Renewable Energy

This paper reports the design, implementation and testing of an indirect solar potato dryer. Indirect solar drying is the new technique of product drying. It is very efficient method than the direct type of solar drying. In this method the atmospheric air is heated in flat plate collector. This hot air then flow in the drying cabinet or drying chamber where potatoes slides are stored. Therefore moisture from the potatoes slides may lost by convection and diffusion. This method of drying is used to avoid direct exposing to the solar radiation. This method mainly reduces the disadvantages of direct solar drying. The experimental set up used for testing the performance of an indirect solar food dryer and determining the influence of various drying methods on the drying behavior of fresh potatoes slides. Evaluation of the dryer was centered on the moisture content reduction and temperature variations. 2 kg of fresh potatoes slides was used for evaluation. Temperatures of the drying chamber (drying cabinet), solar collector and ambient air were taken daily using digital sensors on an hourly basis from 9:00 am to 5:00 pm. Moisture content was taken at the beginning and at the end of each drying day. The test results gave temperature above 65 oC in the flat plate collector (solar collector), 50 oC in the drying cabinet, and the moisture content of 2 kg of fresh potatoes slides reduced to about 66.1 % in five days of drying.

In a dynamic of protection of the environment and sustainable development, solar energy is one of the essential solutions to the energy problems of developing countries and to limiting greenhouse gas emissions. In this work, we compare the energy productivities of photovoltaic installations in four cities of two countries (Morocco and Burkina Faso). Government energy policies in both countries place a strong emphasis on solar photovoltaics. We then chose to make a detailed evaluation of the performances of the various photovoltaic technologies under various climatic conditions in these countries. PVsyst software is used to model the performance of a photovoltaic solar power plant connected to the 6kWc network (2kWc per technology) using three silicon-based photovoltaic technologies, namely: polycrystalline (pc-Si), monocrystalline (mc-Si) and amorphous (a-Si) in two cities per country. The comparative analysis included annual energy efficiency, performance ratio, annual energy density and system efficiency. From these performances, it can be observed that PV installations with a-Si have the highest energy yields and performance ratios (Er-Rachidia, Ouagadougou and Bobo-Dioulasso), while in Mohammedia, energy efficiency and maximum performance ratio are given by pc-Si technology. The mc-Si installation has the maximum overall efficiency of the system as well as the annual energy density in the cities selected for this study. The production of the city of Mohammedia is validated by the actual production of a 6kWc installation (2kWc per technology) made up of three mini-power plants, one with polycrystalline silicon, one with monocrystalline silicon and the other with amorphous silicon. Comparing the data validates our results.

Vibration technique in a machine condition monitoring provides useful reliable information, bringing significant cost benefits to industry. By comparing the signals of a machine running in normal and faulty conditions, detection of faults like journal-bearing defects is possible. This paper presents an appropriate procedure for the fault detection of main engine journal-bearing based on vibration analysis. The frequency-domain vibration signals of an internal combustion engine (IC engine) with normal and defective main journal-bearings were obtained. The signal processing technique plays one of the important roles for recognizing the journal-bearing fault in the proposed system. In the present research, the data mining method based on feature extraction and selection is proposed. The database is established by the feature vectors of frequency domain signals which are used as input pattern in the training and identification process. The SVM and KNN is proposed to identify and classify the journal-bearing fault conditions in the condition monitoring system. The experimental results verified that the proposed diagnostic procedure has more possibilities and abilities in the fault diagnosis of the main journal-bearing of IC engine.

Nowadays, tractor is one of the most important power sources in agriculture. Replacement of tractor is one of the most important decisions that should be made by farmer. Proper performance in this case can lead to timely, high quality farm operations which in turns results in considerable decrease in product expenditures and also more income. The current study was performed in order to determine economically optimum life of MF285 tractors in Debal Khazaei Agro-Industry Co. in Khuzestan province of Iran. Moreover, listed price of tractor, annual depreciation and Internal Rate of Return in the study period were calculated. Then, these items accompanied by their repair and maintenance cost were used to determine their economic life. Finally, replacement time for the study tractors was obtained equal as 6981 hours. These hours of operation are performed in about 14 years and thus the tractor should be replaced.

In this work Mahua oil cake was used to extract the bio oil using fixed bed fast pyrolysis experiments. The effects of three parameters on the pyrolysis efficiency were tested to identify the optimal bio oil production. The parameters are temperature, nitrogen gas flow rate and feed stock particle size. The Response Surface Methodology (RSM), with a Box Behnken Design (BBD), was used for modelling and optimizes the process parameters. The results showed that the second-order polynomial equation explains adequately the non-linear nature of the modelled response. An R2 value of 0.9318 indicates a sufficient adjustment of the model with the experimental data. The optimal conditions found to be at the temperature of 550°C, N2 flow rate of 0.3 lpm and particle size of 4 mm. The yield of bio-oil was obtained 25.90 wt %. In addition the bio oil was characterized by elemental the gas chromatography - mass spectrometry (GC- MS) were analyzed.

The current work presents a theoretical study of the solar power plant with parabolic trough solar collector, the power generated from the solar power plant was calculated with using the thermal storage system without using such a system then comparison between the two cases. The calculations of the thermal storage system in terms of the size of the thermal tank and the temperature of the heat transfer fluid inside the thermal tank as well as its mass are implemented. The theoretical study are completed at Baghdad city (Long. of 44.25° East and Latit. of 33.19° North). The results were obtained by simulating the solar power station with parabolic troughs for both cases by using the thermal storage system and without it. During this work, some hypotheses were created to facilitate the solution of the system of equations for such plants. It was assumed that the specific heat of the heat transfer fluid in the tank of heat accumulation system was constant, It was calculated at the outlet temperature solar field for the heat transfer fluid, which was up to 390 °C, in addition to other hypotheses will be identified during the study steps. As a key to solving the issue was initially calculated direct solar radiation for Baghdad city and the result indicates that the frequency distribution of direct solar radiation was not more than 14% of the radiation values which less than 500 W/m2. Thus, the results leads us to the inference that during the months of low temperature in a city such as Baghdad, don't need a large increase in the size of the solar field or keep the solar field as it is and use thermal storage system, be in our case with a small size which is therefore reflected that be a reasonable cost. The power generated from the solar power plant was also calculated for both cases without the use of thermal storage systems and with it, where the capacity of the solar power plant under study with a value of 50 MW, It is noted that the maximum value of the net power was achieved during some months of the year, especially in June, July and August. As for thermal storage, it is clear that the station is work for more than 20 hours during the day in June, July and August. Therefore, the results obtained in this study were compared with the results obtained from the Solar Advisor Model, which was implemented by the National Renewable Energy Laboratory in the United States of America. There was a reasonable consensus in the results, but it does not match exactly because the working conditions of both cases, the geographical position and the situation is completely different weather but remains the general behavior of the two stations is similar.

Wavelet analysis is one of the most powerful and latest tool in the field of signal processing. It provides the better resolution in time and frequency domain simultaneously. Because of these properties of the wavelet it can be effectively used in EMG signal processing in order to determine the certain changes in amplitude at certain frequencies. At different levels of various mother wavelets we can get the useful resolution component from the EMG signal. In this paper, a single-channel electromyogram acquisition system Biopac MP36 was used to obtain the surface electromyogram signal. Single pair of surface electrodes was used to measure and record the EMG signal on forearm muscles. Then different levels of Daubechies Wavelet family were performed to analyze the EMG signal. We have used root mean square (rms) value of the EMG signal at different level of wavelet coefficients and reconstructed wave. The experimental results shows that rms feature vector provides very good performance for the classification of patterns.

Solar energy applications have become one of the most promising alternatives to electricity production. Solar cells are also being used to equip many isolated consumers in areas far from the central grid around the world. In this experimental work, the effect of solar radiation on solar cell output such as voltage, current, and efficiency of a solar panels was investigated in the conditions of the city of Baghdad, Iraq climates. The data has been recorded using calibration devices. An analysis of the relationship between the intensity of solar radiation and the cell output was performed for voltage and efficiency. The results of the study show that the relationship between the intensity of solar radiation and cell output is a direct and very important relationship if not the most important among all the atmospheric variables. That increasing the intensity of solar radiation caused an increase in current output which means greater cell efficiency.

This research is carried out to study the used of SPC tools towards identifying the variation in quality finished product at Bio-organic fertilizer company. The objectives of this research are to analyze and monitor quality of finished product using Xbar R chart and identify the relationship between variables using scatter diagram. Data was obtained from Quality Department through finished product of 5.5.5PE from January 2008 until December 2008. This finished product can be measure according to pH, moisture, and crash. SPSS version 11.5 software has been used to analyze and interpret the data into control chart and scatter diagram. The unstructured interview with respective workers was done in order to support the data analysis. The finding revealed that the SPC tools can determine process variation in finished product through systematical analysis with more accurately. Since All Cosmos has no specific tool to analyze the data, it is suitable for them to implement this tool.

In developing country like India, energy is most important to economical development of country thus energy sector plays an important role to increase in energy dependence and investment made on it. As we all know the compressed air generation consumes energy. Normally the compressed air system is an overlooked area in most of the industry but compressed air system is a costly source of energy about 7 to 10 times more expensive than electricity. Better methodology for design of energy efficient compressed air system, better maintaince practices and through energy efficiency measures can save the significant amount of energy of any industry. In this paper we have discussed the methodology for design of compressed air system for energy efficient compressed air system for industry. This paper also gives the comparative study of existing compressed air system of one industry with new optimized designed compressed air system for same industry using their specification.