Advanced Energy Technologies
Abraham Olatide Amole; Adebimpe Oluwaseun Adeyeye; Daniel Oluwaseun Akinyele; Kehinde Adeleye Makinde; Stephen Oladipo
Abstract
The use of Diesel Generators (DGs) and gas turbines to power oil rigs is characterized by pollution due to the emission of harmful gases like carbon dioxide, very high noise levels, high maintenance costs, and the inability to start the platform if the DG fails. Offshore wind energy generation system ...
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The use of Diesel Generators (DGs) and gas turbines to power oil rigs is characterized by pollution due to the emission of harmful gases like carbon dioxide, very high noise levels, high maintenance costs, and the inability to start the platform if the DG fails. Offshore wind energy generation system provides a viable alternative means of powering the oil rig and can also be integrated to operate in parallel with gas turbines. However, offshore wind energy might fail if not properly designed due to the high variability of wind resources. Hence, the objective of this work is to design offshore Wind Turbine Generator (WTG) energy generation system, DG, and hybrid DG-WTG for the black start of an offshore oil rig. The designed energy systems are simulated using HOMER Pro. Furthermore, the performance of the simulated systems was evaluated using the electrical production, unmet load, and emission profile as the performance metrics. The results of the hybrid DG-WTG powered black start revealed that 150kW DG generated 322,071kWh/yr representing 6.77% of the total generation and 1.5MW WTG generated 4,434,632kWh/yr representing 93.2% of the total generation. The comparison of the emissions from DG and DG-WTG revealed that 294,058kg/yr, 1,945kg/yr, 80.9kg/yr, 9.02kg/yr, 720kg/yr, and 688kg/yr of CO2, CO, UH, PM, SO2, and NO, respectively, were released into the atmosphere by DG-WTG which is very low compared to 969,129kg/yr, 6,109kg/yr, 267kg/yr, 37kg/yr, 2373kg/yr, and 5739kg/yr of CO2, CO, UH, PM, SO2, and NO, respectively, released into the atmosphere by DG. The sensitivity analysis revealed that while the electrical production of 100kW and 50kW DGs decreased with an increase in WTG height, the electrical production of 1.5MW WTG increased with an increase in WTG height. It was further revealed that the higher the WTG height the smaller the quantity of the emission released into the atmosphere.
Advanced Energy Technologies
Zeinab Sabzian-Molaee; Esmaeel Rokrok; Meysam Doostizadeh
Abstract
In this study, a novel stochastic planning method is proposed for AC-DC hybrid distribution networks. The proposed approach is based on the graph theory, and the optimal AC-DC structure of the network is selected among the system spanning trees. The presented method is a Mixed Integer Nonlinear Programming ...
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In this study, a novel stochastic planning method is proposed for AC-DC hybrid distribution networks. The proposed approach is based on the graph theory, and the optimal AC-DC structure of the network is selected among the system spanning trees. The presented method is a Mixed Integer Nonlinear Programming (MINLP) problem, which is solved using genetic algorithm. The buses and lines of the network can be either AC or DC to minimize the system investment costs in the master optimization problem. The location and capacity of the Distributed Energy Resources (DERs) as well as the site and size of the Electric Vehicle (EV) charging stations are optimized in the slave problem to minimize the network losses and system costs. The proposed model utilizes Monte Carlo simulation to deal with the stochastic variations of the renewable energy resources power and load demands. Besides, the converter efficiency curve in the proposed planning problem is modeled based on a function of its input current using PLECS software. The proposed approach for network design can be applied to different DG resources and AC-DC loads. The comparison between the simulation results of the proposed approach and the conventional AC planning method demonstrates the efficiency of the proposed model in reducing network losses and system costs
Advanced Energy Technologies
Iraj Mirzaee; Aref Razmjoo; Nader Pourmahmoud
Abstract
This study conducts thermodynamic analysis on three trigeneration cycles including Organic Rankine Cycle (ORC), Liquefied Natural Gas (LNG) cold energy, and absorption refrigeration cycle in order to select appropriate working fluids. Different types of ORC cycles including simple ORC, regenerative, ...
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This study conducts thermodynamic analysis on three trigeneration cycles including Organic Rankine Cycle (ORC), Liquefied Natural Gas (LNG) cold energy, and absorption refrigeration cycle in order to select appropriate working fluids. Different types of ORC cycles including simple ORC, regenerative, and ORC with Internal Heat Exchange (IHE) were investigated. For those types, the operation of six working fluids with different thermodynamic behaviors (R141b, R124, R236fa, R245fa, R600, and R123) was evaluated. In power plants, a low-grade heat source was provided by condensing boiler hot water energy while the thermal sink was prepared by cold energy of LNG. The effect of boiler temperature variation on energy and exergy efficiencies was investigated. According to the derived results, regenerative ORC-based systems possessed maximum energy and exergy efficiencies, while simple ORC and ORC with internal heat exchanger exhibited approximately the same quantities. Also, among these analyzed working fluids, R141b had the maximum energetic and exergetic efficiencies, while R124 and R236fa had minimum performance.
Advanced Energy Technologies
Sibel Dursun; Ercan Aykut; Bahtiyar Dursun
Abstract
Somalia–Turkish Training and Research Hospital in Mogadishu, is only powered by diesel generator currently. In this paper, the energy demand of this hospital is utilized by determining the optimum hybrid renewable energy generating system. By HOMER, a sensitivity analysis has been made with emphasis ...
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Somalia–Turkish Training and Research Hospital in Mogadishu, is only powered by diesel generator currently. In this paper, the energy demand of this hospital is utilized by determining the optimum hybrid renewable energy generating system. By HOMER, a sensitivity analysis has been made with emphasis on three significant variables such as average wind speed, present diesel price, and solar radiation. From the results, it can be said that an optimum system is the standalone wind-diesel-battery storage Hybrid Renewable Energy System (HRES) with the configuration of 1,000 kW wind turbine, 350 kW diesel generator, 250 kW power converters, and 300 batteries. Additionally, the net present cost of the optimum system is calculated to be $5,056,700 and its cost of energy is estimated to be 0.191 $/kWh. The present cost of energy for Somalia is 0.5 $/kWh. This shows that the energy cost for the proposed HRES is cheaper than the conventional one. Lastly, according to the results, it is clear that the wind–diesel–battery storage HRES seems more environment friendly than other HRESs.
Advanced Energy Technologies
Mahnoosh Eghtedari; Abbas Mahravan
Abstract
Increasing fossil fuel consumption in the building, especially in the air-conditioning sector, has increased environmental pollution and global warming. In this research, a zero-energy passive system was designed to ventilate the building and provide comfortable conditions for people in the summer. A ...
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Increasing fossil fuel consumption in the building, especially in the air-conditioning sector, has increased environmental pollution and global warming. In this research, a zero-energy passive system was designed to ventilate the building and provide comfortable conditions for people in the summer. A hybrid passive system was designed for indoor cooling to minimize fossil energy use. This research was done experimentally- and analytically and by simulation. An experimental study comprising a test chamber and simulation using Builder Design software was carried out to evaluate the cooling and ventilation potential of a hybrid passive system functioning. In the experimental section, air temperature, humidity, and airflow for the outdoor environment and the output of the evaporative cooling channel were measured. These measurements were tested in August from 9:00 AM to 3:00 PM for six consecutive days. The obtained experimental data were given to Design Builder software as an input parameter, and then, the comfort conditions inside the chamber, the dimensions, and location of the air inlet valve into the chamber were examined. The findings showed that the proposed system could reduce the air temperature by an average of 10 oC and increase the air humidity by 33 %. The findings showed that the air inside the chamber was comfortable during the hottest hours of the day. Raising the valve location, increasing the area, and increasing the volumetric flow rate of the air increased the percentage of dissatisfaction. The findings showed that in addition to wind speed and air temperature, the geometrical shape of the air inlet opening contributes to indoor air comfort conditions.