the evaporator converts water in the evaporator into ice. For intermittent solar adsorption this process takes place at night. The use of the adsorbent in the hybrid collector and another in the adsorber bed helps maintain a continuous refrigeration cycle. The heat rejected by the adsorber beds and condenser is recovered and used to heat water for the purpose of domestic consumption. In a continuous 24-hour cycle, 16.86MJ/day of heat can be recovered from the adsorber beds and 5.3MJ/day from the condenser. In the single-purpose intermittent solar adsorption system, this heat is however wasted. The total energy input to the dual-purpose system during 24-hour operation is 61.2MJ/day and the total energy output is 50MJ/day. The latter is made up of 44.69MJ/day for hot water heating and 5.3MJ/day for ice making. The amount of ice that can be produced is 12kg/day. Based on a typical value of 0.65 for the coefficient of performance (COP) of a single purpose sol

Solar adsorption refrigeration is mainly realized using activated carbon as adsorbent and methanol as adsorbate. The study tested adsorption characteristics of three types of Malaysian activated carbons (AC-4060, AC-5060, AC-6070) with methanol by fitting Dubinin equation to the characteristic curve of the activated carbons and thus determine the available porosity. The P-T - X chart (pressure, temperature, and concentration) for each of the activated carbons was developed and the heat of adsorption was determined. A performance comparison of the activated carbons with methanol as the refrigerant for ice making was analyzed and the possibility of using the Malaysian activated carbon as adsorbent for adsorption refrigeration system was found satisfactory.For solar intermittent adsorption system, refrigeration process takes place at night. The use of the two adsorber beds working out of phase helps maintain a continuous refrigeration cycle. Efforts have been made to commercialize the single-purpose solar adsorption refrigeration system, but has not been well received. The dual-purpose solar continuous adsorption system for domestic refrigeration and hot water is the result of a series of researches done in the field of single-purpose of solar adsorption system for refrigeration with respect to the practical needs of industries and customers. A novel design and performance of a dual-purpose solar continuous adsorption system for domestic refrigeration and hot water is described. The system comprises of evacuated tube collectors, a water storage tank of two partitions each partition contains adsorber bed and condenser heat exchanger, a receiver, an evaporator, and ice box. Further more, the heat rejected by the adsorber beds and condensers during cooling process of refrigeration subsystem was recovered and used to heat water for the purpose of domestic consumption. In a continuous 24-hour cycle, 16.86 MJIday of heat can be recovered for heating of water storage tanks. I

Jordan is a developing country with limited natural resources. It imports most of its energy for heating, electric power generation, and other uses. The limited energy sources consider renewable energy options such as solar, wind, and hydropower as alternatives. For successful energy research and applications, weather parameters (wind speed, sunshine duration, humidity_ temperature, and global solar radiation) should be modeled. For solar energy applications, information on global solar radiation are required for the country over a long period of time. Some sites have no records of solar radiation data. So, developing methods to predict solar radiation from any available weather data are necessary. Models based on Angstrom formula using data such as Sunshine, Temperature and Humidity of four stations are described. Wind is an important energy resource and man has long sought to harness it. The calculation of the output of a wind machine requires knowledge of the distribution of the wind speed. Weibull distribution was applied to fit the probability distribution nature of wind speed. For all locations the wind speed data can be modeled easily by the Weibull distribution. Time series analyses of the weather parameters such as wind speed, relative sunshine duration, relative humidity, range in temperature extrenies, and relative solar radiation all as daily average were carried out. To apply AutoRegressive process, transformation technique (Differencing) was applied to generate stationary time series. Seasonal and non-seasonal AutoRegressive models of order p AR(P) were used to describe the weather parameters data for all stations.