+ Site Statistics
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on LinkedInFollow on LinkedIn

+ Translate

Exergy and extended exergy accounting of very large complex systems with an application to the province of Siena, Italy

Exergy and extended exergy accounting of very large complex systems with an application to the province of Siena, Italy

Journal of Environmental Management 86(2): 372-382

This paper describes the application of exergy and extended exergy analyses to large complex systems. The system to be analysed is assumed to be at steady state, and the input and output fluxes of matter and energy are expressed in units of exergy. Human societies of any reasonable extent are indeed Very Large Complex Systems and can be represented as interconnected networks of N elementary "components", their Subsystems; the detail of the disaggregation depends on the type and quality of the available data. The structural connectivity of the "model" of the System must correctly describe the interactions of each mass or energy flow with each sector of the society: since it is seldom the case that all of these fluxes are available in detail, some preliminary mass- and energy balances must be completed and constitute in fact a part of the initial assumptions. Exergy accounting converts the total amount of resources inflow into their equivalent exergetic form with the help of a table of "raw exergy data" available in the literature. The quantification of each flow on a homogeneous exergetic basis paves the way to the evaluation of the efficiency of each energy and mass transfer between the N sectors and makes it possible to quantify the irreversible losses and identify their sources. The advantage of the EEA, compared to a classical exergy accounting, is the inclusion in the system balance of the exergetic equivalents of three additional "Production Factors": human Labour, Capital and Environmental Remediation costs. EEA has an additional advantage: it allows for the calculation of the efficiency of the domestic sector (impossible to evaluate with any other energy- or exergy-based method) by considering the working hours as its product. As implied in the title, an application of the method was made to a model of the province of Siena (on a year 2000 database): the results show that the sectors of this Province have values of efficiency close to the Italian average, with the exception of the commercial and energy conversion sectors that are more efficient, in agreement with the rather peculiar socio-economic situation of the Province. The largest inefficiency is found to be in the transportation sector, which has an efficiency lower then 30% in EEA and lower than 10% in classical exergy accounting.

(PDF emailed within 0-6 h: $19.90)

Accession: 021008331

Download citation: RISBibTeXText

PMID: 17064841

DOI: 10.1016/j.jenvman.2006.04.016

Related references

Advances in exergy analysis: a novel assessment of the Extended Exergy Accounting method. Applied Energy 113: 1405-1420, 2014

Spatial differences of exergy use of cement manufacturing industry in China based on extended exergy accounting method. Journal of Geographical Sciences 25(11): 1393-1407, 2015

Performance of the Dutch Energy Sector based on energy, exergy and Extended Exergy Accounting. Energy 31(15): 3135-3144, 2006

An application of the extended exergy accounting method to the Turkish society, year 2006. Energy 40(1): 151-163, 2012

Energy, exergy, and extended-exergy analysis of the Norwegian society 2000. Energy 30(5): 649-675, 2005

Exergy, exergy ratio, and specific exergy as measures of ecosystem health of the Nakdong River. Korean Journal of Limnology. December; 324: 281-287 Serial Number 88, 1999

Ecological accounting for China based on extended exergy. Renewable and Sustainable Energy Reviews 37: 334-347, 2014

Extended exergy accounting applied to biodiesel production. Energy 35(7): 2861-2869, 2010

Application of exergy and specific exergy as ecological indicators of coastal areas. Aquatic Ecosystem Health and Management, 33: 419-430, 2000

A more general exergy function and its application to the definition of exergy efficiency. Energy 87: 352-360, 2015

Ecological accounting based on extended exergy: a sustainability perspective. Environmental Science & Technology 48(16): 9826-9833, 2015

Extended exergy based ecological accounting for the transportation sector in China. Renewable and Sustainable Energy Reviews 32: 229-237, 2014

A revised calculation of the econometric factors α- and β for the Extended Exergy Accounting method. Ecological Modelling 222(4): 1060-1066, 2011

Extended exergy-based sustainability accounting of a household biogas project in rural China. Energy Policy 68: 264-272, 2014

Extended exergy accounting applied to energy recovery from waste: The concept of total recycling. Energy 28(13): 1315-1334, 2003