Network extension is an issue in planning district heating systems, specially in a large town; the optimal network does not necessarily connect all the buildings, because of technical and economical reasons. The selection of areas to be connected should be made during the design process, since further variations in the topology are usually difficult and conduct to a non-optimal configuration. This paper deals with the optimal extension of the district heating network using economic criteria. The algorithm here proposed is based on the application of thermoeconomics, together with some concepts derived from the optimization technique called simulated annealing. The algorithm reduces significantly the time required for solving the problem with respect to other optimization techniques such as genetic algorithms. An initial superstructure connecting all the possible users is built. Then the structure is progressively simplified, until the optimal configuration is found. The procedure is applied first to the actual district heating network operating in Turin. The application to a small portion of the central urban area of Turin, at the moment not connected with the DH network. is also proposed. Some general considerations about the optimal network configuration are then obtained by varying the climatic data, the volume of the buildings in the considered area and the distribution of users throughout this area.

1.
Frangopoulos
C. A.
,
von Spakovsky
M. R.
,
Sciubba
E.
. (
2002
).
A Brief Review of Methods for the Design and Synthesis Optimization of Energy Systems
.
The International Journal of Applied Thermodynamics
. Vol.
5
, No.
4
. pp.
151
160
.
2.
V. Verda (2001). Thermoeconomic Diagnosis of an Urban District Heating System Based on Cogenerative Steam and Gas Turbines, Ph.D. Thesis, Politecnico di Torino and University of Zaragoza.
3.
Frangopoulos
C. A.
,
Dimopoulos
G. G.
(
2004
).
Effect of reliability Considerations on the Optimal Synthesis, Design and Operation of a Cogeneration System
.
Energy
,
29
, pp.
309
329
.
4.
D. Rancruel, M.R. von Spakovsky (2004). Investigation of the Control Strategy Development using an Integrated Model of a SOFC based APU under Transient Conditions. ASME Paper IMECE2004-62374.
5.
M. Li, F. Mare´chal, M. Burer, D. Favrat (2004). Multi-criteria Optimization of an Advanced Combined Cycle Power Plant Including CO2 Separation Options. Proceedings of ECOS 04, Guanajuato, Mexico.
6.
Bejan
A.
,
Lorente
S.
(
2004
).
The Constructal Law and the Thermodynamics of Flow Systems with Configuration
.
International Journal of Heat and Mass Transfer
. Vol.
47
, pp.
3203
3214
.
7.
V. Verda, M. Cali`, C. Ciano (2004). Thermoeconomic Synthesis of District Heating Networks. ASME Paper IMECE2004-61448.
8.
A. Bejan, G. Tsatsaronis, M. Moran (1996). Thermal design and Optimization. Wiley. New York.
9.
H.P.Schwefel (1994). Evolution and Optimum Seeking. Wiley. New York.
10.
Metropolis
N.
,
Rosenbluth
A.
,
Teller
A.
,
Teller
T.
(
1953
).
Equation of State Calculations by Fast Computing Machines
.
Journal of Chemical Physics
, Vol.
21
, No.
6
, pp.
1087
1092
.
11.
V. Verda, C. Ciano (2005). A Simulated Annealing Procedure for the Optimal Configuration of District Heating Networks through Thermoeconomics. Proceedings of ATC05, Heperkan, Kesgin, Ozkan Ed. Istanbul, Turkey.
12.
Lozano
M. A.
and
Valero
A.
(
1993
).
Theory of the Exergetic Cost
.
Energy
, Vol.
18
No.
9
, pp.
939
960
.
13.
Valero
A.
.,
Lozano
M. A.
,
Mun˜oz
M.
(
1986
).
A general Theory of exergy saving I, II, III
.
AES
Vol.
2–3
. ASME Book H0341C, pp.
1,9,17
1,9,17
.
14.
Chandrashekar
M.
,
Wong
F. C.
(
1982
).
Thermodynamic System Analysis - A graph-theoretic Approach
.
Energy
, Vol.
7
No.
6
, pp.
539
566
.
15.
R.J. Wilson (1996). Introduction to Graph Theory. Longman, Harlow.
16.
M. Cali`, R. Borchiellini (2002). District Heating Network Calculation and Optimization. Encyclopedia of Life Support Systems, UNESCO (paper 3.19.3.8).
17.
Tsatsaronis
G.
,
Winhold
M.
(
1985
).
Exergoeconomic Analysis and Evaluation of energy-conversion Plants - I. A new general Theory
.
Energy
, Vol.
10
N.
1
, pp.
69
80
.
18.
Verda
V.
,
Borchiellini
R.
,
Cali`
M.
(
2001
).
A thermoeconomic approach for the analysis of district heating systems
.
The International Journal of Applied Thermodynamics
. Vol.
4
, No.
4
. pp.
183
190
.
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