Panel I: Connecting 2nd Law Analysis with Economics, Ecology and Energy Policy

The present paper is a review of several papers from the Proceedings of the Joint European Thermodynamics Conference, held in Brescia, Italy, 1–5 July 2013, namely papers introduced by their authors at Panel I of the conference. Panel I was devoted to applications of the Second Law of Thermodynamics to social issues—economics, ecology, sustainability, and energy policy. The concept called Available Energy which goes back to mid-nineteenth century work of Kelvin, Rankine, Maxwell and Gibbs, is relevant to all of the papers. Various names have been applied to the concept when interactions between the system of interest and an environment are involved. Today, the name exergy is generally accepted. The scope of the papers being reviewed is wide and they complement one another well

PRACTICAL APPROACHES FOR THE APPLICATION OF EXERGY COST THEORY TO ENERGY CONVERSION SYSTEMS

The Exergy Cost Theory (ECT) was proposed as a complete and formalized method to account for the exergy cost of system products, defining criteria for optimization and diagnosis purposes. In this paper, different practical approaches for the application of the Exergy Cost Analysis are presented and comparatively applied to the CGAM problem. An emphasis has been specially put on the possible approaches to define and to solve the system of exergy cost balances, including the definition of auxiliary relations and the reallocation of the exergy cost of residues. It is found that the definition of the functional diagram and the numerical solution of the system through Input-Output analysis seems to be preferable with respect to other approaches

The Exergy Cost Theory Revisited

This paper reviews the fundamentals of the Exergy Cost Theory, an energy cost accounting methodology to evaluate the physical costs of products of energy systems and their associated waste. Besides, a mathematical and computationally approach is presented, which will allow the practitioner to carry out studies on production systems regardless of their structural complexity. The exergy cost theory was proposed in 1986 by Valero et al. in their “General theory of exergy savings”. It has been recognized as a powerful tool in the analysis of energy systems and has been applied to the evaluation of energy saving alternatives, local optimisation, thermoeconomic diagnosis, or industrial symbiosis. The waste cost formation process is presented from a thermodynamic perspective rather than the economist’s approach. It is proposed to consider waste as external irreversibilities occurring in plant processes. A new concept, called irreversibility carrier, is introduced, which will allow the identification of the origin, transfer, partial recovery, and disposal of waste

Conceptualizing a credits trading approach towards corporate social responsibility credits

Life Cycles of both products and services significantly consume renewable and non-renewable resources across a worldwide scale. Thus, eliciting an enormous environmental impact, that is known to disproportionately instigate crises into the socio-economic and political domains of our civilization. Therefore, Creation of Shared Value and Corporate Social Responsibility (CSR) have been considered by Policy makers, Public and Private Institutions. In addition to Corporate Philanthropy, CSR practices also encompass a wide spectrum of activities, including Stakeholder safety/welfare, designing sustainable products and ecological restoration to name a few which are ascertained to capital and knowledge intensive in nature. Therefore, this paper primarily structures the scope of CSR and proposes a mechanism for trading Corporate Social Responsibility credits in order to incentivize stakeholder centered business practices. Furthermore, the CSR credits trading methodology would entail similar mechanisms used by its remotely successful predecessors namely, tax incentives, tradable credits/certificates and flexible mechanisms for implementing sustainable projects. The CSR credits trading methodology is envisioned to entail a more holistic approach towards overall Sustainability when compared to Carbon Offsets/Renewable Energy Certificates which are more focused towards reducing the environmental footprint.The author acknowledges the contribution of MIT Portugal Program, University of Minho and Fundação para a Ciência e Tecnologia (FCT), Portugal (Foundation Of Science and Technology, Portugal) for the scholarship grant SFRH / BD / 33794 / 2009

Exergy and Exergy Cost Analysis of production systems incorporating renewable energy sources

Exergy is a thermodynamic quantity capable of measuring the conversion of material and energy flows into comparable terms based on the capacity of such flows to generate mechanical work as a useful effect and identifying and quantifying the thermodynamic inefficiencies of a generic process by means of the exergy destruction term. Because of its properties, an exergy is a convenient tool for the calculation of the global resource consumption of both natural and engineering processes. Therefore, there are different exergy-based approaches. Every exergy-based approach has its advantages and its drawbacks. It even has its own spatial and temporal domain [1]. There are different exergy-based approaches that have been reviewed which are EMergy, Extended Exergy, Cumulative Exergy Consumption, Exergetic life cycle assessment, and Thermoeconomics. Reviewing different exergy approaches, especially the approaches that introduce the externalities like Labour, Capital, and environmental cost with their equivalent exergy values will help to develop an approach that avoids the drawbacks and take advantage of other approaches. Exergy-based account methodologies do not account for the ecological processes and products. This is something savior if sustainability is the aim and the goal. The indirect cost of resource consumption must be counted. The exergy cost of mineral resources which are not renewable is not their chemical exergy embodied in them only but also the cost of exergy that has been to be spent to reconcentrate these resources to be available for the upcoming generations [2]. As it is a matter of sustainability, considering the indirect exergy cost is very important. Each exergy-based methodology has its own spatial and temporal boundary. Some of them account only for the exergy consumed during the operation phase like the basic exergy analysis and some of them extend its spatial boundary to include the ecological cumulative exergy cost of a specific product [3]. The ecological cumulative exergy consumption ECEC approach has been introduced by Szarjut. Another approach extends its spatial boundary including the economy of the region or a country where the analysis takes place. This allows some other externalities like money and labor to be accounted in form of exergy. This approach is the extended exergy analysis EEA. This thesis presents a conceptual development of sustainability evaluation, through an exergy-based Indicator, by using the new concept of the Thermoeconomic Environment (TEE). The exergy-based accounting methods here considered as a background are the Extended Exergy Accounting (EEA), which can be used to quantify the exergy cost of externalities like labor, monetary inputs, and pollutants, and the Cumulative Exergy Consumption (CExC), which can be used to quantify the consumption of primary resources “embodied” in a final product or service. Also, the new concept of bioresource stock replacement cost is presented, highlighting how the framework of the TEE offers an option for evaluating the exergy cost of products of biological systems. The sustainability indicator is defined based on the exergy cost of all resources directly and indirectly consumed by the system, the equivalent exergy cost of all externalities implied in the production process and, the exergy cost of the final product.Exergy is a thermodynamic quantity capable of measuring the conversion of material and energy flows into comparable terms based on the capacity of such flows to generate mechanical work as a useful effect and identifying and quantifying the thermodynamic inefficiencies of a generic process by means of the exergy destruction term. Because of its properties, an exergy is a convenient tool for the calculation of the global resource consumption of both natural and engineering processes. Therefore, there are different exergy-based approaches. Every exergy-based approach has its advantages and its drawbacks. It even has its own spatial and temporal domain [1]. There are different exergy-based approaches that have been reviewed which are EMergy, Extended Exergy, Cumulative Exergy Consumption, Exergetic life cycle assessment, and Thermoeconomics. Reviewing different exergy approaches, especially the approaches that introduce the externalities like Labour, Capital, and environmental cost with their equivalent exergy values will help to develop an approach that avoids the drawbacks and take advantage of other approaches. Exergy-based account methodologies do not account for the ecological processes and products. This is something savior if sustainability is the aim and the goal. The indirect cost of resource consumption must be counted. The exergy cost of mineral resources which are not renewable is not their chemical exergy embodied in them only but also the cost of exergy that has been to be spent to reconcentrate these resources to be available for the upcoming generations [2]. As it is a matter of sustainability, considering the indirect exergy cost is very important. Each exergy-based methodology has its own spatial and temporal boundary. Some of them account only for the exergy consumed during the operation phase like the basic exergy analysis and some of them extend its spatial boundary to include the ecological cumulative exergy cost of a specific product [3]. The ecological cumulative exergy consumption ECEC approach has been introduced by Szarjut. Another approach extends its spatial boundary including the economy of the region or a country where the analysis takes place. This allows some other externalities like money and labor to be accounted for in form of exergy. This approach is the extended exergy analysis EEA. This thesis presents a conceptual development of sustainability evaluation, through an exergy-based Indicator, by using the new concept of the Thermoeconomic Environment (TEE). The exergy-based accounting methods here considered as a background are the Extended Exergy Accounting (EEA), which can be used to quantify the exergy cost of externalities like labor, monetary inputs, and pollutants, and the Cumulative Exergy Consumption (CExC), which can be used to quantify the consumption of primary resources “embodied” in a final product or service. Also, the new concept of bioresource stock replacement cost is presented, highlighting how the framework of the TEE offers an option for evaluating the exergy cost of products of biological systems. The sustainability indicator is defined based on the exergy cost of all resources directly and indirectly consumed by the system, the equivalent exergy cost of all externalities implied in the production process and, the exergy cost of the final product

THERMODYNAMICS OF DEVELOPMENT OF ENERGY SYSTEMS WITH APPLICATIONS TO THERMAL MACHINES AND LIVING ORGANISMS

We define and analyse thermodynamic limits for various traditional and work-assisted processes of sequential development with finite rates important in engineering and biology. The thermodynamic limits are expressed in terms of classical exergy change and a residual minimum of dissipated exergy, or some extension including time penalty. We consider processes with heat and mass transfer that occur in a finite time and with equipment of finite dimension. These processes include heat and separation operations and are found in heat and mass exchangers, thermal networks, energy converters, energy recovery units, storage systems, chemical reactors, and chemical plants. Our analysis is based on the condition that in order to make the results of thermodynamic analyses usable in engineering economics it is the thermodynamic limit, not the maximum of thermodynamic efficiency, which must be overcome for prescribed process requirements. A creative part of this paper outlines a general approach to the construction of `Carnot variables´ as suitable controls. Finite-rate, endoreversible models include minimal irreducible losses caused by thermal resistances to the classical exergy potential. Functions of extremum work, which incorporate residual minimum entropy production, are formulated in terms of initial and final states, total duration and (in discrete processes) number of stages

Sustainable car lifecycle design taking inspiration from natural systems and thermodynamics

This conference paper discusses new methods of organising industrial design process knowledge and more holistic approaches to implementing more efficient and sustainable ways of manufacturing, using and disposing of vehicles and products. The paper exposes the need for a creative developmental tool and method, which from a systems approach adopts the rules and logic of the physical biosphere in order to increase the designer’s potential for embracing sustainable product development. The use of trophic structures and the combination of knowledge from biology, economics, thermodynamics and business are implemented in the proposed new method of simulating sustainable product development from the project’s outset. This will provide guidelines that the car industry could use to achieve an ideal state for ecological, economical and social sustainability. The research focused on how to ensure a future with less resource scarcity and greenhouse effects which would otherwise imply more significant changes to the established economic, social and environmental systems. Research involved a wide review of related literature ranging from the exploitation of natural resources and current economic structures, to product development processes, to devise a tool that will guide the way for sustainable innovation in the automotive industry. As a result, an integral evaluation method incorporating ecological, economic and social measurements has been devised to inform manufacturers and allow them to design, produce and distribute vehicles, and put them into use with the lowest ecological impact. Through this paper, jointly written by Conti with Martinez (whose PhD was co-supervised by Conti) and English, £10K of Higher Education Innovation Fund (HEIF 2011–15) was raised through Northumbria University Research and Business Services. This allowed the development of a Web-based App to enable designers to be more socially responsible by creating early design concepts to be measured in terms of sustainability and life-cycle impact

Advanced methods for sustainable energy systems in operation and design of district heating networks

District heating networks (DHN) are an efficient way of providing thermal energy to consumers. Current state of the art shows that DHNs are developing towards smart thermal networks in integrated energy systems while their design is based upon the principles of sustainability. Based on that, this thesis covers two main research areas: Operation and design of district heating systems. In part A of this thesis, advanced methods for DHN operation are developed with the help of exergetic and thermoeconomic analysis. This includes the formulation of exergetic cost balances for graph-based network models. Intrinsic part is the deployment of an algebraic matrix, which determines the exergetic costs for dynamic system modeling. A case study of a real-existing network provides evidence that the proposed methodology offers new insights into individual allocation of costs which helps to assess the feasibility of third-party integration and the integration of distributed energy sources. In part B of this thesis, a new indicator called “load deviation index (LDI)” is proposed to link demand side measures (DSM) with the sustainable design of DHN systems. For that, a business-focused design framework s proposed which takes the critical influences of DHN into account while avoiding a too high detail. DSM behavior is analyzed from a system perspective and its impact on DHN design is studied in two case studies. While one focuses on benchmarks for different design options using a multi-criteria sustainability metric, another gives detailed insights into the usefulness of the proposed framework for design purposes through assessing the impact of DSM on possible design improvements using a multi-objective optimization approach

Application of Thermoeconomics to Assess and Improve the Efficiency of Bioenergy Production Plants and Land-To-Tank Cycles

La humanidad se encuentra en una doble encrucijada energética y climática. Ambos aspectos están íntimamente relacionados con el consumo de petróleo. Para solucionar el problema diferentes países están implementando políticas de reducción del consumo de combustibles fósiles, entre ellas la producción y consumo de energías renovables. El problema se ve acentuado en el sector del transporte, dependiente de los combustibles fósiles en mayor medida. El transporte depende del petróleo aproximadamente en un 98% en la Unión Europea y es el único sector económico cuyas previsiones estiman un continuo incremento en las emisiones de gas de efecto invernadero. La bioenergía es la fuente de energía renovable más utilizada en la actualidad y su relevancia en el futuro se prevé aún mayor. La bioenergía actualmente constituye más de dos tercios de la energía renovable de la Unión Europea y se espera que en 2020 acapare el 50% del consumo renovable y alrededor del 11% del consumo total de energía de los Estados miembros. Sin embargo, a diferencia de otras fuentes de energía, generar ahorros netos de gases de efecto invernadero con la bioenergía depende del proceso de producción. Procesos ineficientes pueden producir más gases de efecto invernadero que el combustible fósil que pretenden sustituir. La eficiencia en los procesos de producción, tanto a nivel de planta como en el ciclo de vida, necesita ser optimizada para reducir las emisiones al máximo. El biodiesel, sustituto natural del diesel fósil, es uno de los combustibles alternativos para el transporte más importantes, especialmente en Europa. No obstante, procesos ineficientes pueden conllevar el consumo de grandes cantidades de combustibles fósiles y emisiones elevadas de gases de efecto invernadero. Este puede ser el caso, especialmente, del biodiesel producido a partir de cultivos energéticos. Asegurar la sostenibilidad de los biocarburantes es un requisito obligatorio para los Estados miembros de la UE. La Directiva europea de energías renovables centra la sostenibilidad en la reducción de las emisiones de gases de efecto invernadero y en la protección de la biodiversidad y las tierras de alto stock en carbono. Una enmienda a la Directiva propuesta por la Comisión Europea plantea incrementar el nivel obligatorio de reducción de emisiones al 60% comparado con los combustibles fósiles. Si esta enmienda se aprueba, el biodiesel de ciertos cultivos energéticos podría verse excluido en la UE si los procesos de producción no mejoran, tal como refleja la evaluación de impacto realizada por la Comisión Europea. Por otra parte, el marco legislativo actual no tiene en cuenta el consumo de recursos no renovables. La presente tesis doctoral presenta una metodología basada en la termoeconomía para analizar posibles mejoras adicionales a introducir en los procesos de producción, para mantener el sector del biodiesel en Europa. El análisis input-output termoeconómico integra el segundo principio de la termodinámica con el análisis input-output económico, así como el análisis de flujos de materia y de ciclo de vida para proporcionar un procedimiento de evaluación riguroso enfocado en el ahorro energético, la sostenibilidad y la renovabilidad de procesos bioenergéticos. Mediante el uso de exergía como medida cuantitativa y cualitativa, este procedimiento constituye una herramienta útil para analizar en detalle los procesos de producción, identificar ineficiencias y proponer soluciones tales como la integración de procesos, la sustitución de materiales, la mejora de la eficiencia de componentes y la recirculación de flujos. Esta tesis doctoral aplica dicha metodología a una planta de transesterificacion de biodiesel y al ciclo de vida del biodiesel producido a partir de colza, girasol, palma, soja y aceites usados. En la tesis doctoral se definen tres conceptos: el ratio de renovabilidad, que mide la proporción de exergía renovable usada en el proceso con respecto al consumo de exergía total; la tasa de retorno exergético (Exergy return on investment, ExROI) que evalúa la cantidad de exergía contenida en el biodiesel por unidad de recursos no renovables consumidos, y el factor exergoecológico, que mide el ratio entre el coste exergético directo y el coste exergoecológico y permite evaluar la capacidad de mejora de los procesos directos en los ciclos de producción. Además, se presenta una metodología de análisis de sensibilidad para permitir comprender el efecto en los resultados de la introducción de cambios en el proceso. Esta tesis doctoral muestra que el ciclo de vida del biodiesel puede ser mejorado mediante la introducción de cambios en el proceso, de forma que se obtienen valores de ExROI de alrededor del 25 y ratios de renovabilidad de cerca del 98%, es decir, por cada unidad de exergía no renovable consumida en el proceso se obtienen 25 unidades de biodiesel y tan sólo un 2% de los costes exergéticos son de origen no renovable. Con esto, el biodiesel puede ser cinco veces más sostenible que el diésel fósil, desde el punto de vista del consumo de recursos no renovables. La tesis también demuestra que con la aplicación de dichas medidas, el biodiesel puede reducir las emisiones de gases de efecto invernadero más allá del límite del 60% propuesto en la enmienda de la Directiva y que puede incluso reducir las emisiones por encima del 100% comparado con el diésel fósil. Todo ello con beneficios socio-económicos y reducción de cambios directos en el uso de tierras. Aunque la metodología propuesta no sirve para evaluar otros impactos potenciales de la bioenergía, tales como los cambios indirectos en el uso de tierras, la disponibilidad de alimentos para consumo humano y el impacto en el uso de tierras arables, estos aspectos son también analizados, intentando aportar una visión ecuánime en estos temas tan controvertidos

Exergy and Thermoeconomic Analyses of Central Receiver Concentrated Solar Plants Using Air as Heat Transfer Fluid

The latest developments in solar technologies demonstrated that the solar central receiver configuration is the most promising application among concentrated solar power (CSP) plants. In CSPs solar-heated air can be used as the working fluid in a Brayton thermal cycle and as the heat transfer fluid for a Rankine thermal cycle as an alternative to more traditional working fluids thereby reducing maintenance operations and providing the power section with a higher degree of flexibility To supply thermal needs when the solar source is unavailable, an auxiliary burner is requested. This configuration is adopted in the Julich CSP (J-CSP) plant, operating in Germany and characterized by a nominal power of 1.5 MW, the heat transfer fluid (HTF) is air which is heated in the solar tower and used to produce steam for the bottoming Rankine cycle. In this paper, the J-CSP plant with thermal energy storage has been compared with a hybrid CSP plant (H-CSP) using air as the working fluid. Thermodynamic and economic performances of all the simulated plants have been evaluated by applying both exergy analysis and thermoeconomic analysis (TA) to determine the yearly average operation at nominal conditions. The exergy destructions and structure as well as the exergoeconomic costs of products have been derived for all the components of the plants. Based on the obtained results, the thermoeconomic design evaluation and optimization of the plants has been performed, allowing for improvement of the thermodynamic and economic efficiency of the systems as well as decreasing the exergy and exergoeconomic cost of their products