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Given the concern for maintaining voltage stability in power systems integrated with renewable power systems due to a mismatch in generation and demand, there remains a need to invoke flexible alternating current transmission system (FACTS) devices in the distribution network. The present paper deals with identifying the locations of placement of a static var compensator in an experimental IEEE 14-bus system; the voltage drop in different buses in an IEEE 14-bus system is calculated by the standard formula. The total voltage drop in the network (TVDN) is also calculated as a reference. The ranking of buses in order of decreasing voltage drop is made, and the weak buses are identified as those showing the maximum or near-maximum voltage drop for the installation of a Static Var Compensator (SVC). The optimum usable size is calculated using a Genetic Algorithm approach to optimize the installation cost. After size optimization, installing a 2 MW solar generator is considered for the weak and most potential bus, which suffers from voltage drops or power loss. Based on the generator at the weakest bus, the total power loss in the network is calculated and compared with a similar method to assess the efficiency of the proposed model. Thus, the voltage stability enhancement problem is solved by applying a Genetic algorithm (GA) to optimize SVC size and using the Total Voltage Drop in Network (TVDN) method to identify weak buses in the systems. It is found that the performance of the proposed system is comparable with another existing system. It is further observed that a gain in power loss to 6.56% is achievable by adopting the proposed strategy, and the gain is better than the other system. [ABSTRACT FROM AUTHOR]

Because textile industries are intensely water-consuming and generate a huge quantity of wastewater, the present study examines the scope of using solar thermal technology to treat wastewater from textile industries. A hybrid technology, comprising a compound parabolic concentrator-based solar thermal system in conjunction with a Membrane Distillation (MD) system, is experimented with for wastewater treatment in textile industries. The MD system requires a water temperature of around 90 °C for efficient functioning. The advanced MD technology using waste heat combined with solar heat to meet the system's thermal load is technologically evaluated for an experimental textile industry in India. Moreover, the present study critically analyses the techno economics of the proposed hybrid technology. A detailed financial analysis has revealed that, besides technological superiority, the recommended technology is also financially rewarding for wastewater treatment in the textile industry. To cope with the delayed payback period, financial incentives are recommended so that the system becomes a lucrative technological option. [ABSTRACT FROM AUTHOR]

Nitrogen-doped Bernal graphene has several advantages, including improved electrical conductivity, enhanced stability and better compatibility with electrolytes. This article presents the synthesis of few-layer pristine graphene and nitrogen-doped Bernal graphene (CVDNG) through the Low-pressure chemical vapor deposition approach and its application for flexible supercapacitors. A novel hot lamination-assisted approach is employed to transfer the graphene on the desired substrates, enabling the reusability of copper. Raman mapping is utilized to analyze the characteristic bands and statistical distribution of Bernal stacking in CVDNG. The doping in graphene is confirmed through the X-ray photoelectron spectroscopy suggesting the content of pyrrolic-N (73.38%), pyridinic-N (20.28%) and graphitic-N (6.38%) in the CVDNG. Cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy are performed by sandwiching the polyvinyl alcohol-sodium perchlorate based hydrogel membrane between two symmetrical supercapacitor electrodes. CVDNG symmetrical supercapacitor device delivers an enhanced areal capacitance of 26.75 mF cm−2 with a high energy density of 2.14 mWh cm−2 with a power density of 72 mW cm−2 at 0.05 mA cm−2. The device shows excellent flexibility by retaining 91.1% of its capacitance at extreme bending (180° angle) conditions and excellent specific capacitance retention (90.6%) after 10,000 charge-discharge cycles. [Display omitted] • Nitrogen-doped Bernal graphene through the LPCVD approach for flexible supercapacitors. • A novel PMMA free approach to transfer the graphene, enabling the reusability of copper. • NaClO 4 -PVA based quasi-solid-state hydrogel membrane electrolyte. • The device shows excellent flexibility by retaining 91.1% of its capacitance at extreme bending (180° angle) conditions. • Excellent specific capacitance retention (90.6%) after 10,000 charge-discharge cycles. [ABSTRACT FROM AUTHOR]

This paper analyzes the potential of solar thermal systems for being employed for process heating in cotton-based textile industries. The technological capability of a flat plate collector (FPC) to meet the solar industrial process heating (SIPH) requirement in yarn production is assessed. Moreover, the usability of a parabolic trough collector (PTC) in meeting the technological mandates of SIPH in fabric processing units is critically examined. Further, this paper reports the findings of a study on the potential cost advantage of solar process heating over the conventional process heating practices in cotton-based textile industries. The approach involves the selection of the locations of sample textile industries and the employable solar collector technologies, as well as assessment of financial reward, if any. Eight different cotton-based textile industries located in different geographical domains (in India) are selected. The selected textile industries are situated within the textile hubs existing in different states across India. Analysis of technoeconomic benefit derivable in selected textile industries using FPC for hot water generation and PTC for steam generation is presented. In the case of FPC-based SIPH systems, the maximum value of solar fraction is estimated to be 0.30 and the corresponding estimation for the levelized cost of useful thermal energy (LCUTE) delivered comes out as INR 790/GJ to INR 1020/GJ. On the other hand, in case of parabolic-trough-solar-concentrator-based SIPH systems, LCUTE is estimated in the range of INR 1030/GJ to INR 1610/GJ. From a critical analysis of financial viability in consideration of related factors such as payback time and return on investment in SIPH, it appears that the SIPH systems for hot water generation may be a good choice, whereas SIPH systems for steam generation are seen to have longer payback periods and lower returns on investment, and, therefore, it seems that adequate financial support from central and state governments with additional supports from bilateral or multilateral organizations may enable them to become a sustainable technology option. [ABSTRACT FROM AUTHOR]

Resistance to early blight in the tomato was assessed by examining various parameters of the progress of the disease. Artificial inoculation and the scoring technique were standardized. Test plants were inoculated with 125 cfu/ml of a 12-day-old culture of a pathogenic isolate of Alternaria solani. Screening under artificial conditions was more informative than that under natural epidemic conditions. Tomato cultivars CLN-2071-C, CLN-2070-A, BSS-174, and DTH-7 with resistance expressed as slow blighting against four pathogenic isolates of A. solani, were selected for cultivation in disease-prone areas. Disease intensity increased with the age of plants under the same inoculum load. The area under the disease progress curve (AUDPC) was positively correlated with the percentage disease index and negatively with resistance. Calculation of the apparent infection rate (r) was more informative for natural epidemics than for artificial conditions. The sequential apparent infection rate between observation periods was better correlated with disease progress than was the total apparent infection rate between the first and last observations. A double sigmoidal disease progress curve during the same cropping season was characteristic of some varieties when fungal infection took place during the vegetative phase of crop growth. [ABSTRACT FROM AUTHOR]