Original Article
Solar Thermal Engineering
Mahdi Rezaei Rad; Rouzbeh Shafaghat; Amirhossein Aghajani afghan; Behrad Alizadeh Kharkeshi
Abstract
This experimental study introduces a solar humidifier-dehumidifier desalination model as a type of open-air-open water (OAOW) system; also, a new condenser with thermoelectric modules is applied in the dehumidifier unit. The experimental tests were done by considering climate conditions in the north ...
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This experimental study introduces a solar humidifier-dehumidifier desalination model as a type of open-air-open water (OAOW) system; also, a new condenser with thermoelectric modules is applied in the dehumidifier unit. The experimental tests were done by considering climate conditions in the north of Iran (Mazandaran province, Babol), and the effect of the inlet air's temperature and flow rate on the system's functional characteristics and condenser was investigated to improve the performance. Sensors measured the data related to the fluid temperature and humidity of the cycle at different points; other data was also gathered by psychrometric chart and EES software. The results section investigates water generation rate, GOR, coefficient of performance (COP), and condenser efficiency. The results showed that the highest water production is 420 g/hr, and the highest GOR is 0.19. Also, the water production rate and COP increase as the inlet air temperature rises. At temperatures lower than 75o Celsius, due to the air saturation, the maximum point of the water production and COP occurs at a flow rate of 0.022 kg/s. at high temperatures, increasing the flow rate raises water production, and on the other hand, the COP in the condenser is 0.8 at the highest point. According to the economic analysis done for the proposed model, the freshwater cost is 0.098-0.049 $/year for one liter.
Original Article
Mojtaba Ghiyasi
Abstract
Data envelopment analysis (DEA) is a mathematical programming approach for the performance basement of the production units from a production economic view. In this paper, we analyze the performance of Iranian wind power plants (IWPP) using DEA. In the second phase of the study, we utilize the inverse ...
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Data envelopment analysis (DEA) is a mathematical programming approach for the performance basement of the production units from a production economic view. In this paper, we analyze the performance of Iranian wind power plants (IWPP) using DEA. In the second phase of the study, we utilize the inverse DEA approach as a valuable method for the future planning of the IWPPs. In this step, we considered five different scenarios from a short-run up to a long-run planning for electricity production by renewable energy. In the short-run we just need more capacity factor rather than capital. Although in the mid-run we did not presume capital extension, the result suggested this. In the end, in the long-run planning extension in not only capacity factor but also more investment in the higher technologies is a requirement for reaching the desired electricity production.
Original Article
Tide, Wave and Hydro Power
Hosein Jokar; Abuzar Abazari; Reza Dorostkar
Abstract
One of the main needs for dhow vessels is fuel for diesel generators that generate electricity, which in turn is used in refrigerators and electronic devices. Concerning the development of new devices for electricity generation such as point absorber wave energy converters, in the present research for ...
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One of the main needs for dhow vessels is fuel for diesel generators that generate electricity, which in turn is used in refrigerators and electronic devices. Concerning the development of new devices for electricity generation such as point absorber wave energy converters, in the present research for the first time, the feasibility of installing such converters on the hull of the dhow vessel and their performance is being examined. These WECs expanded on the sea-free surface level during anchoring time. Depending on the relative angular displacement between the WEC and the dhow hull the electricity is produced. In the present study, the simulations are done based on the diffraction theory in Ansys AQWA. The results showed that for considering four installed WECs, the maximum output power of 400 kilowatts is produced, which is an acceptable amount of energy for supplying the common electronic devices on the dhow vessel. In addition to this, it has been shown that the hybrid system of the dhow and WECs in the anchoring mode has fewer dynamic responses compared to a single dhow without WECs. Such conditions can be utilized for the comfort of the passengers or special operations during the anchoring time. It was also observed that the buoy size does not have a considerable effect on the production power and dynamic response of the platform, while the length of 2 m for the lever and angle of 90 degrees of the incident wave is optimum from the production power point of view.