Going beyond energy intensity to understand the energy metabolism of nations: the case of Argentina

The link between energy consumption and economic growth has been widely studied in the economic literature. Understanding this relationship is important from both an environmental and a socio-economic point of view, as energy consumption is crucial to economic activity and human environmental impact. This relevance is even higher for developing countries, since energy consumption per unit of output varies through the phases of development, increasing from an agricultural stage to an industrial one and then decreasing for certain service based economies. In the Argentinean case, the relevance of energy consumption to economic development seems to be particularly important. While energy intensity seems to exhibit a U-Shaped curve from 1990 to 2003 decreasing slightly after that year, total energy consumption increases along the period of analysis. Why does this happen? How can we relate this result with the sustainability debate? All these questions are very important due to Argentinean hydrocarbons dependence and due to the recent reduction in oil and natural gas reserves, which can lead to a lack of security of supply. In this paper we study Argentinean energy consumption pattern for the period 1990-2007, to discuss current and future energy and economic sustainability. To this purpose, we developed a conventional analysis, studying energy intensity, and a non conventional analysis, using the Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) accounting methodology. Both methodologies show that the development process followed by Argentina has not been good enough to assure sustainability in the long term. Instead of improving energy use, energy intensity has increased. The current composition of its energy mix, and the recent economic crisis in Argentina, as well as its development path, are some of the possible explanations.

Cap a l'autosuficiència energètica: barri La Plana, Sitges

En el present estudi s’ha analitzat si és possible l’autosuficiència energètica al barri projectat de La Plana de Sitges a partir de fonts renovables d’energia. S’ha realitzat un anàlisi de l’oferta potencial del barri de La Plana, format per habitatges unifamiliars i plurifamiliars, serveis i equipaments i s’ha comparat el potencial de producció energètica dels recursos renovables locals a cada subsistema i pel sistema de La Plana. Diferenciant si són una Oferta estàndard (4.000 MWh/a) seguint la Normativa d’ecoeficiència de Sitges o bé una Oferta renovable (19.000 MWh/a) segons un Ecobarri proposat en aquest projecte a partir d’energia solar fotovoltaica i tèrmica. En l’estudi de la demanda, diferenciant entre una Demanda estàndard (39.000 MWh/a), respon al total de La Plana seguint el consum d’un habitatge tipus de la mitjana catalana (ICAEN, 2002) i una Demanda eficient (20.800 MWh/a) seguint un model de baix consum projectat en un Ecobarri de Barcelona. (Vallbona, 2009). Per analitzar de forma detallada les variables d’oferta i demanda, s’han proposat quatre escenaris diferents on es valoren l’autosuficiència energètica del sistema de la Plana i aspectes ambientals d’emissions derivades de la utilització de l’energia. El primer escenari és l’estàndard i és el resultat d’analitzar conjuntament una oferta i una demanda estàndard. Al segon escenari conflueixen una Oferta Estàndard i una Demanda Eficient. En el tercer escenari coincideixen una Oferta Renovable i una Demanda Estàndard. El quart i últim escenari respon a la proposta d’Ecobarri on l’Oferta és renovable i la Demanda eficient. Tanmateix, s’ha realitzat un estudi sobre els aspectes econòmics de La Plana que s’estimen en uns beneficis per la venda de l’energia d’uns 5 milions d’euros anuals i uns costos d’instal·lació de 80 milions d’euros. Finalment s’ha constatat que és possible assolir una autosuficiència del 90% a l’escenari Ecobarri (oferta renovable - demanda eficient). Mitjançant la instal·lació de sistemes de captació solar a les cobertes, cobrint el 100% de la demanda d’ACS, i captadors solars FV, ambdues estratègies són viables i representen beneficis econòmics i una reducció d’emissions de l’ordre de 13.700 Tn CO2 equivalents anuals que suposen un estalvi del 88% respecte un escenari d’oferta i demanda estàndard.

Estudi energètic de les llars del barri de Haër (Senegal)

En el present estudi s’han analitzat quines són les fonts energètiques utilitzades a les llars de Haër, així com les repercussions que aquestes tenen sobre el medi natural i socioeconòmic de les famílies. Per tal de poder identificar quines són aquestes fonts i els seus efectes, s’ha realitzat un inventari i una diagnosi energètica. S’ha estudiat l’ús de l’energia en dos àmbits domèstics principals: la il·luminació i el cuinat, analitzant la freqüència d’ús i quantificant el consum energètic familiar. Les fonts energètiques detectades són: llenya, carbó, gas, querosè, piles i espelmes, de les quals, la llenya, el querosè i el carbó són les majoritàriament utilitzades. El consum energètic per càpita és de 2.100 kWh/any. Per altra banda, l’obtenció d’algunes d’aquestes fonts energètiques, suposen un cost econòmic molt elevat per les economies familiars, arribant a suposar un 60% dels ingressos. A partir de les dades obtingudes a la diagnosi, s’ha aplicat un indicador per tal de quantificar la magnitud de l’impacte sobre el medi produït pel model energètic seguit dins de les llars. L’indicador estudiat ha estat la petjada energètica, amb la qual s’ha traduït aquest consum en unitats de superfície biològicament productiva, requerida per absorbir el CO2 emès. El resultat ha estat que una persona produeix anualment 2,09·10-2 tCO2, que requereix de 7,53·10-3 gha/persona de superfície forestal per ser absorbides. S’ha comparat aquest resultat amb la petjada energètica domèstica calculada pel poble d’Araós, el qual, amb un model energètic totalment diferent, té una petjada energètica de 1,53 gha/persona. Un cop detectats els problemes o impactes causats pel model energètic actual, es proposa una alternativa energètica per tal de reemplaçar algunes fonts convencionals, principalment el querosè dels quinqués. Així doncs, mitjançant l’aprofitament de l’energia solar, es plantegen dos models fotovoltaics adaptats a dues tipologies de llars diferents, amb l’objectiu de minimitzar el cost i optimitzar els recursos energètics. Finalment es planteja una solució financera per abordar el cost inicial de la instal·lació solar.

Different trajectories of exosomatic energy metabolism for Brazil, Chile and Venezuela: using the MSIASM approach

Economic development goes hand in hand with an increase in the consumption of natural resources. Some analysts use material flows to describe such relationship [Eurostat 2001, Weisz et al., 2006], or exergy [Ayres et al., 2003]. Instead this paper will use a characterisation of the exosomatic energy metabolism based on expected benchmark values to describe possible constraints to economic development posed by available human time and energy. The aim of the paper is to identify types of exosomatic energy metabolism of different societies to interpret its consequences for economic development. This is done with the application of the accounting methodology called Multi-Scale Integrated Analysis of Societal Metabolism (MSIASM) to the particular case of energy metabolism for the analysis of the economies of Brazil, Chile and Venezuela.

Interlinkages and forecasting made possible by the use of the DECOIN analytical tool kit

This technical report is a document prepared as a deliverable [D4.3 Report of the Interlinkages and forecasting prototype tool] of a EU project – DECOIN Project No. 044428 - FP6-2005-SSP-5A. The text is divided into 4 sections: (1) this short introductory section explains the purpose of the report; (2) the second section provides a general discussion of a systemic problem found in existing quantitative analysis of sustainability. It addresses the epistemological implications of complexity, which entails the need of dealing with the existence of Multiple-Scales and non-equivalent narratives (multiple dimensions/attributes) to be used to define sustainability issues. There is an unavoidable tension between a “steady-state view” (= the perception of what is going on now – reflecting a PAST --& PRESENT view of the reality) versus an “evolutionary view” (= the unknown transformation that we have to expect in the process of becoming of the observed reality and in the observer – reflecting a PRESENT --& FUTURE view of the reality). The section ends by listing the implications of these points on the choice of integrated packages of sustainability indicators; (3) the third section illustrates the potentiality of the DECOIN toolkit for the study of sustainability trade-offs and linkages across indicators using quantitative examples taken from cases study of another EU project (SMILE). In particular, this section starts by addressing the existence of internal constraints to sustainability (economic versus social aspects). The narrative chosen for this discussion focuses on the dark side of ageing and immigration on the economic viability of social systems. Then the section continues by exploring external constraints to sustainability (economic development vs the environment). The narrative chosen for this discussion focuses on the dark side of current strategy of economic development based on externalization and the “bubbles-disease”; (4) the last section presents a critical appraisal of the quality of energy data found in energy statistics. It starts with a discussion of the general goal of statistical accounting. Then it introduces the concept of multipurpose grammars. The second part uses the experience made in the activities of the DECOIN project to answer the question: how useful are EUROSTAT energy statistics? The answer starts with an analysis of basic epistemological problems associated with accounting of energy. This discussion leads to the acknowledgment of an important epistemological problem: the unavoidable bifurcations in the mechanism of accounting needed to generate energy statistics. By using numerical example the text deals with the following issues: (i) the pitfalls of the actual system of accounting in energy statistics; (ii) a critical appraisal of the actual system of accounting in BP statistics; (iii) a critical appraisal of the actual system of accounting in Eurostat statistics. The section ends by proposing an innovative method to represent energy statistics which can result more useful for those willing develop sustainability indicators.

A first attempt of geographically-distributed Multi-scale integrated analysis of societal and ecosystem metabolism (MuSIASEM): mapping human time and energy throughput in metropolitan Barcelona

This study presents a first attempt to extend the “Multi-scale integrated analysis of societal and ecosystem metabolism (MuSIASEM)” approach to a spatial dimension using GIS techniques in the Metropolitan area of Barcelona. We use a combination of census and commercial databases along with a detailed land cover map to create a layer of Common Geographic Units that we populate with the local values of human time spent in different activities according to MuSIASEM hierarchical typology. In this way, we mapped the hours of available human time, in regards to the working hours spent in different locations, putting in evidence the gradients in spatial density between the residential location of workers (generating the work supply) and the places where the working hours are actually taking place. We found a strong three-modal pattern of clumps of areas with different combinations of values of time spent on household activities and on paid work. We also measured and mapped spatial segregation between these two activities and put forward the conjecture that this segregation increases with higher energy throughput, as the size of the functional units must be able to cope with the flow of exosomatic energy. Finally, we discuss the effectiveness of the approach by comparing our geographic representation of exosomatic throughput to the one issued from conventional methods.

Assessing the quality of alternative energy sources: Energy Return On the Investment (EROI), the metabolic pattern of societies and energy statistics

This paper presents an initial challenge to tackle the every so "tricky" points encountered when dealing with energy accounting, and thereafter illustrates how such a system of accounting can be used when assessing for the metabolic changes in societies. The paper is divided in four main sections. The first three, present a general discussion on the main issues encountered when conducting energy analyses. The last section, subsequently, combines this heuristic approach to the actual formalization of it, in quantitative terms, for the analysis of possible energy scenarios. Section one covers the broader issue of how to account for the relevant categories used when accounting for Joules of energy; emphasizing on the clear distinction between Primary Energy Sources (PES) (which are the physical exploited entities that are used to derive useable energy forms (energy carriers)) and Energy Carriers (EC) (the actual useful energy that is transmitted for the appropriate end uses within a society). Section two sheds light on the concept of Energy Return on Investment (EROI). Here, it is emphasized that, there must already be a certain amount of energy carriers available to be able to extract/exploit Primary Energy Sources to thereafter generate a net supply of energy carriers. It is pointed out that this current trend of intense energy supply has only been possible to the great use and dependence on fossil energy. Section three follows up on the discussion of EROI, indicating that a single numeric indicator such as an output/input ratio is not sufficient in assessing for the performance of energetic systems. Rather an integrated approach that incorporates (i) how big the net supply of Joules of EC can be, given an amount of extracted PES (the external constraints); (ii) how much EC needs to be invested to extract an amount of PES; and (iii) the power level that it takes for both processes to succeed, is underlined. Section four, ultimately, puts the theoretical concepts at play, assessing for how the metabolic performances of societies can be accounted for within this analytical framework.

Inequality across countries in energy intensities: an analysis of the role of energy transformation and final energy consumption

This paper analyzes the role of the energy transformation index and of final energy consumption per GDP unit in the disparities in energy intensity across countries. In that vein, we use a Theil decomposition approach to analyze global primary energy intensity inequality as well as inequality across different regions of the world and inequality within these regions. The paper first demonstrates the pre-eminence of divergence in final energy consumption per GDP unit in explaining global primary energy intensity inequality and its evolution during the 1971-2006 period. Secondly, it shows the lower (albeit non negligible) impact of the transformation index in global primary energy inequality. Thirdly, the relevance of regions as unit of analysis in studying crosscountry energy intensity inequality and their explanatory factors is highlighted. And finally, how regions around the world differ as to the relevance of the energy transformation index in explaining primary energy intensity inequality.

Energy dispersive X-Ray fluorescence : measuring elements in solid and liquid matrices

The subject of this project is about “Energy Dispersive X-Ray Fluorescence ” (EDXRF).This technique can be used for a tremendous variety of elemental analysis applications.It provides one of the simplest, most accurate and most economic analytical methods for thedetermination of the chemical composition of many types of materials.The purposes of this project are:- To give some basic information about Energy Dispersive X-ray Fluorescence.- To perform qualitative and quantitative analysis of different samples (water-dissolutions,powders, oils,..) in order to define the sensitivity and detection limits of the equipment.- To make a comprehensive and easy-to-use manual of the ‘ARL QUANT’X EnergyDispersive X-Ray Fluorescence’ apparatus

Characterization and simulation of a CdTe detector for use in PET

The Voxel Imaging PET (VIP) Path nder project got the 4 year European Research Council FP7 grant in 2010 to prove the feasibility of using CdTe detectors in a novel conceptual design of PET scanner. The work presented in this thesis is a part of the VIP project and consists of, on the one hand, the characterization of a CdTe detector in terms of energy resolution and coincidence time resolution and, on the other hand, the simulation of the setup with the single detector in order to extend the results to the full PET scanner. An energy resolution of 0.98% at 511 keV with a bias voltage of 1000 V/mm has been measured at low temperature T=-8 ºC. The coincidence time distribution of two twin detectors has been found to be as low as 6 ns FWHM for events with energies above 500 keV under the same temperature and bias conditions. The measured energy and time resolution values are compatible with similar ndings available in the literature and prove the excellent potential of CdTe for PET applications. This results have been presented in form of a poster contribution at the IEEE NSS/MIC & RTSD 2011 conference in October 2011 in Valencia and at the iWoRID 2012 conference in July 2012 in Coimbra, Portugal. They have been also submitted for publication to "Journal of Instrumentation (JINST)" in September 2012.

C-H···O H-bonded complexes: how does basis set superposition error change their potential-energy surfaces?

Geometries, vibrational frequencies, and interaction energies of the CNH⋯O3 and HCCH⋯O3 complexes are calculated in a counterpoise-corrected (CP-corrected) potential-energy surface (PES) that corrects for the basis set superposition error (BSSE). Ab initio calculations are performed at the Hartree-Fock (HF) and second-order Møller-Plesset (MP2) levels, using the 6-31G(d,p) and D95++(d,p) basis sets. Interaction energies are presented including corrections for zero-point vibrational energy (ZPVE) and thermal correction to enthalpy at 298 K. The CP-corrected and conventional PES are compared; the unconnected PES obtained using the larger basis set including diffuse functions exhibits a double well shape, whereas use of the 6-31G(d,p) basis set leads to a flat single-well profile. The CP-corrected PES has always a multiple-well shape. In particular, it is shown that the CP-corrected PES using the smaller basis set is qualitatively analogous to that obtained with the larger basis sets, so the CP method becomes useful to correctly describe large systems, where the use of small basis sets may be necessary

Development of a microprocessor controlled energy harvester using a Peltier element

Nowadays it is necessary to research other types of energy alternatives and find the way to supply and save the energy we waste. The aim of the project consist of programming a microprocessor to measure if an oven radiates heat to the exterior, for the measure It is used a Peltier element that generates a voltage depending of the temperature difference between the oven and the air of the place where the oven is situated; The energy generated by the oven will be recollected in a condensor. A sensor will be used to know the exact measure. The second part of the project the main propose, is the development of a harvester. The microprocessor will use the voltage produced by the Peltier element to supply the electricity that it needs to work. A low power circuit and the appropriate software are needed to save the voltage generated.

Precision determination of r(0)Lambda((MS)over-bar) from the QCD static energy

We use the recently obtained theoretical expression for the complete QCD static energy at next-to-next-to-next-to leading-logarithmic accuracy to determine r(0)Lambda((MS) over bar) by comparison with available lattice data, where r(0) is the lattice scale and Lambda((MS) over bar) is the QCD scale. We obtain r(0)Lambda((MS) over bar) = 0.622(-0.015)(+0.019) for the zero-flavor case. The procedure we describe can be directly used to obtain r(0)Lambda((MS) over bar) in the unquenched case, when unquenched lattice data for the static energy at short distances becomes available. Using the value of the strong coupling alpha(s) as an input, the unquenched result would provide a determination of the lattice scale r(0).

The Gibbs free energy of formation of a glass alloy

A simple expression for the Gibbs free energy of formation of a pure component or a eutectic alloy glass, relative to the stable crystalline phase (or phases) at the same temperature is deduced by use of thermodynamic arguments. The expression obtained is supposed to apply to both monocomponent and multicomponent liquid alloys that might become glasses from the supercooled liquid state, irrespective of the critical cooling rate needed to avoid crystallization.

Hindleg muscle energy and substrate balances in cold-exposed rats

Rats chronically cannulated in the carotid artery and the muscular branch of the femoral vein were subjected to a cold (4 °C) environment for up to 2 h. The changes in blood flow (measured with 46Sc microspheres) and arterio-venous differences in the concentrations of glucose, lactate, triacylglycerols and amino acids allowed the estimation of substrate (and energy) balances across the hindleg. Mean glucose uptake was 0.28mmol min21, mean lactate release was 0.33mmol min21 and the free fatty acid basal release of 0.31mmol min21 was practically zero upon exposure to the cold; the initial uptake of triacylglycerols gave place to a massive release following exposure. The measurement of PO·, PCO· and pH also allowed the estimation of oxygen, CO2 and bicarbonate balances and respiratory quotient changes across the hindleg. The contribution of amino acids to the energy balance of the hindleg was assumed to be low. These data were used to determine the sources of energy used to maintain muscle shivering with time. Three distinct phases were observed in hindleg substrate utilization. (1) The onset of shivering, with the use of glucose/glycogen and an increase in lactate efflux. Lipid oxidation was practically zero (respiratory quotient near 1), but the uptake of triacylglycerols from the blood remained unchanged. (2) A substrate-energy shift, with drastically decreased use of glucose/glycogen, and of lactate efflux; utilization of triacylglycerol as practically the sole source of energy (respiratory quotient approximately 0.7); decreasing uptake of triacylglycerol and increased tissue lipid mobilization. (3) The onset of a new heat-homeostasis setting for prolonged cold-exposure, with maintenance of muscle energy and heat production based on triacylglycerol utilization and efflux from the hindleg (muscle plus skin and subcutaneous adipose masses) contributing energy to help sustain heat production by the core organs and surrounding brown adipose tissue.