Top PDF Evaluation Of Electricity Generation From Animal Based Wastes In A Microbial Fuel Cell

Evaluation Of Electricity Generation From Animal Based Wastes In A Microbial Fuel Cell

Evaluation Of Electricity Generation From Animal Based Wastes In A Microbial Fuel Cell

Since the turn of the 21st century MFCs have started to find a commercial use in the treatment of wastewater [4]. Developing new method of energy using renewable and carbon-neutral sources has opened up a new approach to energy supply. Power generation through the utilization of biomass has proved to be a possible path in achieving economic, social and environmental sustainability in the country. Unlike a battery, a fuel cell does not store energy. Instead, it converts energy from one form to another (much like an engine) and will continue to operate as long as fuel is fed to it. A MFC uses bacteria to catalyze the conversion of organic matter into electricity by transferring electrons to a developed circuit [5]. Cell growth was inhibited substantially when these microbial fuel cells were making current, and more oxidized end products were formed under these conditions and that sludge production can be decreased while electricity is produced in fuel cells [6]. Fuel cells that use bacteria are classified as two different types: biofuel cells that generate electricity from the addition of artificial electron shuttles (mediators) and microbial fuel cells (MFCs) that do not require the addition of mediator. The first step requires the removal of electrons from some source of organic matter (oxidation), and the second step consists of giving those electrons to something that will accept them (reduction), such as oxygen or nitrate. This technology can use bacterium already present in wastewater as catalysts to generating electricity while simultaneously treating wastewater [7]. Single chamber MFCs treat roughly 50 to 70% of the chemical oxygen demand (COD) present in wastewater in a 12 hour time span [8]. Unlike conventional fuel cells, MFCs have certain advantages like high energy-conversion efficiency and mild reaction conditions. [3] In addition to microorganisms that can transfer electrons to the anode, the presence of other organisms appears to benefit MFC performance. It is reported that, a mixed culture generated a current that was six fold higher that that generated by a pure culture [9]. If certain bacteria are grown under anaerobic conditions (without the presence of oxygen), they can transfer electrons to a carbon electrode (anode) The electrons then move across a wire under a load (resistor) to the cathode where they combine with protons and oxygen to form water. When these electrons flow from the anode to the cathode, they generate the current and voltage to make electricity. Among the electrochemically active bacteria are, ________________________
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Energy generation in a Microbial Fuel Cell using anaerobic sludge from a wastewater

Energy generation in a Microbial Fuel Cell using anaerobic sludge from a wastewater

ABSTRACT: In microbial fuel cells (MFCs), the oxidation of organic compounds catalyzed by microorganisms (anode) generates electricity via electron transfer to an external circuit that acts as an electron acceptor (cathode). Microbial fuel cells differ in terms of the microorganisms em- ployed and the nature of the oxidized organic compound. In this study, a consortium of anaerobic microorganisms helped to treat the secondary sludge obtained from a sewage treatment plant. The microorganisms were grown in a 250 mL bioreactor containing a carbon cloth. The reactor was fed with media containing acetate (as the carbon source) for 48 days. Concomitantly, the electrochemical data were measured with the aid of a digital multimeter and data acquisition system. At the beginning of the MFC operation, power density was low, probably due to slow mi- croorganism growth and adhesion. The power density increased from the 15 th day of operation,
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Characterization of exoelectrogenic bacteria enterobacter strains isolated from a microbial fuel cell exposed to copper shock load.

Characterization of exoelectrogenic bacteria enterobacter strains isolated from a microbial fuel cell exposed to copper shock load.

reduction of Fe and Mn oxides [33], electricity production in bioelectrochemical systems [34], and interspecies electron transfer in anaerobic microbial aggregates [35–36]. Hence, cytochrome c was used as the indicator for the characterization of an electroactive biofilm using Raman microscopy [37]. Cytochrome c produced strong, representative and reproducible Raman spectra when excited with a 532 nm wavelength due to the enhancement of the Raman scattering (Raman resonance effect) of the porphyrin ring in visible and ultra-violet bands [37]. Thus, a Raman experiment was conducted to investigate whether the two isolated strains contained cytochrome c. According to the results (Figure 4), four typical Raman peaks of cytochrome c (751, 1132, 1318, and 1586 cm 21 ) were observed for the two isolated strains, indicating the potential high densities of cytochrome c in them. Previous studies reported that cytochrome c associated with bacterial outer membrane and conductive pili could be used for direct electron transfer [4]. Interestingly, the isolated bacteria have a large number of pili as shown in the electron microscopic images (Figure 2), and pili of exoelectrogens might serve as microbial nanowires to aid in the electron transfer from the cell surface to the surface of Fe(III) oxides [6]. In addition, a previous study has proposed that in situ oxidation of produced hydrogen might also contribute to the mechanism of electricity generation by Entero- bacter aerogenes biofilms [38]. Hence, further experiments are required to confirm the exact mechanism which is employed by the isolated bacteria to transfer electron to the surface of insoluble electron acceptors.
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Microbial fuel cells used in the production of electricity from organic waste: a perspective of future.

Microbial fuel cells used in the production of electricity from organic waste: a perspective of future.

MICROBIAL FUEL CELLS USED IN THE PRODUCTION OF ELECTRICITY FROM ORGANIC WASTE: A PERSPECTIVE OF FUTURE. In this review is presented an innovative technology for use of animal and vegetable waste with high pollution levels in microbial fuel cell (MFC) as an alternative to waste remediation and simultaneously producing electricity and fertilizer for agriculture. A brief history of MFC, the studies about the electron transfer mechanisms, discussion of the biological nanowires in bacteria and the use of chemical mediators or carriers of electrons are explained. The factors inluencing the performance of MFCs, the application in waste and sewage treatment and power generation are also discussed.
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ACETONE REMOVAL AND BIOELECTRICITY GENERATION IN DUAL CHAMBER MICROBIAL FUEL CELL

ACETONE REMOVAL AND BIOELECTRICITY GENERATION IN DUAL CHAMBER MICROBIAL FUEL CELL

including plain graphite, carbon cloth, graphite foam, graphite granules and high surface area graphite fiber brush electrodes (Chaudhuri and Lovley, 2003; Fan et al., 2007; He and Angenent, 2006). Cation Exchange Membranes (CEMs), Anion Exchange Membranes (AEMs) and ultra-filtration membranes (Kim et al., 2007; Rozendal et al., 2006) are common separators between the electrodes. Since the cathode is usually a limiting factor in power production in of an MFC (Rismani-Yazdi et al., 2008), various electron accepters, such as ferricyanide and permanganate (He and Angenent, 2006; Rabaey et al., 2004; You et al., 2006), have been used as catholytes in two-chamber MFCs, to enhance performance of the cathodic compartment. Oxygen for its high thermodynamic redox potential, good self- sustaining operation and availability (He and Angenent, 2006), commonly used as an electron accepter. Last researches showed that different wastewaters can be used as substrate and also inoculums for MFCs, to lead energy production from an abundant and inexpensive source. Most of the energy available from the oxidation of the organic load was converted to electricity while the remaining energy was used for microbial growth (Aldrovandi et al., 2009; Du et al., 2007; Wen et al., 2009). Currently wastewater MFCs are being considered as a renewable energy strategy (Wen et al., 2009). In this experiment, the performance of a two chambered MFC with synthetic wastewater as substrate was studied. The influences of different mediator, oxidizer and rate of aeration on voltage, power density and COD removal efficiency of MFC were investigated.
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Avaliação da resistência externa na geração de energia elétrica por célula combustível microbiológica/  Evaluation of external resistance in the generation of electric energy by microbiological fuel cell

Avaliação da resistência externa na geração de energia elétrica por célula combustível microbiológica/ Evaluation of external resistance in the generation of electric energy by microbiological fuel cell

The objective of this work was to study the influence of external resistance on energy generation from a double chamber microbiological full cell (MFC) inoculated with the sediment of Patos Lagoon estuary. The MFC was build with acrylic plates that constitute the anodic and cathodic compartment, both with volumes equal to 1 L, separated by a cationic membrane and with the presence of a graphite plate as the system electrode. The anode compartment is fed with CH3COOH substrate, kept under constant stirring, at 35 ºC and pH 7.5. The voltage generated by the system is measured by an Arduino microcontroller, which is responsible for data acquisition and storage. In the startup of the experiment an external resistance of 1000 Ω was used, which was reduced to 56 Ω after the polarization curve and resulted the maximum power in the system of 335.32 mW/m². Thus, it can be concluded that MFC directly converts chemical energy into electricity through the use of exoelectrogenic bacteria, which makes it a promising technology to be used as an alternative to fossil fuels in power generation, as well as reducing environmental impact.
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Proton Exchange Membrane Based on Sulfonated Poly (Aromatic Imide-Co-Aliphatic Imide) for Direct Methanol Fuel Cell

Proton Exchange Membrane Based on Sulfonated Poly (Aromatic Imide-Co-Aliphatic Imide) for Direct Methanol Fuel Cell

In this work, a new sulfonated poly(aromatic imide-co- aliphatic imide) (SPI) with different degrees of sulfonation were synthesized from 4,4'-diaminodiphenylmethane (DDM), sulfonated 4,4'-diaminodiphenylmethane (S-DDM), hexamethylenediamine (HDA), and 3,3',4,4'-benzophenone- tetracarboxylic dianhydride (DTDA). The structure design of this SPI membrane was to combine the hydrophilic part namely the sulfonic acid side group to increase proton conductivity, and the hydrophobic aromatic polymer backbone to increase strength and flexibility and to lower methanol permeability. Fourier transform infrared spectroscopy was used to determine the structure of the synthesized sulfonated copolyimides. The ion exchange capacity (IEC), thermal stability, water uptake, degree of sulfonation (DS), proton conductivity, and methanol permeability were measured and investigated and compared with the commercial Nafion membrane.
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Matéria (Rio J.)  vol.21 número3

Matéria (Rio J.) vol.21 número3

The next step, still utilizing similar materials, had the objective to decrease operation temperatures be- low 850ºC, which was achieved fabricating cells supported either by the anode or by the cathode, for which the supporting electrode possessed thicknesses between 300 μm and 1 mm, and a thin electrolyte, with thick- nesses ranging from 5 to 50 μm. The use of a thinner electrolyte decreased the ohmic loss in the electrolyte, which has allowed operation in temperatures in the range of 700 to 850ºC. This procedure created the inter- mediate temperature solid oxide fuel cells, IT-SOFC [2]. The present development step, representing the third generation of solid oxide fuel cells, is the metal supported cells, MS-SOFC. Furthermore, metallic sup- ports were developed to allow the deposition of all elements that constitute the fuel cell in a controlled way and bearing dimensions suitable for the specific requirements, once a metallic alloy assumed the cell- supporting role. Ferritic steels are frequently used for such application that includes the following iron-based alloys: ITM, with 26 wt% Cr; CROFER 22APU, with 20 to 24 wt% Cr; Sandvik Sanergy, with 22 wt% Cr and type 430 stainless steel, with 22 wt% Cr [3-5]. The MS-SOFC presented important advantages such as to facilitate the fabrication procedures, now associated with a metallic support, gaining robustness, but requiring an electrolyte better adapted in terms of coefficient of thermal expansion with the metals above mentioned and with better ionic conductivity at the lower operation temperatures. Because of that, the YSZ gave place to ceria and other ceria-based mixed ceramic materials.
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Fuel cell technology.

Fuel cell technology.

A empresa alemã MTU, de Friedrichshafen, desenvolveu, recentemente, uma célula a carbonato fundido (MCFC) de 300 kW de potência elétrica, onde por simplificações radi- cais da engenharia e tecnologia da unidade, pôde-se reduzir drasticamente os custos globais, eliminando-se a necessida- de do custoso trocador de calor de alta temperatura. A re- forma endotérmica do gás natural é realizada na própria coluna de unidades de células, eliminando-se o caro reformador e, ao mesmo tempo, resfriando as células. Em Santa Clara, nos Estados Unidos, foi construído um conjun- to de unidades de células MCFC, de 2 MW de potência. Este programa foi muito importante sob o ponto de vista tecnológico, mas sem resultados comerciais. Também recen- temente foram desenvolvidas pequenas instalações de célu- las cerâmicas do tipo HEXIS (Heat Exchange Solid Oxide Fuel Cell), de apenas 10 kW de potência elétrica, para o
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Mathematical Modelling of Leachate Production from Waste Contained Site

Mathematical Modelling of Leachate Production from Waste Contained Site

In this work, mathematical models of leachate production from Waste Contained Site (WCS) was developed and validated using the existing experimental data with aid of MATLAB, 2007a. When the leachate generation potentials (Lo) were 100m3, 80m3 and 50m3, the maximum amount of leachate generated were about 2920m3, 2338m3 and 1461m3 for about 130 days respectively. It was noted that as the leachate percolates through a selected distance, the concentration keeps decreasing for one-dimensional flow in all the cases considered. Decreasing in concentration continues until a point was reached when the concentration was almost zero and later constant. The effects of diffusivity, amount of organic content present within the waste and gravity, as cases, were also considered in various occasions during the percolation. Comparison of their effects was also taken into account. In case of gravity at constant diffusivity, decrease in concentration was not rapid but gradually while much organic content in the waste caused the rate of leachate production to be rapid; hence, giving rise to a sharp sloped curve. It can be concluded that gravity influences the rate of change in the concentration of the leachate generation as the leachate percolate downward to the underground water. When the diffusivity and gravity are put into consideration, the concentration of the leachate decreases gradually and slowly.
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Genetic Algorithm Based PI Controller for Frequency Control of an Autonomous Hybrid Generation System

Genetic Algorithm Based PI Controller for Frequency Control of an Autonomous Hybrid Generation System

In [1,2] hybrid system studies proportional plus integral (PI) controller is used to regulate the output powers from distributed generation system to achieve power balance condition due to sudden variations in generation and load. The gain values of PI controller are chosen by trial and error method. In [10] the conventional PI controller has traditionally been tuned by the method described in Ziegler and Nichols. The controller gains once tuned for a given operating point are only suitable for limited operating point changes. Therefore, the use of the conventional PI controller does not meet the requirements of the robust performance [10]. Moreover, when the number of parameters to be optimized is large, conventional technique for optimization is certainly not preferred one. In this article, the genetic PI controller is designed based on a conventional controller’s concept except that their gains are tuned on-line as operating point changes. The GA is finding widespread applications in systems optimizations. As an intelligent control technology the GA can give robust adaptive response with nonlinearity, parameter variation and load disturbance effect [3–5]. Basics of Genetic Algorithm are illustrated in [9]. The results of applying the genetic PI controller to the hybrid-power system are compared to those obtained by the application of a conventional PI controller. Simulated results show that the genetic PI controller provides improved dynamic performance than fixed gain conventional controller. The genetic controller also shows better transient performance for load disturbances.
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The Impact of Feed-in policies on Renewable Electricity Generation in Spain

The Impact of Feed-in policies on Renewable Electricity Generation in Spain

According to the laws mentioned, one of the criteria in attributing subsidies is to diminish the risk of the investment to producers. Thus, support mechanisms attributed to producers of renewable sources are a kind of guaranteed subsidy for a maximum period of twenty-five years (depending on the type of technology). Hence, laws 2/2013 and 9/2013 are only applicable to new producers. Therefore, the negative impact of both FiTs and FiPs on the electricity production from wind source could be reflecting the subsidies that are still being paid to old producers, effectively becoming a rent for the economy. Both FiTs and FiPs are paid on top of the wholesale electricity market price, so that the additional tariff paid by consumers will always increase the wholesale price. Hence, consumers decide to consume less, and the demand curve goes down. With less demand, producers will adjust their supply, reducing electricity production (the supply curve moves to the left). Even though FiTs are paid according to the electricity produced, the producers still benefit from not producing high levels of electricity. Once, the marginal cost is the same while electricity prices increase. In fact, producers could be receiving the tariffs despite not investing them.
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INANCE M ASTERS INF

INANCE M ASTERS INF

Over the last three years, the Ugandan currency has been devaluing against the US dollar but it was in midst October 2014 that a more severe appreciation of the dollar was denoted, which continued up until the last months of 2015. Currently, it seems that even though there is still a devaluation tendency it is at a much slower pace than in the recent past, as the UGX shilling prepares to end the year close at 3,650 per US dollar in 2016, down from UGX 3,372 per US dollar in 2015 40 . This downward pressure is expected to continue due to the substantial current account and fiscal deficits, which in turn will accentuate both of them. The underlying reasoning is that imports are getting more expensive, but are still required, mainly for continuing with the infrastructure investment plan, and exports are cheaper, thus distorting the trade balance. Since 2012, the current account as a percentage of real GDP has been decreasing and, according to Bloomberg estimates, it is expected to end 2016 at -9.1%, whereas the fiscal deficit is expected to account for 4.7% of real GDP and expected to slightly decrease over the next two years. Furthermore, the post-election period of 2011 was followed by high government expenditures, which led to a high inflation levels of 15.1% and to an aggravation of the government debt to GDP from 21.8% in 2010 to 27.1% in the subsequent year. Thereafter, efforts were made to control inflation measurable through its actual decrease during the following years. Currently, the projected CPI for the end of 2016 is 6.7%, with expectations of stabilization at 5% by 2018.
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Generation of Electricity Using Solid Waste Management in  Krishnagiri Municipalty

Generation of Electricity Using Solid Waste Management in Krishnagiri Municipalty

Historically it was ruled by Kongu and Chera rulers. Later the region came under Cholas, Pallavas, Gangas, Nulambas, Hoysalas, Vijaya Nagar and Bijapur emperors, Wodeyars of Mysore and Nayaks of Madurai. This region of Krishnagiri served as "Gateway of Tamil Nadu" and the protective barrier for Southern region defending onslaughts from barriers with motives of imperialism and exploitation. Krishnagiri Fort become the first and forth most defensive place. The majestic fortress built on Krishnagiri hill by the Vijaya Nagar Emperors, stands as testimony still now.
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Carbon capture and storage in the power sector of Portugal and Spain

Carbon capture and storage in the power sector of Portugal and Spain

Lukas Fritz 18 energy and additional installation facilities resulting in increasing costs. This is confirmed by the Department of Energy (U.S), which speaks about challenges related to the currently high capital and operating costs of Air Separation Units. These expenditures are responsible for the major part of the costs in oxyfuel combustion technology. 38 Research and development aiming to reduce the costs of oxygen production will therefore be essential to make oxyfuel combustion more attractive and competitive with pre- and post-combustion carbon capture systems. This includes steady improvements of the cryogenic distillation process, which already led to a significant cost decrease in the past 10 years and investigation efforts for alternative oxygen supply processes such as membranes. 39 Another challenge concerning oxyfuel combustion is the high combustion temperature due to the use of pure oxygen. The combustion of a fuel with pure oxygen leads to combustion temperatures of around 3500°C which is far too high for usually used power plant materials as the combustion temperature is limited to ca. 1300-1400°C for GTCC applications and ca. 1900°C in an oxyfuel coal-fired boiler considering the currently used technology. To overcome the problem of too high combustion temperatures a part of the flue gas and steam or liquid water is recycled back to the combustion chamber. The flue gas obtained from the combustion process has very high concentrations of CO 2 and contains vapor which can be cooled to condense to water in its liquid form. The IPCC
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Energy consumption and investments for economic growth in Southern Africa Development Community (SADC)

Energy consumption and investments for economic growth in Southern Africa Development Community (SADC)

The result shows that fossil fuel energy consumption gives a positive contribution to the economic growth, even though it is on the short run. This result suggests that the subsidies from G20 countries that finance fossil fuel in some countries, makes the fossil fuel energy consume a boost for economic growth. The fossil fuel energy consumption also contributes to the phenomenon of climate change. Kofi Annan (2015), supports this concept of growth by saying that Africa needs to take up the challenge of embracing a judicious and dynamic energy mix, in which renewable sources will gradually replace all fossil fuels, while building the foundation to a competitive energetic infrastructure and low carbon emission. To continue with carbon emission, would be the equivalent to a climate catastrophe, and consequently the economy will be influenced negatively. Having into account the positive relation between the fossil fuel energy consumption and economic growth. The creation of partnership policies between the SADC states member and the investors and cooperation partners, is important to develop necessary infrastructures projects for the energy consume. Most states have big mineral reserves, from which fuel can be obtain, this potential can be used to increase the electricity production that will decrease significantly the lack of electricity.
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A Scientometric Study of Fuel Cell Based on Paper and Patent Analysis

A Scientometric Study of Fuel Cell Based on Paper and Patent Analysis

The data from Table 9 shows that in organizations with more papers or patents production, the workforce also has a stronger capacity for scientific research or technical d e v e l o p m e n t. H o w e v e r, j u s t a s m o s t organizations can only focus on either papers or patents, individuals are often involved in only one of the two as well. It’s rare to find organizations or individuals that are strong in both paper and patent production. As with the top ten authors with highest number of papers, among them, only Xing Wei from the Chinese Academy of Science produced three patents. The rest of the authors have none. Similarly, among the top ten inventors of patents, only Makoto Uchida and Kazuhito Hatoh have published papers, though only five and one paper(s) respectively. The other seven inventors have published none. Among the 20 authors and inventors, none made the top 50 rankings for both categories.
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Endesa, S.A - utilities

Endesa, S.A - utilities

The methodology applied for Endesa’s valuation is a Sum of the Parts approach (SoTP), which entails the segmentation of the company businesses into four different parts: conventional Generation & Supply, Renewables, Distribution and Structure, Consolidation Adjustments and Eliminations. This is in line with the segmentation suggested and reported by the company. For all the segments a DCF analysis was carried out. However, for the last one, hereby called Structure, the valuation is carried out through a EV/EBITDA multiple, due to its correlation to the other segments and its volatility and lack of predictability. As a matter of fact, it is not possible to predict how adjustments and consolidations will be in the following periods, which is why a multiple of the whole company is used, so as to englobe the whole operations and the segments interconnections. As the multiple EV/EBITDA for G&S in 2016 stood in 6.2 and the EBITDA expected in 2018 for Structure is of negative €126M, the valuation for this segment is of negative €781M. For the remaining three segments, the DCF valuation is carried out in full, with a distinct WACC analysis for each of the segments. Also, there is a separate multiple valuation, through the analysis of the peers’ multiples. All in all, a final value of €20.39 per share is reached, where a clear emphasis on the value of Distribution, followed by conventional G&S (Figure 27).
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Effect of Sulfonation of SEBS Copolymer on the physicochemical properties of Proton Exchange Membrane

Effect of Sulfonation of SEBS Copolymer on the physicochemical properties of Proton Exchange Membrane

2) Ion Exchange Capacity (IEC):The ion exchange capacity is defined as the number of moles of SO3 per gram of polymer fixed, indicating the capacity of the ion transfer membrane [6]. The ion exchange capacity (IEC) of SEBS were determined by the titration method [7] The samples were immersed in a solution of HCl for 24 hours. Later immersed in 50 ml of 1M NaCl for another 24 hours to produce the ion exchange between protons between the membrane and sodium ions. The solution was titrated with NaOH to the equivalence point [4].
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CURRENT TRENDS IN THE USE OF SOLAR ENERGY

CURRENT TRENDS IN THE USE OF SOLAR ENERGY

Most solar dryers developed are designed for specific products or class of products. Vegetables such as chilli, cassava, onion, radish, ginger, peas, corn, mushroom, tamarind and coconut, and fruits such as mango, apple, pineapple, banana, grapes, prunes. Selection of a solar dryer for a particular food product is determined by quality requirements, product characteristics and economic factors (Fadhel et al., 2011). Solar-assisted dryers are conventional dryers to which supplementary equipment is added to enable a significant proportion of the thermal energy required for drying to be replaced by solar energy. In these types of dryer, a planned, and generally optimized drying process can be achieved to obtain superior product quality and good economic performance. Any influence of the weather conditions on product quality and on the performance of the dryer can be eliminated by using an independent energy source, if needed, and proper control facilities. The construction of the solar assisted dryers is relatively complex compared to other dryers. They usually consist of a solar collector, a fan, a heat storage system, a burner/heater, and a control system. They can handle large quantities and deliver good product quality (Fadhel et al., 2011).
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