No description available.

A annual nergy production analysis was undertaken to compare wind resources and annual energy production as estimated by WAsP and Windsim. Nordex Sverige AB has designed a wind farm with the help of WAsP and this study will involve the examination of this site with Windsim. Two site formations are of interest, one with the same class of turbine and one with a mix of two turbine types. The study is interested in the effect on annual energy production as estimated by the different software of employing a hybrid layout using wind turbines of different height.The results showed that whilst initial estimations of total energy production without wake losses appear very similar between WAsP and Windsim the ways in which the software are treating individual turbines within the planned farm can be quite different because of different physics. The analysis of the „hybrid‟ turbine layout showed significant increases in estimated annual energy production when a turbine with a higher tower and larger rotor diameter was used in a hybrid arrangement. Estimated annual energy losses on the turbines that were not changed in favour of a larger turbine were small. However, no great benefit in estimated turbine efficiency was achieved through the mixing of turbine types with different hub heights. The gains in annual energy production estimated by both software are however significant with increased production of 18 % across the entire farm when comparing the „hybrid‟ layout to a farm based on only the smaller of the two turbine types.

<p>This project considers an evaluation of a potential site for a small hydropower plant located in the BioBio north irrigation system, Chile. The purpose was to analyze the potential and constraints in harnessing the energy of an existing infrastructure of irrigation canals for electrical production. The site was analyzed technically, economically and managerially. Before this project nothing was done and therefore the investigations are a main part of the project. A preliminary design for the plant was proposed and the project was named the Minicentral Quillaileo-Mininco.</p><p>Investigations showed a flow variation of 1.62-2.2 m³ per second and a gross head of 44.3 meters. Evaluation gave a possible capacity of 840 kW producing 5 800 MWh annually. Appropriate electromechanical equipment is a Francis turbine with a diameter of 0.5 meter directly coupled to a 1000 rpm synchronous generator. The penstock recommended is a DN 1200 Flowtite GRP. The station is to be fully automatic and connected to the national grid.</p><p>The revenue is based on analysis of the past three year’s electrical market. The costs are based on budget proposals, statistical values and local comparisons. The economical analysis, based on a discount rate of 12% and life span of 35 years, gives a positive cash flow within eight years and a simple payback period of 5 years. The project will have a NPV value of 444 900 USD, IRR 14.70% and B/C of 1.2. Cost per kW will be 2 980 USD. The project is recommended to be further developed.</p>

This project considers an evaluation of a potential site for a small hydropower plant located in the BioBio north irrigation system, Chile. The purpose was to analyze the potential and constraints in harnessing the energy of an existing infrastructure of irrigation canals for electrical production. The site was analyzed technically, economically and managerially. Before this project nothing was done and therefore the investigations are a main part of the project. A preliminary design for the plant was proposed and the project was named the Minicentral Quillaileo-Mininco. Investigations showed a flow variation of 1.62-2.2 m3 per second and a gross head of 44.3 meters. Evaluation gave a possible capacity of 840 kW producing 5 800 MWh annually. Appropriate electromechanical equipment is a Francis turbine with a diameter of 0.5 meter directly coupled to a 1000 rpm synchronous generator. The penstock recommended is a DN 1200 Flowtite GRP. The station is to be fully automatic and connected to the national grid. The revenue is based on analysis of the past three year’s electrical market. The costs are based on budget proposals, statistical values and local comparisons. The economical analysis, based on a discount rate of 12% and life span of 35 years, gives a positive cash flow within eight years and a simple payback period of 5 years. The project will have a NPV value of 444 900 USD, IRR 14.70% and B/C of 1.2. Cost per kW will be 2 980 USD. The project is recommended to be further developed.

Σκοπός της παρούσας διπλωματικής εργασίας είναι η μελέτη των κυψελών καυσίμου ως εναλλακτική πηγή τάσεως. Ο λόγος για τον οποίον έχει στραφεί η έρευνα προς τις ανανεώσιμες πηγές ενέργειας είναι αφενός η αύξηση των ενεργειακών απαιτήσεων των κοινωνιών σε συνδυασμό με τη μείωση των διαθέσιμων ορυκτών καυσίμων και αφετέρου η μόλυνση του περιβάλλοντος που έχει προέλθει από ρύπους όπως είναι το διοξείδιο του άνθρακα. Οι πιο ευρέως χρησιμοποιούμενες ανανεώσιμες πηγές ενέργειας σήμερα είναι η ηλιακή, η αιολική και η υδροηλεκτρική. Τα τελευταία χρόνια αποκτά ιδιαίτερο ενδιαφέρον και η τεχνολογία του υδρογόνου λόγω κάποιων πλεονεκτημάτων που διαθέτει, όπως η μεγάλη ικανότητα παραγωγής ενέργειας ανά μονάδα βάρους (σχεδόν τριπλάσια από την αντίστοιχη ικανότητα παραγωγής ενέργειας της βενζίνης), η υψηλή αποδοτικότητα και αξιοπιστία καθώς και οι μηδενικές επιπτώσεις για το περιβάλλον. Βέβαια, υπάρχουν και αρκετά μειονεκτήματα που σχετίζονται με τη σχετικά πρόσφατη στροφή της έρευνας προς αυτή την κατεύθυνση (ακριβές διατάξεις παραγωγής και κατανάλωσης υδρογόνου , μη εγκατεστημένο δίκτυο διανομής και δυσκολίες στην αποθήκευση του υδρογόνου). Στη συνέχεια αναλύεται το θεωρητικό υπόβαθρο της τεχνολογίας αυτής και παρουσιάζονται μέθοδοι βελτίωσης της απόδοσής της. Αρχικά, γίνεται μια μικρή ιστορική αναδρομή σε αυτή τη τεχνολογία προκειμένου να γίνει σαφές πως οδηγηθήκαμε στη σκέψη παραγωγής ενέργειας μέσω της αντίδρασης του υδρογόνου και του οξυγόνου. Αναλύονται τα πλεονεκτήματα που έχουν οι κυψέλες καυσίμου έναντι τόσο των μηχανών εσωτερικής καύσης όσο και έναντι των μπαταριών και παρουσιάζονται όλοι οι εμπορικά διαθέσιμοι τύποι κελιών καυσίμου. Ιδιαίτερη έμφαση στη διπλωματική εργασία δίνεται στη δομή και στην αρχή λειτουργίας των κυψελών καυσίμου τύπου μεμβράνης ανταλλαγής πρωτονίων λόγω της ευελιξίας και της ποικιλίας των εφαρμογών που μπορούν να υποστηρίξουν. Οι κυψέλες καυσίμου αυτού του είδους παρουσιάζουν χαμηλή θερμοκρασία λειτουργίας, χαμηλούς χρόνους εκκίνησης, γρήγορη απόκριση στις μεταβολές φορτίου και μεγάλη ανθεκτικότητα. Εν συνεχεία παρουσιάζεται η απόδειξη, από την οποία προκύπτει η μέγιστη θεωρητική τάση(1.229V) ενός κελιού καυσίμου, οι μηχανισμοί που προκαλούν πτώση τάσης από τη μέγιστη θεωρητική τιμή καθώς και το ισοδύναμο ηλεκτρικό κύκλωμα. Η προσομοίωση και μοντελοποίηση των κυψελών, που ακολουθεί, κατέχει σημαντική θέση στην ανάλυση και στην πρόβλεψη της ηλεκτρικής συμπεριφοράς τους καθώς αυτές ενσωματώνονται σε συστήματα ισχύος. Παρουσιάζονται διαγράμματα που προέκυψαν από τη μοντελοποίηση και φανερώνουν πως εξαρτάται η τάση του κελιού, οι απώλειες ενεργοποίησης, οι ωμικές απώλειες και η ισχύς εξόδου συναρτήσει τόσο της πυκνότητας ρεύματος όσο και της θερμοκρασίας. Ιδιαίτερη αναφορά γίνεται στις 3 διαφορετικές περιοχές της χαρακτηριστικής τάσεως-ρεύματος. Μέσα από τις προκύπτουσες καμπύλες γίνεται σαφές το εξής. Οι απώλειες ενεργοποίησης έχουν επίδραση μόνο στις χαμηλές πυκνότητες ρεύματος και για την θερμοκρασία λειτουργίας είναι της τάξεως των 0.48 V. Πράγματι, με το σχεδιασθέν μοντέλο βλέπουμε ότι η τάση του κελιού για χαμηλές πυκνότητες ρεύματος είναι της τάξεως του 0.7 V, δηλαδή η μέγιστη θεωρητική τάση μειούμενη κατά τις απώλειες ενεργοποίησης. Οι ωμικές απώλειες έχουν επίδραση για μέσες πυκνότητες ρεύματος και προσομοιώνονται με μια ωμική αντίσταση, η οποία περιλαμβάνει την αντίσταση των ηλεκτροδίων στην κίνηση των ηλεκτρονίων, την αντίσταση της μεμβράνης στην κίνηση των κατιόντων και την αντίσταση που παρουσιάζεται στην επιφάνεια επαφής ηλεκτροδίου και μεμβράνης. Η εξάρτηση των ωμικών απωλειών συναρτήσει της πυκνότητας ρεύματος είναι γραμμική, αυξάνονται συναρτήσει της θερμοκρασίας και επίσης και με την αύξηση του πάχους του ηλεκτρολύτη, όπως προέκυψαν από τη μοντελοποίηση της κυψέλης. Λόγω του ότι η προκύπτουσα τάση είναι της τάξης του 0.5-1 V, γίνεται αναγκαία η σύνδεση πολλών κελιών σε σειρά. Ο πιο διαδεδομένος τρόπος, για να μειωθούν οι απώλειες στις συνδέσεις, είναι με τη χρήση διπολικών πλακών. Ένα ενδιαφέρον ζήτημα που εξετάζεται είναι η δυναμική απόκριση των μοντέλων αυτών, η οποία προσομοιώνεται ηλεκτρονικά. Η μελέτη που έχει γίνει αποσκοπεί στη βελτίωση της απόδοσης, στη ταχύτερη απόκριση στις δυναμικές μεταβολές και κυρίως στον τρόπο με τον οποίον θα μπορέσει μια διάταξη κυψέλης καυσίμου να τροφοδοτήσει πραγματικά φορτία, τα οποία απαιτούν σταθερή τάση. Οι κυψέλες δίνουν συνεχή τάση μη καθορισμένης όμως τιμής. Έτσι, προκειμένου να συνδεθεί ένα φορτίο πρέπει αυτή η μη καθορισμένη τάση εξόδου να ενισχυθεί και να κρατηθεί σταθερή σε μία επιθυμητή τιμή. Η ενίσχυση επιτυγχάνεται με τη τοποθέτηση ενός μετατροπέα τύπου boost στην έξοδο της κυψέλης. Η σταθεροποίηση επιτυγχάνεται μέσω ενός κυκλώματος ανατροφοδότησης, το οποίο εντοπίζει τη διαφορά ανάμεσα στη τάση εξόδου του μετατροπέα και στη τάση αναφοράς και καθορίζει αναλόγως τη παλμοδότηση του ημιαγωγικού στοιχείου του μετατροπέα. Τα στοιχεία του μετατροπέα επιλέγονται, ώστε να λειτουργεί σε κατάσταση συνεχούς αγωγής. Αναλύεται η λειτουργία του μετατροπέα ανύψωσης τάσης και εξηγείται πλήρως ο τρόπος με τον οποίον σχεδιάστηκε η ανατροφοδότηση στον μετατροπέα. Παρατίθεται η απόκριση του συστήματός μας, όταν στην έξοδο έχουμε καθαρά ωμικό, επαγωγικό και χωρητικό φορτίο. Παρατηρείται ότι σε κάθε περίπτωση ο μετατροπέας διατηρεί σταθερή τη τιμή της τάσης στην επιθυμητή τιμή. Επίσης, παρατίθεται η απόκριση του μετατροπέα σε φορτίο που σχεδιάστηκε, έτσι ώστε να μεταβάλλεται κάθε 3 δευτερόλεπτα. Και σε αυτήν την περίπτωση, ο μετατροπέας μετά το πέρας των μεταβατικών φαινομένων καταφέρνει να διατηρήσει σταθερή τη τιμή της τάσεως εξόδου. Στο τελευταίο μέρος της διπλωματικής εργασίας, παρουσιάζεται η πειραματική διαδικασία που πραγματοποιήθηκε σε μια συστοιχία κυψέλων καυσίμου τύπου μεμβράνης ανταλλαγής πρωτονίων ισχύος 1.2kW. Περιγράφεται αναλυτικά ο τρόπος με τον οποίον λειτουργεί η χρησιμοποιηθείσα κυψέλη υδρογόνου. Παρουσιάζονται οι διαδικασίες που απαιτούνται για την έναρξη και τον τερματισμό της, οι επιμέρους μονάδες που απαιτούνται για την τροφοδότηση της κυψέλης με τα αντιδρώντα καθώς και οι μηχανισμοί ασφαλείας που υπάρχουν προκειμένου να αποτραπούν επικίνδυνες καταστάσεις για την ομαλή λειτουργία της κυψέλης. Επίσης αναλύονται τα βήματα που ακολουθήθηκαν για να προκύψουν οι χαρακτηριστικές τάσεως-ρεύματος και ισχύος-ρεύματος. Σε κοινά διαγράμματα συγκρίνονται με τις αντίστοιχες καμπύλες που αναφέρει το φυλλάδιο των κατασκευαστών. Σε άλλο πείραμα παρουσιάζεται η εξάρτηση της τάσεως της κυψέλης από τη θερμοκρασία και επιβεβαιώνεται η θεωρία, η οποία αναφέρει μείωση της τάσεως εξόδου, καθώς αυξάνει η θερμοκρασία. Η μεταβολή της τάσεως παρατηρείται εντονότερα στην ωμική περιοχή, εκεί όπου επικρατούν οι ωμικές απώλειες και οι οποίες είναι ανάλογες με την πυκνότητα του ρεύματος. Ακολούθως, αναλύεται η μέθοδος βάσει της οποίας μπορεί να υπολογιστεί η απόδοση της κυψέλης καυσίμου. Πρόκειται για περίπλοκο μηχανισμό, αφού η είσοδος του συστήματος είναι χημική ενέργεια και έξοδος ηλεκτρική ενέργεια. Με βάση αυτό το μηχανισμό, παρουσιάζεται η σχέση της απόδοσης με το ρεύμα και τη θερμοκρασία, όπως προέκυψε από τη πειραματική διαδικασία. Τέλος, παρουσιάζονται μέσω διαγράμματος οι χρόνοι που χρειάζεται η τάση για να σταθεροποιηθεί κατά τη σύνδεση και την αποσύνδεση του φορτίου και αναλύεται ο μηχανισμός εκείνος, ο οποίος συμβάλλει στον μη μηδενικό χρόνο απόκρισης των κυψελών καυσίμου. / The aim of the present essay is the study of fuel cells as an alternative source of voltage. The reason why the research has turned to the renewable sources of energy is not only the increase of energy requirements of societies but also the reduction of available mining fuels and the air pollution. The more widely used renewable sources of energy today are solar and hydroelectric. The last years, the technology of hydrogen acquires particular interesting, because of certain advantages such as the big faculty of production of energy per unit of weight, the high efficiency and reliability as well as the null repercussions for the environment. Of course, there are also disadvantages that are related to the recent turn of research to this direction (expensive provisions of production and consumption of hydrogen, not installed network of distribution and difficulties in the storage of hydrogen). The analysis includes apart from the theoretical background of this technology and presentation of methods of improvement of the efficiency. Particular accent in this essay is given in the operation of fuel cells of type of membrane exchange protons due to the flexibility and the variety of applications that they can support. This type of cells operates at low temperature, responds fast in the start and in load changes and has high resistibility. Then, the structure and the operation of a PEM fuel cell are being represented. It is represented the background for the highest theoretical cell voltage, the reasons why the voltage does not remain constant at this value of voltage and an equivalent electrical circuit. The simulation and modeling of cells, that follows, plays important role in the analysis and in the forecast of their electric behavior, as they are incorporated in power systems. Firstly, the history behind this technology is presented. Advantages and disadvantages of fuel cells and all types of available fuel cells are presented. In this essay, the structure of a PEM Fuel cell and the way it operates is analyzed. This type of fuel cell operates at low temperatures and as a result, it starts quickly and responds fast at load changes. After this, it is being proved that the maximum theoretical voltage of o stack is 1.229 V. The reasons why this value of voltage is inevitable and the equivalent electrical circuit are also being analyzed. Diagrams, that resulted from the modeling and show how cell voltage, activation losses and ohmic losses are depended on current density and temperature, are presented. The activation losses have impact only on low current densities. Their value is around 0.48 V at the operating temperature of 650C. The diagram that presents the polarization curve evaluates the previous sentence, as the voltage at open circuit is about 0.7V (1.229V minus the activation losses). The ohmic losses have impact on current densities between 0.01 and 0.1 A/cm2. They are being modeled by an ohmic resistance, which includes the resistance of the electrodes during the flow of the electrons and the resistance of the membrane during the flow of the ions. The ohmic losses are proportional to the current density and increase, as the temperature increases. These came out from a simulation in Matlab. Because the voltage is around 0.5-1 V, the connection of many cells in series becomes necessary. In order to reduce the losses in the connections, bipolar plates are used. Particular report at the simulation becomes in the dynamic response of this model. The study aims in the improvement of efficiency, in the faster response in the dynamic changes and mainly in the way that the stack has to be connected in order to supply energy in real loads that require constant voltage. The stack produces a not determined dc voltage. Thus, this undetermined voltage should be strengthened and kept constant in a desirable value. The increase is achieved with the placement of a boost converter in the output of stack. The stabilization is achieved via a circuit of feedback, which locates the difference between the output voltage of the converter and the reference value and determines the duty cycle. The parameters of the converter are chosen in order to have continuous conduction mode. The operation of the converter is analyzed and the way the feedback operates is totally explained. Diagrams that show the response of the converter, when the load is resistance, an inductor and a capacitor are represented. In every situation, the voltage remains constant at the value of reference voltage. The response in a load that changes every 3 seconds is also presented. The voltage also remains constant at 80V. Finally, the experimental process, that took place in a fuel cell of type of membrane exchange protons 1,2kW, is presented. The way this stack operates is analytically described. The processes that are required for the beginning and the finish, the individual units that are required for the feed-in of oxygen and hydrogen and the mechanisms of safety that exist in order to avoid dangerous situations are presented. Also, the characteristics of voltage and power as function of current are presented. In common diagrams, they are being compared with the equivalent diagrams that are presented by the manufacturer. The dependence of stack voltage on the temperature is being experimented and is confirmed with the theory, which reports reduction of voltage, as the temperature increases. This dependence becomes stronger at the ohmic region, because the ohmic losses are proportional to current density. Moreover, the method we can follow in order to calculate the efficiency of the stack is analyzed. It is a complex mechanism, because the entry of the system is chemical energy and the exit is electrical energy. With base this mechanism, the relationship of efficiency with the current and the temperature is presented, as it resulted from the experimental process. Finally, the stabilization times during the connection and disconnection of a load are presented via a diagram and the mechanism, which contributes in the not null time of response of stack, is analyzed.

The increase in energy demand boosted Brazil to seek new sources of energy to meet the growing demand of the country. And the use of planted forests for energy purposes has stood out as a promising alternative, for being a source of generating clean, renewable energy. Eucalyptus forests have been highlighted as the most planted in the world, for being the most productive. However, due to the need for increased productivity's survey was conducted in order to assess the effects of different water conditions on the growth and physiology of eucalyptus clonal seedlings, focusing on the production of biomass for energy generation. This research was developed in the greenhouse, in the laboratory of plant physiology and forest seedlings, in the center of Agrarian Sciences (ECSC) in the Universidade Federal de Alagoas (UFAL), between the months of July to November 2015, with 120-day trial period. Eucalyptus clonal seedlings were used. The seedlings have undergone a process of transplanting, which were cultivated for a period of 60 days for acclimatization. The experimental design was completely randomized design (DIC), the treatments were arranged in factorial 3 x 2 system consisting of three clonal seedlings (144, 1407 and u 865) and two water conditions 75% of field capacity and 100% of field capacity, with five repetitions. To accompany the growth were measured weekly variables (height, number of leaves and stem diameter of clonal seedlings). At the end of the experiment evaluated the production and dry matter allocation of parts areas and roots and root/shoot ratio. Also at the end of the experiment was evaluated the issue of chlorophyll a fluorescence, at noon (Fv/Fm and Yield) and the chlorophyll content in third leaf fully developed, using the portable light modulated Fluorômetro ... and SPAD and by biochemical method. The data were subjected to analysis of variance using the software Assistat, averages were compared with each other by Tukey test at 5% probability. It can be observed that the water condition 100% of field capacity occurred significant differences for all variables, growth and production and rental of biomass, there was also a reduction of the quantum efficiency of photosystem II,green intensity of leaves(Spad) readings and chlorophyll a, chlorophyll b, total chlorophyll and carotenoid. Showed that the water condition 75% of field capacity clonal seedlings developed better. The data indicates that the clone was i144 which had less tolerance for water condition 100% of field capacity, the clones and 1407 865 were those who had a higher tolerance for water condition 100% of field capacity. / O aumento da demanda energética impulsionou o Brasil a buscar novas fontes de energia, para suprir a crescente demanda do país. E a utilização de florestas plantadas para fins energéticos tem se destacado como uma alternativa promissora, por ser uma fonte geradora de energia limpa e renovável. As florestas de eucalipto têm sido evidenciadas como a mais plantada no mundo, por ser a mais produtiva. No entanto, em razão da necessidade do aumento da produtividade está pesquisa foi realizada objetivando avaliar os efeitos das diferentes condições hídricas no crescimento e na fisiologia das mudas clonais de eucalipto, tendo como foco a produção de biomassa para geração de energia. Esta pesquisa foi desenvolvida em casa de vegetação, no Laboratório de Fisiologia Vegetal e no setor de mudas florestais, no Centro de Ciências Agrárias (CECA), pertencente à Universidade Federal de Alagoas (UFAL), entre os meses de julho à novembro de 2015, com período experimental de 120 dias. Foram utilizadas mudas clonais de eucalipto. As mudas passaram por um processo de transplantio, as quais foram cultivadas por um período de 60 dias para aclimatização. O delineamento experimental foi inteiramente casualizado (DIC), os tratamentos foram arranjados no sistema fatorial 3x2 constituído de três mudas clonais (144, 1407 e vc 865) e duas condições hídricas 75% da capacidade de campo e 100% da capacidade de campo, com cinco repetições. Para acompanhar o crescimento foram mensuradas semanalmente as variáveis (altura, número de folhas e diâmetro do caule da mudas clonais). Ao final do experimento avaliou a produção e alocação da matéria seca das partes áreas e raízes e a relação raiz/parte aérea. Também no final do experimento foi avaliado a emissão de fluorescência da clorofila a, ao meio-dia (Fv/Fm e Yield) e o teor de clorofila na terceira folha completamente desenvolvida, utilizando-se o. Fluorômetro portátil de luz modulada e SPAD e pelo método bioquímico. Os dados foram submetidos à análise de variância utilizando o software Assistat, as médias foram comparadas entre si pelo teste de Tukey a 5% de probabilidade. Pode-se observar que na condição hídrica 100% da capacidade de campo ocorreram diferenças significativas para todas as variáveis de crescimento, e para produção e a locação de biomassa, houve também redução da eficiência quântica do fotossistema II, intensidade verde (Spad )e clorofila a, clorofila b, clorofila total e carotenoide. Evidenciou que a condição hídrica 75% da capacidade de campo as mudas clonais desenvolveram-se melhor. Os dados indicam que o clone i144 foi que teve menor tolerância à condição hídrica 100% da capacidade de campo, os clones 1407 e vc 865 foram os que tiveram maior tolerância à condição hídrica 100% da capacidade de campo.

>Magister Scientiae - MSc / As the demand for energy is constantly increasing, researchers are looking at various methods of energy production. Following the rise of solar energy becoming a major player, researchers are looking at kesterite materials, Cu2ZnSn(S,Se)4 (CZTS) for photovoltaic applications as they demonstrate many excellent characteristics making them highly suitable for use in thin-film solar cells. Consequently, there are major drawbacks of using kesterite materials for photovoltaic applications such as their point defects and secondary phases. Cerium and iron oxyselenides (Ce2O2Fe2OSe2) are a member of the chalcogenide family and by introducing this chalcogenide into the kesterite structure there would be an improvement in the semiconducting property of the kesterite material. The focus of this research is to dope the kesterite material with nanoscopic cerium and iron oxyselenides in order to reduce the band gap of the kesterite material, thereby improving its light absorption, thus, resulting in a more efficient photovoltaic effect.

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Planting woody biomass for energy production can be used as a mine reclamation procedure to satisfy the Surface Mining Control and Reclamation Act of 1977 (SMCRA) and provide renewable energy for the United States.  This study examines the economic viability of bioenergy production on previously mined lands using multiple hardwood species and treatments.  Five species were planted at two densities; one-half of the trees were fertilized in year two.  Height and diameter of the trees were measured annually for five years; the first three years by cooperating researchers at Virginia Tech, the last two years specifically for this report.  Current and predicted mass of the species, effects of planting density and fertilizer application, and the land expectation value (LEV) of each treatment were summarized.  A sensitivity analysis was conducted to determine how changes in production costs, stumpage price, rotation length, and interest rate affect the economic feasibility of bioenergy production.  Renewable energy and mine reclamation policies were investigated and it was determined that woody bioenergy can be planted as a mine reclamation procedure and may receive financial incentives.  Production cost appears to have the largest impact on LEV and is often the difference between positive and negative returns for the landowner.  The extra cost of fertilization and high density planting do not increase LEV; the unfertilized, low density treatments have the best LEV in all examined scenarios.  In general, bioenergy was found to be economically viable as a mine reclamation procedure only in limited circumstances.  In low cost, high price scenarios, bioenergy crops could have the potential to reforest both active and abandoned mine lands throughout southern Appalachia. / Master of Science

In the waste management system of Peru, there is a lot to fix, change and improve from households areas. In this report is presented why and how necessary is the construction of landfills to have an appropriate place to dispose the waste of the collection .At the same time, the report shows how profitable can be from social, economic and ecologic way, with the investment of treatment plants that use biogas from the landfills to produce energy. Differents solutions – vehicle fuel production, electricity generation etc – are discussed in light of the different economy, geography and social situation in three selected cases.