El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / In Latin America, the lack of electricity has been a serious problem for over several years. To overcome this lack of supply in electricity supply, hydraulic energy is now being used in a greater proportion to fulfill the electricity needs in the rural areas. Investigations have been conducted to assess the environmental conditions of these rural areas to optimize the functionality of turbines used for hydraulic energy generation. However, there are very few focused on turbines of less than 0.5 kW generation. The proposed study aims to analyze the positioning of the blades of the cross-flow turbines and designing an electric generation system for rural dwellings. A simulation of each evaluated design was performed, and the power generated from these turbines was calculated. The results show that the power outputs initially were high and stabilized at a value of approximately 180 W, hence satisfying the minimum demands of a rural house.

Recent years have seen a dramatic increase in first generation bio-fuel production, mainly driven by concerns of climate change and rising prices of transportation fossil fuels. Due to significant pressure on the few available food sources, second generation bio-fuels have entered the fray, as a sustainable alternative. This research‟s aim was to search for cellulolytic micro-organisms and enzymes from the gut of the dung beetle, Euoniticellus intermedius, (Coleoptera: Scarabaeida) that can be used in the production of second generation bio-fuels. Dung beetle larvae were dissected and the gut micro-flora cultured in cellulose medium. Bacterial growth and cellulase activity was monitored on a daily basis. DNA isolation was then done on the cellulose medium-cultured microbes and the isolated DNA cloned in E. coli. The clones were screened for cellulase activity using plate assays. A total of 7 colonies out of 160 screened colonies showed positive CMC (endo-β-1,4-glucanase) and MUC (cellobiohydrolase) activities. Sequencing of these positive colonies yielded mostly bacteria belonging to the Enterobacteriaceae family, most of which have not been previously reported to have cellulase activity. This study‟s findings prove that in addition to this dung beetle‟s gut being a fruitful source of microbial biodiversity, it is also a potential source of cellulolytic micro-organisms and enzyme activities that will aid the function and design of future bioreactors for the bio-fuel industry.

Organic Photovoltaic devices (OPV) are considered to be attractive candidates for clean and renewable energy source because of their potential for low cost of fabrication, easy processing, and their mechanical flexibility. The device efficiency of OPV cells are limited by several factors. Among them are: (i) donor-acceptor interface, (ii) morphology of the materials, (iii) electrode-organic semiconductor (OSC) interface and (iv) device architecture such as active material thickness and electrode separation. Although, the donor-acceptor interface has been studied in detail, the commonly prevalent vertical OPV device structure does not allow a good understanding of the other key issues as the vertical structure limits one of the electrode to be a transparent electrode as well as introducing inseparable relation between the electrodes separation and the active material thickness. In addition, it is also well known that the charge transport in OSC is anisotropic and the charge mobility is better in lateral direction rather than vertical direction. In order to address some of these issues, we fabricated OPV devices in a planar device structure where cathode and anode of dissimilar metals are in-plane with each other and their photovoltaic behaviors were studied. We used poly(3-hexylthiophene) and [6,6]- pheny1 C61-butyric acid methy1 ester (P3HT:PCBM) blend as an active material. In particular, we present a detailed study about the effects of the structural parameters such as the channel length, the active layer thickness, and the work function of the electrodes on the open circuit voltage (Voc), short circuit current (Isc), fill factor (FF) and the power conversion efficiency (PCE). In order to determine the suitable anode and cathode for the planar organic photovoltaic (P-OPV) structure, we first fabricated and measured organic field effect transistor (OFET) devices with different contacts and studied the effect of barrier height at the iv P3HT:PCBM/electrode interface on the device output and transport properties. The study showed a clear effect of varying the contact material on the charge injection mechanism and on the carriers mobilities. The results have also shown that Au with high hole mobility and on current in the p-channel can be used as an anode (holes extractor) in the P-OPV device while In, Cr, and Ti that showed a reasonable value of electron mobility can be good candidates for cathode (electron extractor). We also found that, Ag, Al, and Mg showed large barrier which resulted in large threshold voltage in the I-V curve making them undesired cathode materials in the P-OPV device. We then fabricated P-OPV devices with Au as an anode material and varied the cathode material to study the effect of the interface between the P3HT:PCBM layer and the cathode material. When Al, Mg, or Ag used as a cathode material no PV behavior was observed, while PV behavior was observed for In, Cr, and Ti cathode materials. The PV behavior and the characteristic parameters including Voc, Isc, FF and PCE were affected by varying the cathode material. The results have shown that the P-OPV device performance can be affected by the cathode material depending on the properties and the work function of the metal. We have also studied the effect of varying the P3HT:PCBM layer thickness at a fixed channel length for Cr and Ti cathode materials and Au as anode. While Voc and FF values do not change, Isc and PCE increase with increasing the layer thickness due to the increase of the light absorption and charges generation. Moreover, we studied the effect of varying the channel length at a fixed film thickness; and showed that the values of Isc and PCE increase with decreasing channel length while Voc and FF maintain the same value. In this thesis we will also present the results on experimentally defining and testing the illuminated area in the P-OPV device by using different measurement set-ups and different v electrodes patterns. The results prove that the illuminated area in the P-OPV device is the area enclosed between the two electrodes. Lastly, we will present the effect of the P3HT:PCBM ratio on the P-OPV device performance. We show that 1:2 ratio is the optimized ratio for the P-OPV device. The detailed results in this thesis show a potential opportunity to help improving and understanding the design of OPV device by understanding the effects of the device structural parameters.

No description available.

No description available.

No description available.

The success of wind power integration throughout Europe has been largely varied with some European countries showing large boosts in capacity compared to some which show none at all.  This Thesis looks at those countries that have been successful in order to determine which factors have led to this success and what if any lessons can be learned in order to assist other countries.  The countries studied make up the top three for total wind power capacity and top three for total capacity per capita.  The surrounding elements that affect wind power development are assessed and relevant trends are investigated and discussed.  Factors such as, support instruments and overall governance are discussed in detail with a number of trends being found.  Calculations were conducted developing an average mean annual percentage increase for total capacity which showed that countries with an undeveloped wind power industry switching to a form of quota system could show a boost to total capacity.  No evidence was found that suggested switching to or changing an existing feed in tariff system would result in a boost in installed capacity.  In assessing governance, a trend was discovered showing obligations and targets helped to drive boosts in capacity especially for the countries who implemented a quota system. Brining these two trends together it was determined that strong top level governance was required to actually kick start boosts in total capacity.  The use of combinations of support schemes is assessed and a trend determined that suggests that use a quota system as a primary support scheme is better suited to having tax incentives as a secondary with feed in tariff systems having financial support as a secondary system.  A plan for developing wind power in countries with undeveloped wind power industries is developed based on the trends identified within the Thesis.  This suggests that a switch to a quota system combined with strong EU and national Governance could help to boost capacity to a point at which time a switch to a form of FIT would be beneficial to build on this steady base.

The deployment of renewable energy (RE) technologies for electricity generation is a central element of the European energy and climate strategy and was laid down in binding targets on EU-level. The actual RE technology diffusion is, however, shaped by the framework conditions and support measures implemented in the individual EU Member States. This dissertation aims at contributing to a more integrated view of the influencing factors (determinants) for the deployment of RE technologies. To this end, a conceptual framework is drawn up to assess the boundary conditions for RE diffusion from the RE developer’s perspective. The framework is operationalised using a composite indicator (CI) approach and applied in a diffusion model to allow the anticipation of possible future technology deployment. The thesis concentrates on two mainstream RE technologies, namely onshore wind and non-residential PV, and focuses on European countries. Within the analysis, particular emphasis is placed on providing a holistic assessment of the impact of economic and non-economic determinants on the diffusion of RE technologies at national level. The assessment aims at understanding RE developers’ preferences and rationalities regarding the overall framework conditions for RE deployment in order to identify the drivers for and barriers to technological change and to facilitate efficient policy design and regulatory transformation. The most relevant diffusion determinants from the viewpoint of RE project developers are identified through literature research and moderated expert workshops. The relative relevance of the determinants in the diffusion process is then assessed based on an EU-wide questionnaire that resulted in the collection of >200 datasets. Building on this broad empirical basis, a composite indicator (CI) is developed for the diffusion of non-residential PV and wind onshore. The CI provides a transparent framework for the quantification of the diffusion determinants and allows an evaluation and benchmarking of national RE frameworks. In a further step, the CI is integrated in a diffusion model which enables projections of possible future market developments under different configurations of the national RE framework. This modelling approach applies and further develops established logistic models of technology diffusion. The overall approach is validated by applying it to three case study countries: Germany, Spain and the United Kingdom. Data collection in these case study countries involved, among others, semi-structured interviews with 31 RE experts. The different regulatory framework conditions in the three countries lead to 3 different CI results and projected technology diffusion. The results verify the robustness of the approach and the applicability of the concept to different national contexts. The findings of this thesis contribute to the methodological and empirical basis for understanding and modelling technology diffusion processes in general and RE technology diffusion in particular. The approach developed in this thesis further improves the scientific basis for the evaluation of RE support policies and can contribute to RE targets being achieved in an efficient and sustainable way.

Governments and utility organizations around the world have mandated and provided incentives for new distributed renewable energy generation (DREG) capacity, and market projections indicate strong growth in distributed renewable energy generation installations in the coming years. New distributed renewable energy generation utilities, by definition, will be primarily located in built environments near consumers; these utilities are often planned and designed by landscape architects, yet no evidence-based, distributed renewable energy generation research is explicitly done by landscape architects or recognizes the role landscape architects play in planning and designing these spaces. The research and analysis provided by this study indicates that distributed renewable energy generation lacks a strong foundation as an independent concept which could benefit from clear broad phraseology linked to organized sub-terms/phrases for specific forms of DREG, that there has been some research done on topics familiar to landscape architects, that more needs to be done to meet important research questions and recommendations already posed, and that landscape architects are positioned to contribute to future distributed renewable energy generation research.

This paper presents the role of alternative energy technologies in displacing fossil fuels as the world's primary energy source. To that end, a CAPM-GARCH multi-factor market model is used to investigate the relationship between returns on oil and alternative energy stocks. Results show that an increase in oil prices and the broad market have a statistically significant and positive impact on alternative energy stock returns. Furthermore, the alternative energy sector is substantially more risky than the broad market but has the potential for higher returns. This highlights the infancy and inherently risky nature of the alternative energy sector today, but demonstrates the potential for substantial future investment gain as alternative energy technologies become more mature and widely available. Interestingly, estimation of the alternative energy index model indicated the presence of abnormal returns which was not the case for the solar index model, implying that the abnormal returns were generated from a different sectoral component of the alternative energy index.