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ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / This paper describes a telemetry system used in the Missouri S&T solar car, which competed in the American Solar Challenge. The system monitors parameters of a number of the on-board electronic and mechanical systems, and also the activities of the vehicle driver. This data is transmitted to a lead vehicle, where the support team analyzes the performance in real-time to optimize the vehicle's performance. In previous vehicles the data was displayed using a LabVIEW based user interface. In this work we will describe a custom software solution, which provides the team with additional flexibility to display and analyze the data.

Faculty of Science School of Molecular and Cell Biology 9904041r lthompson@csir.co.za / The production of H2 was monitored using an automated, semi-continuously fed anaerobic fluidised bed bioreactor containing 2 facultatively anaerobic bacteria, Enterobacter cloacae (E. cloacae Ecl) and Citrobacter freundii (C. freundii Cf1). Shake flask tests using Endo formulation with modified C:N:P ratios, showed that a 334:28:5.6 ratio gave the highest attached counts of E. cloacae Ecl and C. freundii Cf1 in both single and binary species biofilms grown on granular activated carbon. Once the reactor had achieved steady state after 30 days using the modified C:N:P ratio, pH, redox potential, temperature, volatile fatty acids and the H2 production rate were monitored. The H2 production rate of 95 mmol H2 / (l x h) compared favourably with previous studies. Bacterial biofilms counts for both E. cloacae Ecl and C. freundii Cf1 remained high around 9.0 log cfu/g granular activated carbon, although biomass overgrowth could not be controlled in the reactor. The efficiency of converting sucrose into H2 was calculated at 20.5%. Therefore use of this technology to power a 5.0kW proton exchange fuel cell for a single rural household is currently not feasible due to the high organic load required. Pooling of wastewater generation capacity, improvement of bacterial strain selection and feed formulation, pH control, gas removal and purification are factors that need to be considered for future improvement of conversion efficiencies. Use of this technology would be most suited for industrial processes generating large volumes of wastewater high in carbohydrates. Alternatively, municipal wastewater treatment facilities could be converted into electricity generating facilities through the combination of this technology and proton exchange membrane fuel cells.

Piezoelectric energy harvesting is the process of taking an external mechanical input and converting it directly into electrical energy via the piezoelectric effect. To determine the power created by a piezoelectric energy harvester, a specific application with defined input and design constraints must first be chosen. The following thesis established a concept design of a hydrokinetic energy harvesting system, the piezoelectric artificial kelp (PAK), which uses piezoelectric materials to harvest coastal ocean waves while having a beneficial impact on the surrounding environment. The harvester design mimics the configuration of sea-kelp, a naturally occurring plant that anchors to the ocean floor and extends into the water column. Underwater currents caused by wave-action result in periodic oscillations in the kelp. In order to determine the average power generated by this design concept, predictive tools were devised that allowed for the determination of the optimized average power produced by the piezoelectric energy harvester. For a stiff energy harvester, the linear differential equations were analytically solved to find an equation for the average power generated as a function of design parameters. These equations were used to compare the effect on power output of the design configuration and piezoelectric material choice between a piezopolymer (PVDF) and a piezoceramic (PZT). The homogeneous bimorph was found to have the optimal design configuration and it was shown that a harvester constructed using PVDF would produce approximately 1.6 times as much power as one using PZT. For a flexible energy harvester, an iterative nonlinear solution technique using an assumed polynomial solution for the local curvature of the energy harvester was used to verify and extend the analytic solutions to large deflections. An energy harvester was built using off-the-shelf piezoelectric elements and tested in a wave tank facility to validate experimentally the voltage and average power predicted by the analytical solution. The iterative code showed the PAK harvester to produce volumetric power on the order of other energy harvesting concepts (17.8 micro [mu]W/cm³). Also, a full-scale PAK harvester approximately ten meters long in typical wave conditions was found to produce approximately one watt of power.

abstract: ABSTRACT As the use of photovoltaic (PV) modules in large power plants continues to increase globally, more studies on degradation, reliability, failure modes, and mechanisms of field aged modules are needed to predict module life expectancy based on accelerated lifetime testing of PV modules. In this work, a 26+ year old PV power plant in Phoenix, Arizona has been evaluated for performance, reliability, and durability. The PV power plant, called Solar One, is owned and operated by John F. Long's homeowners association. It is a 200 kWdc, standard test conditions (STC) rated power plant comprised of 4000 PV modules or frameless laminates, in 100 panel groups (rated at 175 kWac). The power plant is made of two center-tapped bipolar arrays, the north array and the south array. Due to a limited time frame to execute this large project, this work was performed by two masters students (Jonathan Belmont and Kolapo Olakonu) and the test results are presented in two masters theses. This thesis presents the results obtained on the south array and the other thesis presents the results obtained on the north array. Each of these two arrays is made of four sub arrays, the east sub arrays (positive and negative polarities) and the west sub arrays (positive and negative polarities), making up eight sub arrays. The evaluation and analyses of the power plant included in this thesis consists of: visual inspection, electrical performance measurements, and infrared thermography. A possible presence of potential induced degradation (PID) due to potential difference between ground and strings was also investigated. Some installation practices were also studied and found to contribute to the power loss observed in this investigation. The power output measured in 2011 for all eight sub arrays at STC is approximately 76 kWdc and represents a power loss of 62% (from 200 kW to 76 kW) over 26+ years. The 2011 measured power output for the four south sub arrays at STC is 39 kWdc and represents a power loss of 61% (from 100 kW to 39 kW) over 26+ years. Encapsulation browning and non-cell interconnect ribbon breakages were determined to be the primary causes for the power loss. / Dissertation/Thesis / M.S.Tech Technology 2012

abstract: Organic optoelectronic devices have remained a research topic of great interest over the past two decades, particularly in the development of efficient organic photovoltaics (OPV) and organic light emitting diodes (OLED). In order to improve the efficiency, stability, and materials variety for organic optoelectronic devices a number of emitting materials, absorbing materials, and charge transport materials were developed and employed in a device setting. Optical, electrical, and photophysical studies of the organic materials and their corresponding devices were thoroughly carried out. Two major approaches were taken to enhance the efficiency of small molecule based OPVs: developing material with higher open circuit voltages or improved device structures which increased short circuit current. To explore the factors affecting the open circuit voltage (VOC) in OPVs, molecular structures were modified to bring VOC closer to the effective bandgap, ∆EDA, which allowed the achievement of 1V VOC for a heterojunction of a select Ir complex with estimated exciton energy of only 1.55eV. Furthermore, the development of anode interfacial layer for exciton blocking and molecular templating provide a general approach for enhancing the short circuit current. Ultimately, a 5.8% PCE was achieved in a single heterojunction of C60 and a ZnPc material prepared in a simple, one step, solvent free, synthesis. OLEDs employing newly developed deep blue emitters based on cyclometalated complexes were demonstrated. Ultimately, a peak EQE of 24.8% and nearly perfect blue emission of (0.148,0.079) was achieved from PtON7dtb, which approaches the maximum attainable performance from a blue OLED. Furthermore, utilizing the excimer formation properties of square-planar Pt complexes, highly efficient and stable white devices employing a single emissive material were demonstrated. A peak EQE of over 20% for pure white color (0.33,0.33) and 80 CRI was achieved with the tridentate Pt complex, Pt-16. Furthermore, the development of a series of tetradentate Pt complexes yielded highly efficient and stable single doped white devices due to their halogen free tetradentate design. In addition to these benchmark achievements, the systematic molecular modification of both emissive and absorbing materials provides valuable structure-property relationship information that should help guide further developments in the field. / Dissertation/Thesis / Ph.D. Materials Science and Engineering 2014

Este trabalho aborda diversas implicações de ordem tecnológica, ambiental e social relacionados ao uso de carvão vegetal nos pólos guseiros. Através de coleta de dados em publicações técnicas, visitas a centros de tecnologia guseira e entrevistas com especialistas da área, foram levantadas as informações que serviram de base à elaboração deste trabalho. A análise e interpretação dos resultados obtidos mostram que a manutenção da produção de ferro-gusa depende do contínuo fornecimento de carvão vegetal, como termo-redutor de boa capacidade calorífica, preço baixo e fácil acesso. Todavia, nas condições atuais, o suprimento de carvão vegetal à indústria está relacionado à exploração intensiva de florestas nativas e uma correspondente falta de áreas reflorestadas capazes de suprir a demanda de lenha para carvoejamento. Além do carvão vegetal, outros insumos também podem ser usados na redução do minério de ferro: o gás natural (na produção integrada de aço) o carvão de coco de babaçu, o carvão vegetal de espécies nativas da Amazônia e mesmo o carvão mineral. Estes insumos, entretanto, apresentam problemas ainda não totalmente quantificados, como suprimento, tecnologia adequada de uso e custos de exploração. O uso intensivo de carvão vegetal se baseia na existência de uma rede de carvoejadores e fornos, que operam num ritmo de trabalho intenso (às vezes cerca de quinze horas por dia), baixa remuneração por madeira carvoejada (meio dólar por metro cúbico de carvão vegetal) e falta de seguridade social. De modo geral, os produtos de gusa pouco consideram o uso de carvão de florestas plantadas, pois admitem que um carvão de maior custo, constituir-se-ia em ameaça à própria continuação da produção de ferro-gusa. / The aim of this work is to discuss implications technological, environmentally and social limitations of the pig-iron´s production using charcoal. Through technical papers, technical visits to research centers and interview with experts, a data basis was collected to produce this work. The analysis of data showed that: the continuity of pig-iron making depends on continuos supply of charcoal, at low cost, with good heat capacity, and with easy acess. However, under current conditions, the charcoal supply to industry is depending of a intensive exploration of native forest. At the same time, there is a lack of land suitablefor reforestation to provide wood to renewable charcoal making. Nevertheless, there are several resources that can be used to reduce the iron ore: charcoal of babassu coconut, charcoal of native amazonic trees, natural gas (integrated plants) and even coal. Some of them are candidates to replace the charcoal, but further technological, infrastructural and economic developments are still required. The intensive utilization of charcoal by siderurgy is based in a network of kilns and charcoal makers working under extreme conditions (indeed, some work fifteen hours per day), they have no social security and extremely low wages (some receive only half a dollar per cubic metre of charcoal). In general, pig-iron´s makers do not consider the use of charcoal from forested wood, because its higher cost may challenge the viability of pig-iron production.

A vinhaça da cana-de-açúcar constitui-se no principal resíduo líquido gerado pelo setor sucro-alcooleiro e, face aos enormes volumes produzidos , os problemas decorrentes de seu armazenamento e disposição o final passaram a constituir nos últimos tempos num grande desafio a técnicos envolvidos com essa questão. Este estudo tem por objetivo apresentar uma alternativa de aproveitamento desse resíduo, Aquelas tradicionalmente conhecidas no meio alcooleiro, por .intermédio do tratamento e transformação da vinhaça em biogás e sua utilização na geração de eletricidade. Para tanto, adotou-se a tecnologia de digestão anaeróbia de alta eficiência através de digestores de fluxo ascendente para a produção de biogás e, uma vez purificado, o aproveitamento desse gás em motores e turbinas adequadas a esse tipo de combustíve1, conforme a literatura consultada. No sentido de avaliar a viabilidade prática deste trabalho, optou-se pela elaboração de um estudo de caso, no qual foi dimensionada uma destilaria hipotética de \'cerca de 150.000 litros de álcool/dia, gerando um volume de cerca de 1.800.000 litros de vinhaça/dia. Por meio desta simulação, foram analisados os aspéctos técnicos e econômicos envolvidos, possibilitando assim, uma apreciação crítica e realista do estudo proposto. / The vinasse of sugar-cane represents the main liquid residue produced by the sugar-alcohol sector and, in view of the enormous volumes produced, the problems related to its storage and final disposal came to pose a great challenge to the technical people involved in this matter these last few years. This study aims to present an alternative for the exploitation of this residue, to these traditionally employed in the alcohol production industry, based on the treatment and transformation of vinasse to biogas, and its subsequent utilization in eletric generation. In this context the technology of high efficiency anaerobic digestion using up-flow anaerobic digestors for biogas production was adapted. Once purified, the biogas produced can be utilized in engines and turbines specially adapted for this fuel, as evinced in the literature consulted. With a view to evaluate the pratical feasibility of this work, the elaboration of a case study was selected, in which a hypothetical distillery with a capacity of about 150.000 litres of alcohol/day, would generate a volume of about 1.800.000 litres of vinasse/day. By means of this simulation, the technical and economic aspects involved were analyzed, thus making possible a critical and realistic appreciation of the study proposed.

abstract: The ability to shift the photovoltaic (PV) power curve and make the energy accessible during peak hours can be accomplished through pairing solar PV with energy storage technologies. A prototype hybrid air conditioning system (HACS), built under supervision of project head Patrick Phelan, consists of PV modules running a DC compressor that operates a conventional HVAC system paired with a second evaporator submerged within a thermal storage tank. The thermal storage is a 0.284m3 or 75 gallon freezer filled with Cryogel balls, submerged in a weak glycol solution. It is paired with its own separate air handler, circulating the glycol solution. The refrigerant flow is controlled by solenoid valves that are electrically connected to a high and low temperature thermostat. During daylight hours, the PV modules run the DC compressor. The refrigerant flow is directed to the conventional HVAC air handler when cooling is needed. Once the desired room temperature is met, refrigerant flow is diverted to the thermal storage, storing excess PV power. During peak energy demand hours, the system uses only small amounts of grid power to pump the glycol solution through the air handler (note the compressor is off), allowing for money and energy savings. The conventional HVAC unit can be scaled down, since during times of large cooling demands the glycol air handler can be operated in parallel with the conventional HVAC unit. Four major test scenarios were drawn up in order to fully comprehend the performance characteristics of the HACS. Upon initial running of the system, ice was produced and the thermal storage was charged. A simple test run consisting of discharging the thermal storage, initially ~¼ frozen, was performed. The glycol air handler ran for 6 hours and the initial cooling power was 4.5 kW. This initial test was significant, since greater than 3.5 kW of cooling power was produced for 3 hours, thus demonstrating the concept of energy storage and recovery. / Dissertation/Thesis / M.S. Mechanical Engineering 2012

Vykstant intensyviai pasaulio ekonomikos plėtrai, nuolat auga ir energijos vartojimo mastai. Labiausiai naudojamų energijos šaltinių, ypač naftos bei dujų, atsargos yra ribotos ir nuolat senka. Ekonominė priklausomybė nuo energijos išteklių tiekėjų – energijos išteklių stokojančių šalių problema. Dar viena problema – neigiama organinio kuro deginimo įtaka klimato kaitai. Vienas iš ilgalaikių Lietuvos darnaus vystymosi strategijos uždavinių – skatinti, kad atsinaujinančiųjų energijos išteklių naudojimas energetikoje ir transporte nuolat didėtų ir iki 2020 metų sudarytų ne mažiau kaip 15 procentų bendro pirminės energijos balanso. Darbo tikslas – atskleisti alternatyvių energijos šaltinių panaudojimo skatinimo galimybes Lietuvoje. Uždaviniai: 1) išnagrinėti alternatyvių energijos šaltinių panaudojimo skatinimo teorinius aspektus; 2) išanalizuoti Lietuvoje bei užsienyje atliktus tyrimus bei empirinius duomenis atsinaujinančių energijos išteklių panaudojimo skatinimo srityje; 3) parengti empirinio tyrimo, įvertinančio alternatyvių energijos išteklių skatinimo priemonių efektyvumą Lietuvoje, metodologiją; 4) pritaikyti parengtą tyrimo metodologiją ir įvertinti alternatyvių energijos išteklių panaudojimo skatinimo priemonių efektyvumą; 5) pateikti alternatyvių energijos išteklių skatinimo Lietuvoje rekomendacijas. Buvo vykdoma ekspertų apklausa ir rezultatai parodė, kad atsinaujinančių energijos šaltinių skatinimas nėra pakankamas Lietuvoje. Supirkimo tarifai, ES struktūrinių fondų... [toliau žr. visą tekstą] / As world economy intensively develops, there is also seen a constant growth of energy consumption. Mostly used sources of energy, especially oil and gas resources are limited and constantly wasting. Economic dependence on energy suppliers is the problem of countries lacking in energy resources. Another problem is the negative impact of burning biogas on climate change. One of the long-term sustainable development strategies for Lithuania tasks is to promote the use of renewable energy resources in energetics and transport. The aim of work is to disclose the opportunities of alternative energy sources promotion for Lithuania. The objectives of work are: 1) to explore the theoretical aspects of alternative energy sources promotion; 2) to analyze Lithuanian and abroad studies and empirical data for renewable energy promotion; 3) to prepare the methodology of empirical study evaluating the efficiency of alternative energy resources promoting measures in Lithuania; 4) to adapt the methodology and assess the efficiency of alternative energy resources promoting measures; 5) to provide the recommendations how to promote alternative energy sources in Lithuania. It was conducted the survey of experts and the results showed that the promotion of renewables in Lithuania is not sufficient enough. Feed-in-tariffs, the promotion of the EU Structural Funds and tradable pollution permits can be identified as the best currently existing promotional measures. Currently operating tax incentives... [to full text]