20 th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems Padova, Italy, June 2007 ECOS2007 Guidelines to develop software for thermoeconomic analysis of energy systems César Torres, Antonio Valero and Erika Perez Centro de Investigación de Recursos y Consumos Energéticos University of Zaragoza (SPAIN)

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis2 Objectives The main objective of this paper is to show the guidelines to develop a software for the thermoeconomic analysis of energy systems, making special emphasis on:  The thermoeconomic data model  The cost formation process of products and residues  The application to thermoeconomic diagnosis

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis3 Thermoeconomic Model Economic Model plant: ProductiveStructure … getDeviceCost(device) : float getResourceCost(flow): float …. Productive Structure plant: String flows: Collection devices: Collection … Flow Id: Number fromDevice: Device toDevice: Device type: TypeOfFlow … Device Id: Number name: String type: TypeOfDevice Fuel: Collection Product:Collection … 1..m 1..n Thermodynamic Model getExergy(flow) : float …. plant: ProductiveStructure …

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis4 Productive and Dissipative Components  An energy system has two types of components:  Productive components  Dissipative components  Productive components provide:  Functional Products  Resources (Fuel) to other process  Residues and waste disposals  Dissipative components are required to:  Reduce or eliminate the environment impact of residues and wastes  Maintain the operation conditions of the system, from a physical and/or a legal point of view  Improve the efficiency of the system

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis5 Productive Structure NrDeviceFuelProductType 1CombustorE5E5 E 2 –E 1 P 2CompressorE6E6 E 1 –E 0 P 3TurbineE 2 –E 3 E 6 +E 7 P 4HRSGE 3 –E 4 E8E8 P 5StackE4E4 E9E9 D

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis6 The Fuel-Product Table  The productive diagram is a graphic representation of the thermoeconomic model of the plant.  The inputs of a component are its resources  The outputs of a component are its products  The Fuel Product table is the adjacency matrix of the productive graph F0F0 F1F1 …FjFj …FnFn P0P0 E 01 …E 0j …E 0n P1P1 E 10 E 11 …E 1j …E 1n ………………… PiPi E i0 E i1 …E ij …E in ………………… PnPn E n0 E n1 …E nj …E nn Represents the production of the i-th component becomes fuel of the j-th component Represents the external resources Represents the system outputs

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis7 The Fuel Product Table (II)  The productive graph and its Fuel Product table can be applied to:  Thermoeconomic Optimization (TFA)  Thermoeconomic Diagnosis  Identify the cost formation process of product and residues  Analyze different aggregation level of a system  The FP table can be built automatically from the information provided by the productive structure of the system. Valero and Torres proposed in 1988 an algorithm based on the Exergy Cost Theory.

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis8 FP Table Builder Productive Structure Build Incidence Matrices Build Incidence Matrices Flow Exergy Values Compute FP Table

June 26, 2007Guidelines to develop software for thermoeconomic analysis9 TAESS Intro Pannel

June 26, 2007Guidelines to develop software for thermoeconomic analysis10 TAESS Data Input

June 26, 2007Guidelines to develop software for thermoeconomic analysis11 TAESS General data 1

June 26, 2007Guidelines to develop software for thermoeconomic analysis12 TAESS FP Table

June 26, 2007Guidelines to develop software for thermoeconomic analysis13 TAESS FP Diagram

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis14 Objectives The main objective of this paper is to show the guidelines to develop a software for the thermoeconomic analysis of energy systems, making special emphasis on:  The thermoeconomic data model  The cost formation process of products and residues  The application to thermoeconomic diagnosis

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis15 The Cost Model The exergy costing rules can be written as:  The cost of product is equal to the cost of the resources required to obtain it, plus the cost of the residues generated:  The cost of each flow making up the product is proportional to its exergy: [exergy cost (kW)] [exergoeconomic cost (€/h)]  The cost of the external resources is known:

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis16 Residue Cost Distribution  The cost of a residue must be allocated to one or several productive components:  To determine the values of C ri we must define the distribution cost ratios (RCD) as:  Therefore, the cost of the residues allocated to each productive unit, is given by: The Residue Cost Distribution ratios represent the portion of the cost of the residue dissipated in the r-th component which has been generated in the i-th productive component. i j r s r i

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis17 Costing Equations  The unit production cost could be obtained by solving the following system of lineal equations: is a (n x n) matrix whose elements are the unit consumption values, defined as: is a (n x n) matrix whose elements are the ratios of the residues generated per production unit: is a (n x 1) vector whose elements are the cost of the external resources consumed in each component per production unit:

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis18 Cost Decomposition  The unit exergy cost of the product could be decomposed into two parts: represents the unit production cost due to irreversibilities of the components: represents the unit production cost due to the residues:

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis19 Cost Decomposition Activity Diagram FP Table Build Residue Cost Distribution Ratios Compute Build Compute

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis20 Themoeconomic Analysis Sequence Diagram FPR model Thermoeconomic Analysis FP BuilderProductive StructureThermodynamic ModelEconomic Model buildFP(state) getStructure() getExergies(state) getResourcesCost() FP table productive structure exergies resource cost

June 26, 2007Guidelines to develop software for thermoeconomic analysis21 TAESS Matrix RP

June 26, 2007Guidelines to develop software for thermoeconomic analysis22 TAESS Cost Analysis Report

June 26, 2007Guidelines to develop software for thermoeconomic analysis23 TAESS Cost Formation Graph

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis24 Objectives The main objective of this paper is to show the guidelines to develop a software for the thermoeconomic analysis of energy systems, making special emphasis on:  The thermoeconomic data model  The cost formation process of products and residues  The application to thermoeconomic diagnosis

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis25 Thermoeconomic Diagnosis  It is based on the comparison of two thermodynamic states  Obtains a set of common indexes for every component of the system, whose could be used in combination with other parameters to provide useful information for the plant operation.  Relates the variation of the irreversibilities and resources consumption to the variation of the efficiency of each component. The objective of the thermoeconomic diagnosis is the location and quantification of the anomalies causing the reduction of the system efficiency.

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis26 Malfunction and Dysfunction  The irreversibility increase of a component could be decomposed into two contributions:  The irreversibility increase due to a variation of the efficiency of the component itself (MALFUNCTION).  The variation of the production objective of the component due to the malfunctions of others components (DYSFUNCTION)  The sum of the malfunctions caused by a component is called MALFUNCTION COST: DF ji represents the irreversibility increase of the component j-th caused by a malfunction in the i-th component DF k0 represents the irreversibility increase of the component k-th caused by a variation of the outputs (final products or residues)

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis27 The Fuel Impact Formula There are two approaches to allocate the fuel impact of a system  The cost of the internal malfunctions are valuated by the production cost and they include the residues variation effect.  The costs of the internal malfunctions are valuated by the production cost due only to irreversibilities. The cost of the residues variation is considered as another contribution to the fuel impact.

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis28 Compute Thermoeconomic Diagnosis Activity Diagram FPR Model for Reference State Build Compute FPR Model for Current State Compute

June 26, 2007Guidelines to develop software for thermoeconomic analysis29 TAESS Diagnosis

June 26, 2007Guidelines to develop software for thermoeconomic analysis30 TAESS Diagnosis Report

June 26, 2007Guidelines to develop software for thermoeconomic analysis31 TAESS Irreversibility Analysis Graph

June 26, 2007Guidelines to develop software for thermoeconomic analysis32 TAESS Fuel Impact Analysis Graph

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis33 Productive and Dissipative Structures  It has been shown there is not only a productive structure but a dissipative structure  The dissipative structure describes how the process of residues and wastes formation is. It could be as complex as the productive one.  The productive and dissipative structures are not independent but they are interrelated. A malfunction in a component cause both an increase of the irreversibilities of the components and an increase of the residues.  Therefore, to make a correct thermoeconomic diagnosis we must define both good productive and dissipative structures.

ECOS2007 June 26, 2007Guidelines to develop software for thermoeconomic analysis34  This paper should be understood as a functional description for developing software for thermoeconomic analysis of energy systems.  It includes the following new contributions:  A FP table builder algorithm.  A cost decomposition methodology.  Fuel Impact analysis of residues and wastes  From now on the problem of thermoeconomic diagnosis should not be to compute cost indexes but analyzing the results.  A demo program, called TAESS, is available from the authors at to illustrate the ideas presented in the paper. Conclusions

June 26, 2007Guidelines to develop software for thermoeconomic analysis35 Exergoeconomics web page

20 th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems Padova, Italy, June 2007 ECOS2007 Thank you very much for your attention