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Retrofitting heating, ventilation, and air conditioning (HVAC) systems in existing buildings and applying energy-efficient technologies can significantly reduce energy consumption and greenhouse gases emissions. In this work, two options of HVAC retrofitting were proposed and discussed for the existing heating system of school of engineering at the University of Jordan as a case study. The experimental tests showed that only one of the three diesel boilers work normally while the other two boilers are not efficient, with actual efficiency of 25%. The first retrofitting was to upgrade the existing heating system to a liquefied petroleum gas (LPG) boiler system with estimated annual saving of 29,757 Jordanian dinar (JOD), and a payback period of 3.9 years. The second option for retrofitting was a new HVAC system for the building including heating and air conditioning with a variable refrigerant flow (VRF) system and heat pump chiller. The estimated cost showed that the VRF system was the lowest one in running cost in winter. The diesel boilers had the highest greenhouse gas emissions with an average value of 377.3 tons of CO2 per year, while LPG boilers achieved the second highest emissions of around 279 tons of CO2 per year, whereas the heat pump chiller in winter produced 199 tons of CO2 and the VRF system emitted 180 tons in winter. The LCCA economic analysis was performed for the proposed systems, showing that the LPG boilers system was more feasible than the diesel boilers system, while the VRF system was more feasible than the heat pump chiller system.

In this work, a hybrid system consisting of a parabolic trough collector and a steam power plant is proposed. The effect of utilizing the parabolic trough collector on improving the performance of the plant and reducing fuel consumption has been studied experimentally. This study was implemented on a lab scale hybrid energy system consisting of a parabolic trough collector unit incorporated into a biomass-oil shale fired steam power plant during startup conditions. To determine the performance of this lab-scale hybrid system, the efficiency of the parabolic trough collector standalone system has been measured and the flow rate of the system has been tuned to 0.31 L/min to obtain an efficiency of 10.2%. The biomass-oil shale fired power plant worked with superheated steam at 377 °C temperature and 0.6 MPa pressure. The thermal efficiency of the power plant was 12.6% with net output power of 6.3 kW without using the parabolic trough collector unit. It was found that the performance of the hybrid system has shown better efficiency than the standalone biomass fired power plant with the same fuel mixture ratio and steam flowrate. The fuel mixture consumed in the hybrid system decreased by 62.0% at starting up condition. This result may be extended to steady-state operating conditions by increasing the number of parabolic trough collector units utilized. Furthermore, the overall thermal efficiency of the hybrid parabolic trough collector power plant system may reach 33.3% during steady-state operation if 48 parabolic trough collector similar units were used. These parabolic trough collector units should be arranged in three parallel rows, each row of 16 units in series.

In recent years, many researchers have attracted interest in wastewater treatment using activated carbon produced from cheap raw materials. In this work, an activated carbo-aluminosilicate (ACS) - supported zero-valent iron (ZVI) composite was produced from Um AL-Rasa oil shale mine and examined to eliminate Chromium (VI) from contaminated water. Activation of raw oil shale fine particles ( < 212 μm) was chemically performed using 95 and 5% wt of H2SO4 and HNO3, respectively, as activating agents. The activated material was further treated with caustic soda, named ACS, and modified with fine zero-valent iron particles < 212 μm), called ZVI/ACS composite. Kaolin was added to the composite with the ratio: (50 % wt. light kaolin: 50 % wt. ACS), named as ZVI/ACS/K. The XRD analysis for both composites confirmed iron dispersion at 45°. Adsorption experiments were carried out using the two adsorbents ZVI/ACS & ZVI/ACS/K under different values of pH, and adsorbent dosage. The results indicated that the reduction of Chromium was maximum under the 3 pH value and 2.0 gm amount of ZVI/ACS/K. Furthermore, it was found the removal rate was eenhanced by 17% and 24.7% when ZVI/ACS & ZVI/ACS/K adsorbents were used respectively compared to that when only ACS adsorbent was used alone. Finally, The dependency of Chromium removal on its initial concentration by ZVI/ACS/K adsorbent was also investigated at two different temperatures of 27℃ and 50℃. The results indicated a decrease in the removal rate of the Chromium as the concentration increased at 27℃ , however the removal rate previously enhanced at 50℃ at all initial concentrations.

Buildings, both residential and commercial, continue to be a major source of energy consumption in the world due to the escalating rate of global energy demand. Energy supplied to buildings through conventional means negatively impacts the environment. Due to its geographic location and climatic conditions, Jordan has a high solar energy potential. This encouraged using photovoltaic panels on building envelopes to produce electricity. One of the major problems facing this technology is the performance of the installed systems. In this context, this paper adapted the Theory of Inventive Problem Solving (also known as TRIZ) to improve the performance of photovoltaic systems; with less cost, less time, less installation place, and high output power. TRIZ principle was applied to a case study of an existing photovoltaic system in Jordan in order to study the impact of materials used in PV cells construction on a PV system's performance. The analysis of the results show the potential of increasing the energy produced by changing the material of the PV cells. Economic analysis was also carried out for the suggested PV systems.

This study produces a technical and economic analysis of a farm- fed biogas plant that utilizes cow manure to produce electricity and heat via combined heat and power unit. The electricity generated is directly injected into the grid while heat is used within the biogas plant. The biogas system design was done depending on number of cows in the farm, which denotes the amount of manure available as feedstock. The economic performance of the proposed biogas plant was evaluated using various economic indicators. The levelized cost of electricity and the avoided greenhouse gas emissions were calculated too. The preliminary design and economic feasibility results proved the profitability of the manure-based biogas systems on wide range of farm sizes. The net present values of a 100-cow, 500-cow, 1,000-cow, 1,500-cow and 2,000-cow farms were all positive. The internal rate of return values were 11%, 12%, 13%, 16% and 17%, respectively, and the levelized cost of electricity values were 0.071, 0.069, 0.064, 0.055 and 0.055 JOD/kWh, respectively. The study also produced a design for a centralized anaerobic digestion plant depending on Jordan resources. The government role in promoting biogas-based electricity was discussed too.

Unlike conventional fresh water producing systems, from saline or brackish water, the innovative solar water producing systems are efficient and effective. Experiments were conducted on two identical roof-type solar stills and simultaneously tested under the same weather conditions. One of these stills was modified by integrating a vacuum pump to lower the pressure inside while the other still was used as a reference unit. Different concentrations of Al2O3 nanoparticles were chosen, 0.2%, 0.4%, and 0.6%, and used with water inside the modified still. It was verified that the modified still, without nanoparticles, yields 34.84% more production than the conventional still. In addition, the modified still with a 0.4% of Al2O3 nanoparticles produced the highest percentage of distilled water, 44.42% in comparison to the one without the use of Al2O3 nanoparticles, followed by 37.94% and 24.07% for 0.6% and 0.2% of Al2O3 nanoparticles, respectively.

Predictive indices like the atherogenic index of plasma (AIP) have been developed to estimate the risk of cardiovascular disease (CVD). Metabolic surgery is the most effective treatment for a rapid improvement of morbid obesity and its comorbidities such as type 2 diabetes (T2D) and CVD. A decreased reoccurrence of CVD after metabolic surgery has been reported by several studies. However, studies utilizing predictive indices for CVD risk in CVD-free morbid-obese patients who undertook laparoscopic sleeve gastrectomy (LSG) are lacking. Here, we use AIP as a tool to evaluate the improvement in CVD risk post-LSG in morbid-obese people who had no history of CVD. Method. We compared baseline, 6- and 12-month post-LSG score of AIP, vascular age, circulating biochemical markers related to CVD in two groups of BMI and age-matched morbid-obese participants with and without T2D. Results. At baseline, people with T2D had significantly higher AIP both, with morbid obesity (0.23±0.06, p

A smart cooling system to control the ambient temperature of a premise in Amman, Jordan, is investigated and implemented. The premise holds 650 people and has 14 air conditioners with the cooling capacity ranging from 3 to 5 ton refrigerant (TR) each. The control of the cooling system includes implementing different electronics circuits that are used to sense the ambient temperature and humidity, count the number of people in the premise and then turn ON/OFF certain air conditioner(s). The data collected by different electronic circuits are fed wirelessly to a microcontroller, which decides which air conditioner will be turned ON/OFF, its location and its desired set cooling temperature. The cooling system is integrated with an on-grid solar photovoltaic energy system to minimize the operational cost of the overall cooling system.

Abstract In this paper, we study the effect of thermal fluctuations on the thermodynamics of a black geometry with hyperscaling violation. These thermal fluctuations in the thermodynamics of this system are produced from quantum corrections of geometry describing this system. We discuss the stability of this system using specific heat and the entire Hessian matrix of the free energy. We will analyze the effects of thermal fluctuations on the stability of this system. We also analyze the effects of thermal fluctuations on the criticality of the hyperscaling-violation background.

BACKGROUND: Despite the availability of several methods (invasive and noninvasive) for the diagnosis of Helicobacter pylori infection, no test is considered to be the ‘gold standard’. Endoscopy-based tests are regarded as the reference method in most studies.

Water transmission lines have potential reserved energy, which is usually lost. Therefore, targeting this clean energy to produce electricity to power up the auxiliaries and utilities of water plants or consumers is financially and environmentally beneficial. This paper aims to investigate the feasibility of installing an inline hydropower system in an existing transmission water pipe. It analyzes the feasibility of implementing a mini-hydropower plant in the transmission line of Liwa's reservoir in the UAE. The maximum possible power harvested is 218.175 kW at the given water flow rate and net head. The payback period and the return on investment are analyzed based on different scenarios related to capital investment, operation, maintenance cost, and plant capacity factor. It is found that the payback period ranges between one to six years, where the return on investment can be as high as 85%. Furthermore, the expected CO2 emissions saving for this project is calculated to be between 395 and 1939 tons per year. [ABSTRACT FROM AUTHOR]