Street lighting is one of the sectors where off-grid energy systems are used, and in the past decade interest in these systems has increased due to recent developments occurred both in LED and PV ...technology. This paper presents a techno-economic analysis of off-grid PV LED road lighting systems for northern, central and southern regions of Turkey. Road lighting calculations are conducted using DIALux software for M4 and M5 road lighting classes to obtain optimal LED luminaires, pole sizes, and spacings. Among the obtained LED powers, load profiles are created using real lighting hours of operation of the selected regions. And then, the required PV-battery systems are optimized using HOMER software. Finally, sensitivity analysis is performed for future projections considering possible increases in electricity prices and decreases in component cost of the PV systems. The results showed that the levelized COE of the off-grid PV LED road lighting systems vary between 0.229 and 0.362 $/kWh for M4, and 0.254–0.359 $/kWh for M5 road lighting class, depending on the solar potential of the region. And, the total NPC of the entire lighting installation per km vary between 24296 and 29123 $ for M5, and 33225–44318 $ for M4 road lighting class. According to the results, the systems are infeasible under current conditions in Turkey. Nonetheless, they have the added benefits of contributing to the reduction of CO2 emissions. Moreover, future projections show that the systems can be feasible if the declining trend in PV system costs continues and electricity prices increase.
•Techno-economic analysis of off-grid PV LED road lighting systems were performed.•Road lighting calculations are made using DIALux software.•HOMER software is used for PV-battery size optimization.•Projections are made for increasing electricity prices and decreasing PV costs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The most common sources of error in the preanalytical phase are considered to be at the stage of patient preparation and sample collection. In order to reduce the preanalytical errors, we aimed to ...determine the level of phlebotomists knowledge about the preanalytic phase before and after planned trainings in the study.
Training about preanalytical processes was given to the 454 health professionals and the majority of them were employed as nurse. Questionnaires before and after training were conducted. In order to assess the effect of the training into the process, preanalytical error rates were calculated before and after training.
The total correct answer rates of vocational school of health diplomaed were statistically lower than the total correct answer rates of other. It was observed significantly increase in the rate of correct answers to questionnaire and significantly decrease in preanalytical error rates after training.
The results of the survey showed that the attitudes of the phlebotomists were diverse in the preanalytical processes according to the levels of education and their practices. By providing training to all staff on a regular basis, their information about preanalytical phase could be updated and hence, it may possible to significantly reduce the preanalytical errors in health practice and nursing science.
•Optimal PV-BESS sizing considering HEMS-based demand response and self-consumption.•The optimal configuration is 3 kW PV – no BESS – 10° tilt angle in Istanbul.•BESS use becomes viable in Istanbul ...with −25% battery or +25% electricity prices.•The NPV of PV-BESS units increases significantly with the use of HEMS.•The optimal PV-BESS capacity for HEMS use is determined in southern EU countries.
Today, selling electricity to the grid has lost its former profitability with reduced feed-in tariff (FiT) rates. This makes it crucial for prosumers to increase self-consumption and size their photovoltaic (PV) and battery energy storage system (BESS) units accordingly. Self-consumption can be increased through demand-side management (DSM) and an efficient DSM can be achieved using home energy management systems (HEMSs). Therefore, as its main contribution, this study proposes an optimal PV-BESS sizing model for HEMS-equipped prosumers considering day-ahead load scheduling-based DSM. Unlike other studies in the literature, the proposed model takes into account the determination of optimal PV tilt angle, load scheduling of all types of controllable appliances (time-shiftable, thermostatically controllable, power-shiftable), consideration of battery degradation, and vehicle-to-home (V2H) availability in the sizing procedure. First, the mixed-integer linear programming (MILP)-based model performs demand response (DR) and increased self-consumption to minimize the daily bill. Second, it simulates one year of HEMS operation and determines the net present value (NPV) of a PV-BESS configuration over the system lifetime. Finally, it repeats the same process for each combination of PV capacity-PV tilt angle-battery number and chooses the combination with the highest NPV as the optimal design.
The simulations were conducted to find the required PV-BESS capacity for a HEMS-equipped household with average daily electricity consumption of 37.5 kWh in Istanbul, Turkey. The optimal configuration was found to be 3 kW PV without BESS at the tilt angle of 10°. A techno-economic sizing comparison was made between households using and not using HEMS. The NPV of PV-BESS was found to be significantly higher with HEMS use ($2273) compared with that without HEMS use ($920). Lastly, a sensitivity analysis was performed based on rising electricity prices (+25%, +50%, +75%, +100%) and declining battery prices (−25%). The use of BESS became viable in Turkey even with +25% electricity prices or −25% battery prices.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Turkey attaches great importance to energy diversification to reduce the energy dependence on fossil resources. In this regard, Turkey assigned energy targets by 2023 including 20 GW of installed ...wind capacity. Yet, despite the good efforts, the current wind installed capacity of 8 GW is far behind the assigned target. This study presents a comprehensive review of wind energy status in Turkey focusing on policies and incentives for improvement of wind energy progress in the country. To that end, the global wind energy market is evaluated and a set of recommendations is presented in the context of the importance of local employment and establishment of local wind energy industry. Then, a feasibility analysis is performed to discuss the current feed-in tariff scheme in Turkey. Lastly, Turkey’s competitive position is evaluated over a SWOT analysis to give an overview of all positive and negative determinants, considering internal and external factors.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this paper, we study ⊕-sb-metric spaces, which were introduced to generalize the concept of strong b-metric spaces. In particular, we study the properties of the topology induced via an ⊕-sb ...metric (separation properties, countability axioms, etc.), prove the continuity of the ⊕-sb-metric, establish the metrizability of the ⊕-sb-metric spaces of countable weight, discuss the convergence structure of an ⊕-sb-metric space and prove the Baire category type theorem for such spaces. Most of the results obtained here are new already for strong b-metric spaces, i.e., in the case where an arithmetic sum “+” is taken in the role of ⊕.
Solar radiation falling on photovoltaic (PV) panel surface can be maximized via solar tracking systems, however, in return for infeasible investments. On the other hand, manual and periodic tilt ...adjustment of PVs can increase energy yield significantly and cost-effectively. Therefore, this study presents a techno-economic analysis of 1 MW PV power plants with manually adjustable tilt mechanisms. Firstly, the optimal tilt angles for fixed and periodically adjusted (monthly, seasonal, and semi-annual) PV systems in locations with different solar characteristics in Turkey are estimated, and then an economic analysis is performed, including a sensitivity analysis. The results show that, manual tilt adjustment provides a remarkable net present value (NPV) increase in Turkey between 12.4 and 14.9% compared to fixed-tilt. The discounted payback period (DPBP) ranges between 9.20 and 12.36 years and can be shortened by 8–10 months. The internal rate of return (IRR) of 5.4–8.6% can be increased by 0.7–0.9%.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Background: Environmental tobacco smoke (ETS) in the home continues to be a major health risk for children around the world. Measuring ETS is a central feature of clinical and epidemiological ...studies, with children’s exposure often assessed through parental estimates. The authors examined the relationship between parent‐reported estimates of children’s exposure to ETS and children’s urinary cotinine levels and evaluated the ETS exposure and its effect on respiratory health in children.
Methods: A total of 188 school children were included in the study. Parents were asked to complete a questionnaire about their smoking habits, their children’s respiratory morbidity status and housing conditions. Urinary cotinine levels were measured in children.
Results: According to the responses, 72.3% of the children came from households with smokers, and 34.6% had daily exposure to ETS. When urine cotinine levels of >10 ng/mL were used as the yardstick of exposure, 76% of the children were identified as ETS exposed. No relation was detected between the symptoms of respiratory tract diseases and ETS exposure. To determine the amount of ETS exposure, the contribution of parental reports was low.
Conclusion: To evaluate the level of ETS exposure of children, the parents’ reports were not reliable. The addition of a biological measure results in a more informative estimate of ETS exposure in children.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Various types of markers have been used so far in order to reveal myocardial perfusion defect. However, these markers usually appear in the necrosis phase or in the late stage. Having been the focus ...of various investigations recently, ischemia-modified albumin (IMA) is helpful in establishing diagnosis in the early stages of ischemia, before necrosis develops.
30 patients that underwent only coronary bypass surgery due to ischemic heart disease within a specific period of time have been included in the study. IMA levels were studied in the preoperative, intraoperative, and postoperative periods. The albumin cobalt binding assay was used for IMA determination. Hemodynamic parameters (atrial fibrillation, the need for inotropic support, ventricular arrhythmia) of the patients in the postoperative stage were evaluated. Intraoperative measurement values (mean ± SD) of IMA (0.67677 ± 0.09985) were statistically significantly higher than those in the preoperative (0.81516 ± 0.08894) and postoperative (0.70477 ± 0.07523) measurements. Considering atrial fibrillation and need for inotropics, a parallelism was detected with the levels of IMA.
IMA is an early-rising marker of cardiac ischemia and enables providing a direction for the treatment at early phases.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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