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A hot box solar cooker with used engine oil as a storage material has been designed, fabricated and tested so that cooking can be performed even in the late evening. The performance and testing of a storage solar cooker have been investigated by measuring stagnation temperatures and conducting cooking trials. The maximum stagnation temperature inside the cooking chambers of the hot box solar cooker with storage material was the same as that of the hot box solar cooker without storage during the day time, but it was 23 °C more in the storage solar cooker from 1700 to 2400 h. The efficiency of the hot box storage solar cooker has been found to be 27.5%. Cooking trials were also conducted. The rice and green gram washed split were kept at 1730 h, and these were cooked perfectly by 2000 h in the hot box storage solar cooker, while these were not cooked in the hot box solar cooker without storage.

Over the years, many diagnostic/condition monitoring tests are in vogue for evaluating the health of HV machine insulation. While it has been possible to assess the general state and condition of the stator insulation, experience gained so far has shown that these diagnostic tests are not sensitive to detect or predict the breakdown or failure of the insulation, which is a microscopic phenomenon. In other words, the conventional diagnostic tests such as dissipation factor, capacitance, polarisation index, DC leakage current measurements are average/integrated effects and are not capable of reflecting the microscopic phenomenon such as an insulation breakdown. In view of these facts, there is a need to device a test method or to find a more searching and sensitive parameter capable of predicting the insulation breakdown. In this context, partial discharge measurements assume greater importance as it is believed that partial discharges (PD) are capable of revealing the incipient faults. The paper presents the partial discharge degradation studies carried out on the stator bars of 1.1 kV. 135 MW hydrogenerator. The generator bars have been subjected to accelerated electrical ageing and the partial discharges have been monitored periodically using Multichannel Analyser (MCA) in order to characterise the ageing phenomena. The MCA provides the distributions of partial discharge pulse magnitudes against their repetition rates. The distribution profiles have been examined in detail in order to characterise the internal discharges, slot discharges and endwinding discharges that occur in the stator winding.

The third zone protection of distance relay serves as a backup for fault on the longest transmission line which is adjacent to the line to be protected. For the accurate detection of fault, its reach setting is curtailed to 100% of the primary line plus 100% of the adjacent longest line. Such an arrangement is essential mainly for a dedicated transmission systems. But some critical power system operating conditions may develop during which the operation of the third zone protection will be challenging. Under such dependable situations, the positive sequence apparent impedance tries to penetrate into the zone characteristics and distance relay provides spurious tripping. In this study, such cases have been considered and simulated using EMTDC/PSCAD software considering the Indian Eastern Regional Grid (IERG) system.

Abstract Small hydropower projects (SHPs), though generally considered more environmentally benign and socially acceptable as compared to large projects, yet their overall sustainability is under suspicion in the Himalayan regions. Almost all SHPs in this region are being developed as run of the river mode which generally causes less/no submergence and quite less displacement of people as compared to large reservoir based hydropower production mode. However, in the absence of proper planning and monitoring mechanism, these projects are causing implacable tunnelling of hills, choking of streams, conversion of streams into dry ditches and long term socio-environmental impacts. This paper presents a SHP development study from hydro rich Beas river basin of Himachal Pradesh, a state nestled in western Himalayan region of India. In depth field studies, focus group discussions with the project affected people and interaction with project proponents of five SHPs in this region suggest that sustainability issues with respect to SHPs are not small vis-a-vis size of their installed capacity. There is an urgent need to take steps to include SHPs having an installed capacity of above 10 MW into the ambit of environment clearance process which is absent in many countries of the world at present.

This research article intends to discuss on the role and effects of dispersing solution combustion derived magnesia nanoflakes (~17 nm) within the biodiesel-diesel blends and pure diesel termed as nanofuels, in order to investigate the functional and pollutant emissions of a single-cylinder, electrically loaded, water-cooled diesel engine. The fuels focussed in this study are a blend of palm oil biodiesel and regular diesel dispersed with 50 ppm magnesia nanoflakes, and a pure diesel dispersed with 50 ppm magnesia nanoflakes. These fuels are compared with regular diesel which is considered as the base reference fuel, as well as with the biodiesel-diesel blend. From the experimental measurements, we inferred that the fuel density, viscous nature, and calorific value enhanced with the addition of nanoflakes. As for the engine performance attributes, the brake specific fuel consumption (BSFC) is lessened by 3.08% and 2.88% for particle dispersed biodiesel-diesel blend and particle dispersed diesel, respectively, whereas the brake thermal efficiency (BTE) enhances by 5.04% for particle dispersed biodiesel-diesel blend and 2.74% for particle dispersed diesel. With reference to emission, the unburnt hydrocarbon (UHC), white damp (CO), particulate exhaust or smoke, and the nitrogen oxides (NOx) are reduced by 9.51%, 18.71%, 13.64%, and 5.63%, respectively for particle dispersed biodiesel-diesel blend and 10.35%, 16.54%, 13.64%, 19.47%, and 4.70%, respectively for particle dispersed diesel.

Gamma ray exposure buildup factor for some ceramics such as boron nitride (BN), magnesium diboride (MgB2), silicon carbide (SiC), titanium carbide (TiC) and ferrite (Fe3O4) has been computed using five parametric geometric progression (G.P.) fitting method in the energy range of 0.015 to 15.0 MeV, up to the penetration of 40 mean free path (mfp). The variation of exposure buildup factors for all the selected ceramics with incident photon energy, penetration depth, and chemical composition has been studied.

This study examines the dynamics of return and volatility connectedness between the rare earth stock index and the indexes of clean energy, consumer electronics, telecommunications, healthcare equi...

Abstract A method to analyze multi-area optimal power flow in novel energy management systems is proposed and studied in this paper. The studied power network consisted batteries, distributed generators and electric parking lots. A straightforward granular-based method is introduced to maintain the simplicity of the calculations while the independency of areas is preserved. In this case, a three-area power network as a multi-area power network problem is chosen to test and approve the applicability of the proposed method in terms of accuracy, simplicity, preserving independency, and not requiring any control or initial parameters. According to the results, maximum error is 0.0009 pu in the selected case study. Moreover, two valued variables namely operation cost and voltage deviation are selected as the two fundamental objective functions to be analyzed both multi-objectively and solely. Furthermore, in this paper, soon-to-be-indispensable electric vehicle parking lots and distributed generators are also utilized to optimize operation cost (up to 49.28%) as well as voltage deviation (up to 48.99%). Also, the influence of each area on one another in multi-area layout is studied. In one scenario, the third area is equipped with battery and fuel cell to improve voltage deviation of itself (40.42%) as well as first and second area 12% and 15.4%, respectively.