A low power, low cost, high utility value photovoltaic power generating system has been designed and developed with an intention of catering to the needs of the rural population located in far flung villages or hilly regions where electricity supply is either unavailable or is erratic. The proposed solar photovoltaic system has been subjected to rigorous performance evaluation using the four widely used performance metrics namely, Energy Gain, Panel Efficiency, Capacity Utilization Factor (CUF) and Performance Ratio (PR). Performance wise, the proposed single axis tracking system has been proved to be quite advantageous when compared to the latitude-tilt fixed panel system. It now becomes mandatory to ensure that the single axis system is also economically viable. Since the target customers belong to economically weaker strata of the society, the system has to be financially attractive if it has to have widespread acceptance. Financial analysis of the proposed system was carried out using two most trusted methods viz. NPV and IRR methods to ensure the system will return better economic benefits. The net cost of the proposed single axis sun tracking system is INR. 4066.00 and that of the latitude-tilt fixed panel is INR. 3413.00. Financial analysis using NPV method has shown that both the latitude-tilt fixed panel system and the single axis sun tracking systems have positive values of NPV (INR. 3237.02 for fixed tilt system and INR. 4997.12 for single axis sun tracking system). Hence both the project proposals can be accepted since both will be economically feasible for the investor. The financial analysis of both the latitude-tilt fixed system and the single axis tracking system was carried out using IRR method. Results of this financial analysis, show that the latitude-tilt fixed system has returned a value of 13.124% which is less than the normally acceptable value, while the IRR value obtained for the single axis tracking system is 15.491 % which is more than the normally specified level. Thus, the proposed single axis sun tracking system is a better option than the latitude-tilt fixed panel in terms of power output and also in terms of financial analysis

Experimental studies were carried out using 37 W photovoltaic (PV) panels under different weather conditions over a prolonged duration of time to evaluate the performance of a low cost tilted single axis tracking system in comparison with a horizontal single axis tracking system and two fixed PV systems. A horizontal single axis PV panel tracker (HSAPVPT) and a tilted single axis PV panel tracker (TSAPVPT) were set up to compare their performance with a fixed horizontal PV panel (FHPVP) and another fixed tilted PV panel (FTPVP) inclined at an angle equal to the latitude (22o 43’, north latitude) of Indore city, Madhya Pradesh (India). Performance evaluation of both the single axis trackers was carried out during the entire month of October 2016 under varying climatic conditions. Performance of both the single axis trackers was observed to be exemplary under bright and sunny conditions with maximum duration of direct solar irradiance. However, performance of both the trackers deteriorated with decrease in duration of direct solar irradiance due to cloudy and heavily overcast conditions. All relevant geographical and seasonal details as well as ambient conditions, which decide the performance of PV systems, have been clearly mentioned to help in analysis and comparison of PV systems developed by other researchers. A unique feature of these tracking systems is that energy consumption of the tracking systems was quite low at around 1.1 % of the per day energy generated on sunny days. It is also experimentally established that average energy gain during the month of October, 2016 of a TSAPVPT system was 31.91 % while that of a HSAPVPT system was 18.05 % and hence can be used with advantage. Keywords: Horizontal single axis sun tracker, tilted single axis sun tracker, low cost sun tracking systems, energy gain Cite this Article S.P. Singh, K. Srikant, K.S. Jairaj. Performance Evaluation of a Tilted Single Axis Photovoltaic Tracking System under Different Weather Conditions. Journal of Alternate Energy Sources and Technologies . 2017; 8(2): 45–55p.

Drying characteristics of Thompson seedless (Green) and Sharad seedless (Black) grapes were obtained using a simple laboratory scale hot air dryer. Grapes were dipped for three minutes in a solution prepared by adding 25 g Potassium carbonate and 15 mL Ethyl oleate to 1 liter of distilled water maintained at a temperature of 40°C. Grapes were dried using hot air at a temperature of 60°C and a flow rate of 0.82 mls created by chimney effect. Green grapes with an initial moisture content of 79.94 % required 19 hrs while Black grapes with an initial moisture content of 81.38 % required 27 hrs to reach a final moisture content of 18 % (wet basis). Drying rate constant value for Green grapes was 0.036505 h-1 while that for Black grapes was 0.024793 h-1 . Raisins produced from both variety grapes possessed all the required quality parameters acceptable in the international market.

The present article highlights the developments made in the field of indigenization of the technology for preparation of cobalt shapes for radioisotope applications from a secondary resource. In the first step, the process of extraction of cobalt in the form of metal powder from a secondary indigenous resource as spent ammonia cracker catalyst is described. In the second step, the processes of conversion of cobalt metal powder into the desired shapes followed by coating over the finished products have been presented.

Drying kinetics of materials may be described completely using their transport properties together with those of the drying medium. In the case of food drying, the drying rate constant 'k' was used instead of transport properties. The drying rate constant combines all the transport properties and may be defined by the thin layer equation. A large number of investigators have worked on solar drying of grapes and the drying rate constant has been calculated through conditions of drying product temperature, equilibrium relative humidity, equilibrium moisture content and drying time. Several mathematical models have been proposed to describe the moisture movement in the drying product. Among the thin layer models, the exponential model is found to be simple and most suitable to describe drying characteristics of grapes. The exponential model considers only the surface resistance, implying that all the resistance is concentrated in a layer at the surface of the drying product. Drying characteristics obtained from experimental results of some investigators were taken into consideration to estimate the value of drying rate constant for grapes. The best fit for drying rate constant value was selected from among the various drying curves obtained experimentally by investigators till date.

(Abstract) AC motors have gained wide ranging applications in the present day scenario. Adoption of innovatively designed speed control mechanisms in the industrial sector has revolutionized these drives. Now-a-days the industrial sector has a well organized power supply system, wherein motors used for specific industrial applications are not subjected to abrupt supply variations. Thus their operating conditions remain nearly the same throughout their life span. There are certain areas like the agricultural sector which use AC motors without any speed control mechanisms. In the agricultural sector, water pumps are used for irrigating small tracts of land from tube wells or open wells. Small and marginal farmers with lands along the banks of rivers have open wells even today with irrigation pumps. The three phase AC motors which are coupled to these pumps are subjected to a wide power supply voltage fluctuations depending on their distance from the distribution transformers. Supply voltages at motor terminals are never constant throughout the day and night. They are subjected to wide voltage fluctuations during different periods of the day and night. The most common problem faced by farmers is the burnout of motors. In order to ascertain the main reasons for burnout of motors used in irrigation pumps and observe their performance under variable supply voltage and load conditions, an experimental model was set up in the laboratory and relevant tests were carried out by simulating field conditions. It was observed from experimental results that with higher and lower values of supply voltage to the motor, the current drawn was higher and resulted in increased losses thereby creating higher thermal stresses. The basic idea of reducing losses could be achieved by using good quality core and conductor material for the motor, which would minimize thermal stresses. It could be finally summarized that an Energy efficient induction motor as per specific needs of the agricultural sector has to be designed and manufactured keeping the cost factor in mind.

This paper attempts to review various solar dryers developed exclusively for grape drying on a normal scale. Many popular varieties of solar dryers, certain typical models as well as traditional methods practiced for drying grapes are presented in this paper. Technical and economical results have proved that solar drying of grapes is quite feasible. Commercialization of solar drying of grapes has not gained momentum as expected, may be due to high initial investment and low capacity of the dryers. Even, the farmer’s acceptance of solar dryers developed is not encouraging. Exhaustive research and development work has to be carried out in order to make solar drying of grapes economical and user friendly. There has been a remarkable achievement in solar drying of grapes due to sustained research and development associated with the adoption of advanced technologies. A review of various solar drying models for grapes is thus necessitated.

The highest prevalence of type 2 diabetes mellitus in developing countries occurs in the upper socio-economic group, but this has not been well documented in Indians. The age and sex standardized prevalence of diabetes in 1112 affluent adult Indian subjects was 21.1%. This is the highest prevalence of diabetes reported from India.

A process was developed to produce >99.9% pure cobalt oxalate from spent ammonia cracker catalyst pellets containing ∼20% Co generated at heavy water plants. A pilot plant for producing kilograms of cobalt oxalate of required purity has been set up. The process consists of leaching, oxidation, solvent extraction, ion exchange and oxalate precipitation. The major impurities present in the leach liquor after nitric acid oxidation were Fe3+, Al3+ and Ni2+. Fe3+ and Al3+ were separated from the leach liquor by using a solvent extraction (SX) process employing a mixed extractant system consisting of D2EHPA and TBP. Ni2+ was separated by ion exchange (IX) employing Dowex M4195 resin.

During the development of a solvent extraction process for the separation of nickel and cobalt from ocean nodule sulphate leach liquor, there was a need for fast and accurate analytical method for determination of these elements in various process streams. For the determination of copper, nickel and cobalt which are present in gm/litre level, simultaneous visible spectrophotometric method developed in our laboratory was employed. Iron which is present at <0.2 g/l was estimated by atomic absorption spectrophotometry. It has been found that Iron (III) seriously interferes with the determination of nickel giving almost 10% higher values as confirmed by classical gravimetric method. Therefore, an attempt has been made to develop a East and accurate method for the simultaneous determination of copper, cobalt, nicker and iron by visible spectrophotometry. The method developed eliminates the need for separate estimation of iron by atomic absorption spectrophotometry and nickel by gravimetry.