Programa educatiu. Energies renovables i ús eficient de l'energia. 'Programa educativo. Energías renovables y uso eficiente de la energía'.

Resumen tomado de la publicación. Descripción basada en el cuaderno del profesor

Sem??ntica l??xica i argumentaci?? : sobre les energies renovables

Resumen basado en el de la publicaci??n

Casa eficient energèticament

El present projecte té com objecte realitzar una casa que sigui eficient energèticament a partir d’una casa ja construïda, modificant així tot el que sigui necessari per poder aconseguir una millora del comportament bioclimàtic de la casa i una major independència dels subministraments de la xarxa pública (electricitat i gas). El projecte es divideix en tres fases clarament diferenciades: una primera consistent en realitzar una recerca dels sistemes constructius que fan que una casa funcioni millor i sigui més eficient a nivell energètic (façana ventilada, forjat sanitari, coberta enjardinada ,etc) i també consistent en realitzar un estudi dels sistemes o mètodes de producció d’energia més ecològics (energia solar, geotèrmia, energia eòlica, etc), que facin la casa més autònoma en quan a les energies i subministraments de la xarxa pública de distribució (electricitat i gas); una segona fase consistient en triar els sistemes constructius i de producció d’energia tenint en compte la informació obtinguda de la recerca inicial i aplicar aquests sobre una casa unifamiliar amb sistemes constructius i de producció d’energia tradicional (façana amb obra vista, calefacció amb caldera a gas i radiadors,etc) elegida a l’atzar; i una tercera i última fase consistent en fer un comparatiu econòmic entre el cost de construcció de la casa amb sistemes tradicionals i de la casa eficient. Després és farà una estimació de l’estalvi energètic d’una i de l’altra casa, i amb tot això es valorarà si són amortitzables les despeses que s’han realitzat per aconseguir aquests estalvis energètics

Fuentes renovables de energía en América Latina y el Caribe: situación y propuestas de políticas

Incluye Bibliografía

Allocation of GHG emissions in a paper mill, an application tool to reduce emissions

El sector de pasta i paper és considerat un dels set sectors industrials més intensius en consum energètic. La producció i consum d'electricitat i de vapor esdevenen les fonts majoritàries d'emissions de gasos d'efecte hivernacle en aquest sector industrial. Les fàbriques papereres poden assolir objectius de reducció d'emissions mitjançant reducció en origen (substitució de combustibles, introducció d'energies renovables) o bé a partir de mesures d'eficiència energètica en el propi procés. En aquest context, s'ha desenvolupat un mètode de distribució d'emissions que permet assignar a cada unitat d'operació del procés paperer, el seu grau de responsabilitat en emissions. També s'han avaluat diferents mètodes de càlcul de factors d'emissió de vapor i electricitat, tant per plantes de cogeneració com per sistemes individuals. A partir d'aquesta avaluació s'han proposat nous mètodes alternatius als analitzats. Aquests mètodes i els factors d'emissions s'han aplicat a dues fàbriques papereres catalanes.

Energías renovables en edificación: aplicación al abastecimiento de energía eléctrica y climatización

[ES]Este documento tiene el objeto de presentar el uso de las energías renovables en la edificación actual, para ello se analizaran las energías que hay en el mercado, sus beneficios y sus posibles aplicaciones en viviendas, naves industriales, polideportivos, centro comerciales, etc. Para lograr alcanzar todas estas competencias se hará mayor hincapié en el uso de estas nuevas tecnologías en abastecimientos de energía eléctrica y climatización, teniendo en cuenta que no todas las energías renovables son aplicables a la edificación y que no todas las energías tienen las mismas utilidades. El trabajo se lleva a cabo dentro de los trabajos de fin de grado de la escuela técnica superior de ingeniería de Bilbao (ETSIB), más concretamente se refiere al trabajo tipo TFG.3. El trabajo también consta de los apartados descargo de costes y planificación, donde se analiza el desglose de los gastos empleados para la realización de esta memoria y el tiempo elaboración para el mismo. Para concluir es añaden anexos, en los cuales se explican varias de las Normas que se manejan en la actualidad y también se incluyen algunos catálogos de productos comerciales y sus dispositivos para colocar en el edificio.

Evolución y transcendencia del sector de las energias renovables en España

Nowadays the energies that still prevail on a global scale as a source of generation of electricity are those that come from fossil resources. Nevertheless, in a few years the future of energy will center on renewable energies. Those countries that are not involved in their development will be at a clear disadvantage at economic level, since the electrical power is the base for the development of human society and the renewable energies are essential for its production. The present work has as a target to show, in a clear and concise form, the current situation of the sector of renewable energies in Spain. In addition, we present in a brief and summarised form, an aspect that has been essential in the development of the renewable energies in Spain is tackled. This is, the legislation on the matter as well as the development plans that Spain has carried out for its promotion. Finally, the study considers the compared situation of the sector of the renewable energies and of the energy sector in general in Spain in the context of the EU. IDIOMA: Ingles

Renewable energies Driven by Feed-on Tariffs. Photovoltaic vs Wind Energy Development in Spain

Although others regulations regarding feed-in tariffs for photovoltaics (PV) existed in Spain previously, the one that meant a paradigm change was the introduction in 2007 of law R.D.661/2007 which established a feed-in tariff of 41,75 cents/kWh if the installed capacity was greater than 100KWp and 44,04 cents/kWh if it was smaller. The high level of the subsidies together with the lack of a limit for the total installed capacity originates the well-known Spanish photovoltaic boom. In September 2008 the installed PV capacity accounted for 3.2GWp (while the official objective stated in the national renewable roadmap was only 400MWp). To avoid this situation a new law, R.D. 1578/2008, was proclaimed which established a decreasing feed-in tariff of 32 cents/kWh (for ground installations) and 34 cents/kWh (for rooftops) and it limited the annual installed capacity to 500MWp. Although it was successful in limiting the PV subsidies total costs, the successive and sudden changes in regulations resulted very harmful to the local PV industry. In this article, the strong influence of feed-in tariff in the development of PV installed capacity and market evolution in Spain will be analyzed in detail. In addition, a comparison with other subsidized technologies which installed capacity has had a smoother evolution, as wind energy, will be presented.

Electricity price forecasting accounting for renewable energies: optimal combined forecasts

Electricity price forecasting is an interesting problem for all the agents involved in electricity market operation. For instance, every profit maximisation strategy is based on the computation of accurate one-day-ahead forecasts, which is why electricity price forecasting has been a growing field of research in recent years. In addition, the increasing concern about environmental issues has led to a high penetration of renewable energies, particularly wind. In some European countries such as Spain, Germany and Denmark, renewable energy is having a deep impact on the local power markets. In this paper, we propose an optimal model from the perspective of forecasting accuracy, and it consists of a combination of several univariate and multivariate time series methods that account for the amount of energy produced with clean energies, particularly wind and hydro, which are the most relevant renewable energy sources in the Iberian Market. This market is used to illustrate the proposed methodology, as it is one of those markets in which wind power production is more relevant in terms of its percentage of the total demand, but of course our method can be applied to any other liberalised power market. As far as our contribution is concerned, first, the methodology proposed by García-Martos et al(2007 and 2012) is generalised twofold: we allow the incorporation of wind power production and hydro reservoirs, and we do not impose the restriction of using the same model for 24h. A computational experiment and a Design of Experiments (DOE) are performed for this purpose. Then, for those hours in which there are two or more models without statistically significant differences in terms of their forecasting accuracy, a combination of forecasts is proposed by weighting the best models(according to the DOE) and minimising the Mean Absolute Percentage Error (MAPE). The MAPE is the most popular accuracy metric for comparing electricity price forecasting models. We construct the combi nation of forecasts by solving several nonlinear optimisation problems that allow computation of the optimal weights for building the combination of forecasts. The results are obtained by a large computational experiment that entails calculating out-of-sample forecasts for every hour in every day in the period from January 2007 to Decem ber 2009. In addition, to reinforce the value of our methodology, we compare our results with those that appear in recent published works in the field. This comparison shows the superiority of our methodology in terms of forecasting accuracy.

Formation energies of low-indexed surfaces of tin dioxide terminated by nonmetals

The surface formation energies of four low-indexed surfaces, including (001), (100), (110) and (011), of tin dioxide (SnO2) terminated by nonmetals (H, N, O, F, Cl, Br, and I) have been studied with the frameworks of density functional theory. A strong dependence of relative surface stabilities on surface atoms has been presented based on the calculations. Several instructions, in particular the selection of specific precursors and morphology controlling agents, have been further illustrated as a guideline for experimentalists.

Bond dissociation energies of organic molecules

In this Account we have compiled a list of reliable bond energies that are based on a set of critically evaluated experiments. A brief description of the three most important experimental techniques for measuring bond energies is provided. We demonstrate how these experimental data can be applied to yield the heats of formation of organic radicals and the bond enthalpies of more than 100 representative organic molecules.

Correlations and volatility spillovers across commodity and stock markets: Linking energies, food, and gold

This paper employs a VAR-GARCH model to investigate the return links and volatility transmission between the S&P 500 and commodity price indices for energy, food, gold and beverages over the turbulent period from 2000 to 2011. Understanding the price behavior of commodity prices and the volatility transmission mechanism between these markets and the stock exchanges are crucial for each participant, including governments, traders, portfolio managers, consumers, and producers. For return and volatility spillover, the results show significant transmission among the S&P 500 and commodity markets. The past shocks and volatility of the S&P 500 strongly influenced the oil and gold markets. This study finds that the highest conditional correlations are between the S&P 500 and gold index and the S&P 500 and WTI index. We also analyze the optimal weights and hedge ratios for commodities/S&P 500 portfolio holdings using the estimates for each index. Overall, our findings illustrate several important implications for portfolio hedgers for making optimal portfolio allocations, engaging in risk management and forecasting future volatility in equity and commodity markets. © 2013 Elsevier B.V.

Gibbs energies of formation of rare earth oxysulfides

The standard Gibbs energy change accompanying the conversion of rare earth oxides to oxysulfides by reaction of rare earth oxides with diatomic sulfur gas has been measured in the temperature range 870 to 1300 K using the solid state cell: Pt/Cu+Cu2S/R2O2S+R2O3‖(CaO)ZrO2‖Ni+NiO, Pt where R=La, Nd, Sm, Gd, Tb, and Dy. The partial pressure of diatomic sulfur over a mixture of rare earth oxide (R2O3) and oxysulfide (R2O2S) is fixed by the dissociation of Cu2S to Cu in a closed system. The buffer mixture of Cu+Cu2S is physically separated from the rare earth oxide and oxysulfide to avoid complications arising from interaction between them. The corresponding equilibrium oxygen partial pressure is measured with an oxide solid electrolyte cell. Gibbs energy change for the conversion of oxide to the corresponding oxysulfide increases monotonically with atomic number of the rare earth element. Second law enthalpy of formation also shows a similar trend. Based on this empirical trend Gibbs energies of formation of oxysulfides of Pr, Eu, Ho, and Er are estimated as a function of temperature.