Assessment of the Potential Use of Shallow Geothermal Energy Source for Air Heating and Cooling in the Kingdom of Saudi Arabia

A large part of the total energy consumption in buildings in the Kingdom of Saudi Arabia (K.S.A.), is devoted to air cooling. This leads to high electricity costs for residents and a high amount of equivalent CO2 emissions. The work presented in this paper aims at evaluating and applying shallow geothermal energy for cooling and heating to reduce cost and environmental issues in the Kingdom. The system is based on the earth-air heat exchanger (EAHE) equipped with an air circulation fan. In this study, six cities have been selected; Madinah city, where our university is located, and five other cities representing five different climatic zones. A new parameter called “geothermal percentage” is proposed to calculate the ratio of geothermal energy to the cooling/heating total load. It has been shown that the proposed system covers part of the cooling load and the total heating needs for almost all the country’s territory. However, both heating and cooling needs can be fulfilled by the EAHE for few cities such as Guriiat and Khamis, characterized by a moderate climate.

Hierarchical Optimization Model Based on V2G Technology

Large-scale electric vehicle (EV) random access to the power grid, the load peak-valley difference will become larger, seriously affect the stable operation of the power grid. In this paper, a V2G based bi-level optimal scheduling model for EV charging and discharging is proposed. The upper model takes the minimum variance of the total load as the objective function, and the lower model takes the increase of user participation and the maximization of user revenue as the objective function. The multi-population genetic algorithm is used to analyze the model, and the results show that the model can not only smooth the load fluctuation, effectively reduce the load peak-valley difference, but also maximize the economic benefits of users participating in V2G service.

PM₁₀ variation, composition, and source analysis in Tuscany (Italy) following the COVID-19 lockdown restrictions

To control the spread of COVID-19, in March 2020 exceptional restrictive measures were taken imposing a radical change in the lifestyle of millions of citizens around the world, albeit for a short period of time. The national lockdown, which in Italy lasted from 10 March to 18 May 2020, was a unique opportunity to observe the variation in air quality in urban environments in a condition of almost total traffic block and a strong reduction in work activities. In this paper, the data from seventeen urban monitoring sites in Tuscany are presented by comparing PM and NO2 of the two months before the start of the lockdown and the two after with the corresponding months of the previous three years. The results show that the total load of PM2.5 and PM10 decreased but it did not exhibit significant changes compared to previous years, while NO2 undergoes a drastic reduction. For three of these sites, the chemical composition of the collected samples was measured by thermo-optical, ion chromatography and PIXE analysis, and the application of multivariate PMF analysis allowed the PM10 source identification and apportionment. Thanks to these analyses it was possible to explain the low sensitiveness of PM10 to the lockdown effects as due to different, sometimes opposite, behaviors of the different sources that contribute to PM. The results clearly indicated a decline in pollution levels related to urban traffic and an increase in the concentration of sulfate for all sites during the lockdown period.

Design Technique for Load-Sharing and Monitoring of a Power Plant Using an Intelligent Control Technique

The application of Data Technology (IT) has been growing rapidly recently. IT utilized to monitor flowing power and distributing electrical energy which is produced by thermal power plant. This project explains how to build and design interface system. Electrical energy needs to be monitored in order to keep energy following. Single Board Computer (SBC), microcontroller, sensors, and transceivers are used in logging electrical power for this project. Following to the reliable need of an efficient power supply and the concern about poor electricity power supply, deregulation, consistent overload on already existing overstressed power supply system which has become a major concern to the social economic needs. The study case system generating capacity consist of 10 units of 2000KVA (20,000VA) = 16000W for power factor of 0.8 which is tied to the exiting load demand of 30MW capacity. Research identity mischarge between the generating capacity and the load demand requirement. That the generator can only a total load capacity of 15MW at one engagement on rationalization and subsequently take the next 15MW capacity to the generator supply. This sequence of operation has put the study zone into regular percentage (blackout) there by negatively affecting the economy activities of the area. This research work has proposed for an additional capacity of 2000 KVA (20 MVA =16 MW) generating power plant for a giving power factor of 0.8 on the view to notice the existing total load of 30MW without any form of rationalization and percentage (blackout) in order to improve the power quality and voltage profile without problem in the day-to-day occurrence activities. The concern for poor power grid supply in the study case (Bertoua community) for the given load of about 16M capacity are taken due consideration with 2MWW capacity thermal power plant on the view to propose solution to improve the quality of energy supply to the Bertoua community and environ. The system is designed with electronic circuitry that can be used to sense/monitor voltage, current, frequency, temperature, pressure and cool level. The design system is modeled in proteus and matrix laboratory (MATLAB) Environment with the application of isochronous mode of control with (10 unit of 2000kVA thermal plant. The improved mode of control (Isochronous technique) was preferred over droop type of generator load sharing techniques, because the improved versus allows and maintained constants speed and frequency regardless of gradual building up of the load to the peak demand scenarios. The modeled Simulink block are configured as an intelligent system multiple generators set in parallel state to monitor and control the gradual load increase from consumer-end to the generators capacity of 2mVA thermal power plant in order to allow load of 1×2000kVA, 2×2000kVA, 3×2000kVA, 4×2000kVA, 5×2000kVA, 6×2000kVA, 7×2000kVA, 8×2000kVA, 9×2000kVA, 10×2000kVA. Since the control system will become an essential factor for reliability of power plants and electrical distribution networks consumption and electric utility at large on the view to investigate appropriate load sharing and balancing, load scheduling, load forecasting, fuel-consumption pattern, optimizing generation capacity in order to optimize energy saving, costsaving and performance. Keywords: Load-Sharing, Monitoring

A field study on the load sharing behavior of a micropiled-raft underpinned by a waveform micropile

A waveform microiple(WMP) uses jet grouting method to generate shear keys along the pile shaft for improving the shaft resistance and cost efficiency. In this study,field loading tests were performed in this study to characterize the load sharing behavior upon inclusion of a waveform micropile (WMP) in a group of four micropiled-raft. First, single-pile compressive loading tests were conducted on three WMPs and five Type A micropiles (MP). Subsequently, a group-pile loading test was performed on a piled raft comprising 2 × 2 MPs and a central WMP. The load–settlements, axial stiffnesses, and load transfer mechanisms of individual MPs were analyzed during the tests, including the short- and long-term effects of the axial stiffnesses of the MPs on the load sharing ratio of the micropiled-raft. The single-pile loading test results revealed that the shear keys along the WMPs caused its bearing capacities and axial stiffnesses to be 1.5 times and 2–5 times higher than those of MPs, respectively. In the micropiled-raft loading test, the load sharing ratios of the MPs increased with their axial stiffnesses, and the highest load sharing capacity was exhibited by the WMP, which constituted 30% of the total load and 2–3 times that of MPs. Moreover, the influence of raft on the load-sharing capacity should be considered as well.

X-ray Diffraction Analysis to Explore Molecular Traces of Eccentric Contraction on Rat Skeletal Muscle Parallelly Evaluated with Signal Protein Phosphorylation Levels

We performed X-ray diffraction analyses on rat plantaris muscle to determine if there are strain-specific structural changes at the molecular level after eccentric contraction (ECC). ECC was elicited in situ by supramaximal electrical stimulation through the tibial nerve. One hour after a series of ECC sessions, the structural changes that remained in the sarcomere were evaluated using X-ray diffraction. Proteins involved in cell signaling pathways in the muscle were also examined. ECC elicited by 100, 75, and 50 Hz stimulation respectively developed peak tension of 1.34, 1.12 and 0.79 times the isometric maximal tetanus tension. The series of ECC sessions phosphorylated the forkhead box O proteins (FoxO) in a tension-time integral-dependent manner, as well as phosphorylated the mitogen-activated protein kinases (MAPK) and a protein in the mammalian target of rapamycin (mTOR) pathway in a maximal tension dependent manner. Compared to isometric contractions, ECC was more efficient in phosphorylating the signaling proteins. X-ray diffraction revealed that the myofilament lattice was preserved even after intense ECC stimulation at 100 Hz. Additionally, ECC < 75 Hz preserved the molecular alignment of myoproteins along the myofilaments, while 75-Hz stimulation induced a slight but significant decrease in the intensity of meridional troponin reflection at 1/38 nm−1, and of myosin reflection at 1/14.4 nm−1. These two reflections demonstrated no appreciable decrease with triple repetitions of the standard series of ECC sessions at 50 Hz, suggesting that the intensity decrease depended on the instantaneous maximal tension development rather than the total load of contraction, and was more likely linked with the phosphorylation of MAPK and mTOR signaling proteins.

Techno-Economic Analysis for Fertilizer House Using Hybrid Power Stations

Renewable energy sources are not necessarily declining carbon sources. A hybrid generation network may be used in the power market to maximize the usage of renewable energy sources. The aim is to model hybrid power station and to determine the most effective system design through cost estimation. The power consumption of an agricultural device illustrates fertilizer house electricity needs and agricultural land irrigated pumps providing an average of 165.44 kWh / h of electricity per hour, an overall energy use of 7.12 kW and a total load of operation of 19.57 kW. The standard radiation intensity is 5.35 kWh per m2 per day, the luminosity amount is an around 0.534, and the maximum wind velocity is 4.60 m/s. Electricity generation is $323,659.25 and the gross electricity expense (Co2) is $1,325 and reflects an annual monthly power consumption of 21,264 kWh (47.1 %) and 12,756 kWh/yr (36.8 %).

Assessment of Selected Models for FRP-Retrofitted URM Walls under In-Plane Loads

One way to improve a structure’s total load-bearing capacity during an earthquake is to apply fiber-reinforced polymers (FRP) to unreinforced walls. The study discusses the use of FRP to strengthen unreinforced masonry (URM) structures. Although, many studies were conducted on the FRP strengthening of URM buildings, most of them were experiments to investigate the success of retrofitting approaches, rather than developing a successful design model. A database of 120 FRP-reinforced wall samples was created based on the current literature. Various approaches for calculating the bearing capacity of FRP-reinforced masonry are presented and detailed. The findings of the experiments, which were compiled into a database, were compared to those derived using formulas from the literature and/or building codes, and the model’s limitations are discussed.

Safety Design in Electrical Design of High-rise Building in Low Voltage Distribution System

With the continuous improvement of intelligent and automatic level of electrical system in high-rise buildings, the structure of electrical equipment in high-rise buildings is becoming more and more complex, and the total load is also increasing. Higher requirements are put forward for the safety design of its power distribution system. The safety design of low-voltage power distribution system is more and more important for the reliability and safety of the electrical system in high-rise buildings. Based on this, this paper first introduces the high-rise building power transformation and distribution system, including the reliability analysis of high-rise building power distribution system, power supply solutions, etc. Secondly, it analyses the design of low-voltage distribution system in the electrical design of high-rise buildings, and finally studies the safety optimization of low-voltage distribution system in the electrical design of high-rise buildings.