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V. CONCLUSIONS AND RECOMMENDATIONS

This study has presented an analysis of the potential relevance of the use of analytical tools based on the Second Law of thermodynamics to existing Federal energy conservation programs. It is believed to have addressed the most significant of potential applications and programs. However, this is a rapidly developing field with new applications continually arising that could change in detail the assessment provided herein. Despite this, it is not expected that foreseeable developments will alter substantially the major conclusions of this

effort.

The principal conclusions of this study are the following:

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practice. Both First Law and Second Law analysis techniques are used.

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Second Law availability analysis is a useful tool, but only one of a

number of directly pertinent planning and analysis tools.

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Second Law analyses provide useful information and insights about

energy systems, 1.e., where various energy losses of different types may occur, but do not determine what to do about such losses. The latter requires insight and invention.

In engineering analysis, the relative importance of Second Law analysis varies considerably between applications.

Application

Planning:

Second Law analysis is highly pertinent to planning and research priority setting and is already being used widely in this context,

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and assessment of new ideas.

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Design:

Energy analysis is only one of a number of performance measures that can be used in designing or evaluating energy conservation programs.

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Second Law analysis can be useful in the detailed design of a system. The more complex a system, the greater chance that it will be useful.

Monitoring:

In most cases, both First and Second Law analyses are not sufficient to establish practical efficiency goals. Other technical factors such as strength of materials, speeds of chemical reaction, needed rates of

production, corrosion and pollution control must be considered.

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There is little or no advantage to using Second Law analyses as opposed to energy accounting in monitoring the performance of an existing plant or system.

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In most cases examined, including those involving intra-industry comparisons, existing monitoring and reporting measures appear adequate. Exceptions involve complex processes with multiple energy streams. Second Law analysis does not resolve difficulties in making inter-industry comparisons; for example, comparing the efficiency

of aluminum with steel-making processes.

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In cases where different energy streams (i.e. steam and electricity)

are being sold to the public, an availability based pricing structure should be considered for customer equity purposes.

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Needs:

The potential applicability of Second Law analysis to the long-term policy realm of optimal resource allocation remains to be established. Research on this point is desirable.

upon development of better data, models, and further generalized

education and training.

-Appropriate intercomparisons require data for common reference states to be developed and defined.

-Fundamental research and applications are needed to further develop Second Law-based analytical tools and computer models. There will be some need to expand the data base of thermodynamic properties of materials widely used in commerce and industry.

-Specialized reference and course materials are required for education and training in many engineering disciplines particularly on

(a) fundamentals of thermodynamics

(b) calculation of thermodynamic properties applicable to conditions

found in industrial processes

(c) estimation of thermodynamic properties, and

(d) application of availability analysis.

In the final analysis, Second Law analysis techniques must be viewed in the context of a broader range of engineering tools and along with economic, institutional, political, and social factors in making important decisions in the energy conservation arena. The above conclusions establish no basis

for requiring Second Law efficiency analysis as a mandatory factor in controlling any particular facet of government or industrial activities in energy conservaThis report has pointed out in a general way the potential relevance of Second Law analyses. These are neither simple nor routinely used techniques.

tion.

It

is characteristic of the state-of-the-art of development of these tools that the relative benefit/cost of their use should be considered on a case-by-case basis.

[1]. Evans, Robert, A Proof that Essergy is the Only Consistent Measure of Potential Work (for Chemical Systems). Ph.D Thesis, Dartmouth College, 1969.

[2]. Haywood, R. W., A Critical Review of the Theorems of Thermodynamic
Availability, with Concise Formulations--Part 1. Availability, J.
Mech. Engrg. Science, Vol. 16, No. 3, 1974.
ibid, Vol. 16, No. 4, 1974.

Part 2.

Irreversibility,

[3]. Keenan, Jos. H., Availability and Irreversibility in Thermodynamics. British J. of Appl. Physics, Vol. 2, p. 183-192, July 1951.

[4]. Gagglioli, Richard A., and Petit, Peter J., Use THE SECOND LAW, first, CHEMTECH, Aug. 1977.

[5]. Keenan, J. H., A Steam Chart for Second-Law Analysis--A Study of Thermodynamic Availability in the Steam Power Plant. Steam Table Session, Annl. Mtg., 1931, American Society of Mechanical Engineers, N. Y., March 1932.

[6]. Hall, E. H., Hanna, W. T., et al, Evaluation of the Theoretical Potential for Energy Conservation in Seven Basic Industries, Report to Federal

Energy Admin., July 1975, by Battelle, Columbus Laboratories. FEA/D-75/CE1. (PB # PB-244 772).

[7]. Weinberg, Alvin M., Reflections on the Energy Wars. American Scientist, Vol. 66, pp. 153-158, Mar. -Apr. 1978.

[8]. Gyftopoulos, Elias P., and Widmer, Thomas F., Benefit-Cost of Energy Conservation. Sympos. on Theoretical and Applied Thermodynamics; Am. Chem. Soc., Sept. 1978, Miami, Fla.

[9]. Reistad, Gordon M., and Gaggioli, Richard A., Available Energy Costing, Sympos. on Theoretical and Applied Thermodynamics; Am. Chem. Soc., Sept. 1978, Miami, Fla.

[10]. Evans, R. B., Thermo economic Isolation and Essergy Analysis, Workshop-Second Law of Thermodynamics, U.S. Dept. of Energy and Geo. Washington U., Washington, D.C. August 1979.

[11]. Gyftopoulos, Elias P., Availability Analysis:

The Combined Energy and

Entropy Balance. Sympos. on Theoretical and Applied Thermodynamics;
Am. Chem. Soc., Sept. 1978, Miami, Fla.

[12]. Hatsopoulos, G. N., Gyftopoulos, E. P., Sant, R. W., and Widner, T. F., Capital investment to save energy. Harvard Business Review, Vol. 56, No. 2, pp. 111-122, Mar.-Apr. 1978.

[13]. "Efficient Use of Energy", American Institute of Physics

Conference Proceedings No. 25, American Institute of Physics, New York,
Part I, Chapter 2.

[14]. Gaggioli, Richard A. and Wepfer, William J., Exergy Economics,
Presented at the DoE/George Washington University Workshop on the
Second Law, Washington, D.C., August 1979.

A Study of

[15]. Kennan, J. H., A Steam Chart for Second Law Analysis: Thermodynamic Availability in the Steam Power Plant, ASME Transactions 1931.

U. S. GOVERNMENT PRINTING OFFICE: 1980 311-046/197 (265)

U.S. DEPT. OF COMM.

BIBLIOGRAPHIC DATA
SHEET

4. TITLE AND SUBTITLE

1. PUBLICATION OR REPORT NO.
NBS TN 1115

2.Gov't. Accession No. 3. Recipient's Accession No.

A Report on the Relevance of the Second Law of Thermodynamics to Energy Conservation

7. AUTHOR(S)

David Didion, Dave Garvin, Jack Snell

9. PERFORMING ORGANIZATION NAME AND ADDRESS

NATIONAL BUREAU OF STANDARDS
DEPARTMENT OF COMMERCE

WASHINGTON, DC 20234

12. SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street, City, State, ZIP) Department of Energy

Office of Industrial Programs

1000 Independence Avenue, SW Washington, DC. 20585

15. SUPPLEMENTARY NOTES

5. Publication Date

August 1980

Performing Organization Code

742

8. Performing Organ. Report No.

10. Project/Task/Work Unit No.

7424478

11. Contract/Grant No.

13. Type of Report & Period Covered

Final

14. Sponsoring Agency Code

Document describes a computer program; SF-185, FIPS Software Summary, is attached.

16. ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a significant bibliography or literature survey, mention it here.)

This is a study of the relevance to Federal energy conservation programs of the use of the concept of energy efficiency as being the ratio of the minimum available work necessary for accomplishing a given task to the available work in the actual fuel used to accomplish this task. Included within the study is a review of selected elements of thermodynamics and efficiency concepts, and identification of the technology pertinent to energy conservation programs. The study examines the potential benefits, if any, that would accrue from the application of Second Law of Thermodynamics principles to these technologies. Results indicate the positive value of the Second Law analytical techniques in the planning and design stages of system development, and the rather limited value of its use during the performance monitoring stage. Needs for advancing the acceptance and use of the Second Law analytical techniques are identified.

17. KEY WORDS (six to twelve entries; alphabetical order; capitalize only the first letter of the first key word unless a proper name;
separated by semicolons)

Availability analysis; energy, energy conservation; process efficiency,
Second Law of Thermodynamics; system efficiency

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