Cooling Degree-days Greece

. . . . ,. 1 2010 Tech. Chron. Sci. J. TCG, I, No 1

161

50 . . .

. . , . 50 . 1983-1992, , , . 20C 28C, 2C .

1. . , , , , . [1] 18.3oC, . , , . : 2.4.2007 : 20.7.2007

( ). , , , , . , , . , , 18.3oC 18.3oC . (Variable base degree-day method) [2], [3]. , , , , , 18.3oC .

2. . , (tbal), , . , , , , , .

162

. . . . , , . 1 2010 Tech. Chron. Sci. J. TCG, I, No 1

( , , , W), (ti) ( , C) (H) (W/K), :

( Q gain )

H ( t i t bal ) Q gain

(2.1)

[kg] Wi = [kgH2O/kg ] Wo = [kgH2O/kg ] [4] hfg = [2500 kJ/kg] ( ):

m = ,

t bal t i

Q gain H

(2.2)

Q c, yr

j

m 1

Q c,mo Q lat,mo

(2.8)

, () to() . :

H Qc [ t o ( ) t bal ] c

tbal < to

(2.3)

() (c) , , , , ( ) . (c) (H) , :

H Qc [ t o () t bal ] d c

(2.4)

(+) . . ( ) DDc(tbal) (tbal) .

DD c t bal t o t bal d

(2.5)

( ) DDc(tbal), :

Q c,mo

H DD c ( t bal ) c

(2.6)

, , , :

Q lat,mo m h fg ( Wo Wi )

(2.7)

j . , , , (tbal), . 24. , ( .. ), . , . , , . , , . . , , . , , . (c) , , , . (c) ( ), :

ss CFp

(2.9)


163

ss = ( ) CFp = CFp [4]: (2.10) RLC = CDD =( tbal)/1000 HUN =( )x100 [5]CFp 1.04 0.0182 RLC 0.0233 CDD + 0.062 HUM

3. , . 30 [6]. 1956-1973 (..) . , 1962-1976. . 18 (1956-1973) .. , 13 (1961-1973). 30 2425/86 [7] . 30 [6] [7] 25C, . [8, 9]. -

1983 1992 [10, 11]. (), [12]. , , [6] [7], , 2C, . , , , , . , , . , , . , . Erbs et al. [13].

4. Erbs et al. [13], ( t o, m ). (yr) (m), :

yr

1 12 2 ( t o,m t o, yr ) 12 n 1

(4.1) (4.2)

m 1.45 0.0290t o,m 0.0664 yr

t o, yr = , [C]. H : ln(e e DD h ( t bal ) m N 3 / 2 2 2

(4.3)

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= 1.698 N = = :

t o,m t bal m N

(4.4)

[%]

[14] 0.1% 11%. 9% . Erbs et al. [13] 48 . , [15, 16].

[6] [7] : () , () () [7] . [6] [7] 20 10 10%, 3 10% 20% 7 20%. 25C, . , . . [6] , 3.5%.50 40 30 20 10 0 -10 -20 -30

5. 50 . 1983 2002 [10,11]. [13] (13 43 , ) [15, 16, 17]. 20, 22, 24, 26 28 C. , . , , , , , . .

1: [6,7] Figure 1 Estimated degree-days deviation from [6,7]

1 (%) 4 , 3.5%, 6.5%, , 25% , 30%.

5. 50 , 20 28C 2C, 2425/86 . .


165

, Erbs et al. 2425/86, 50% 10%, 50% 10%, 55% ( 100%). . .

3.

4. 5.

6. 7. 8.

6. , & , . SOL ENERGY HELLAS A.E. , , .

9. 10. 11.

12. 13. 14.

15.

7. 1. ASHRAE (1985), Fundamentals, American Society of Heating Refrigerating and Air-Conditioning Engineers, Inc., Atlanta, USA. 2. ASHRAE (1993), Fundamentals, American Society of Heating

16. 17.

Refrigerating and Air-Conditioning Engineers, Inc., Atlanta, USA. K.T. (1999), , . 6 , , . 67-76, , . Kusuda T., Alereza T. and Hovander (1982), Development of equipment seasonal performance models for simplified analysis methods, ASHRAE Transactions, 88(2), pp. 249-262. . . (1982), , . 1 , , , . ., . (1982), , . ... 9, . 2425/86 (1987), : . -. K.T. (1999), . , . 6 , , . 23-30 , , . Papakostas K., Kyriakis N. (2005), Heating and cooling degreehours for Athens and Thessaloniki, Greece, Renewable Energy, 30, pp. 1873-1880. Climatological Bulletin (1983-2002), National Observatory of Athens, Institute of Meteorology and Physics of the Atmospheric Environment. , , , , (1983-2002), . Tselepidaki I., Santamouris M. and Melotsiotis D. (1993), Analysis of the summer ambient temperatures for cooling purposes, Solar Energy, Vol. 50, pp. 197-204. Erbs D., Klein S. and Beckman W. (1983), Estimation of Degree-Days and Ambient Temperature Bin Data from Monthly-Average Temperatures, ASHRAE Journal 25(6):60. Papakostas K., Kyriakis N. (2005), Estimation of variablebase heating and cooling degree-day data from monthly average temperatures. Validation of the methodology in two Greek cities, Proccedings of the 36th International HVAC&R Congress, Belgrade, Serbia and Montenegro. .... (1966-1998), o . .... (1966-1998), , , C. ., . (2004), , , , ...

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1: 50 . Table 1: Cooling degree-days in 50 Greek cities for various temperature bases.

(1983-2002) .. 3758 .. 2343 . . 107 m (1960-1999) .. 3838 .. 2125 . 107m .46 m (1966-1998) .. 4051 .. 2552 . 107 m . 2.5 m (1955-1997) .. 3823 .. 2306 . 107 . 110 m (1948-1975) .. 3809 .. 2125 . 107m . 11 m (1948-1975) .. 3811 .. 2029 . 107 m . 2 m (1961-1995) .. 3910 .. 2100 . 107m . 39 m

tbal (oC)28 26 24 22 20t o, m

22 43 73 114 165 25.4 9 23 51 93 146 25.4 24.7 5 13 31 61 105 25.4 23.1 21 48 89 140 197 25.4 26.5 6 17 40 79 129 25.4 24.1 4 11 27 59 105 25.4 23.2 7 17 40 77 127 25.4 24.0

52 86 132 187 247 27.9 26 57 103 159 218 27.9 27.0 16 38 74 123 180 27.9 25.7 71 121 179 239 301 27.9 29.7 21 50 94 149 209 27.9 26.7 11 30 65 115 173 27.9 25.5 20 47 90 144 203 27.9 26.5 44 76 119 174 234 27.5 23 51 96 150 209 27.5 26.7 13 31 64 118 166 27.5 25.2 30 62 109 165 225 27.5 27.2 25 57 105 161 221 27.5 27.1 13 34 72 123 182 27.5 25.8 20 47 90 144 203 27.5 26.5

10 23 44 77 122 23.8 5 12 28 58 102 23.8 23.0 2 6 14 31 61 23.8 21.0 6 14 32 63 108 23.8 23.2 6 15 36 72 121 23.8 4 12 30 64 112 23.8 23.5 5 12 29 59 104 23.8 23.1

129 228 368 552 768 18.0 63 144 278 460 675 18.0 17.2 38 88 183 326 512 18.0 14.9 128 245 409 607 831 18.0 17.3 58 139 275 461 680 18.0 32 87 194 361 572 18.0 18.1 52 123 249 424 637 18.0 17.2

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7 (1976-1988) .. 3922 .. 2257 . 107m . 3 m (1976-1999) .. 3747 .. 2054 . 6.5 . 107 m (1955-1997) .. 3520 .. 2511 . 107 . 38.5 m (1983-2002) .. 4037 .. 2257 . 107m . 31 m (1960-1999) .. 3625 .. 2526 . 208 . 107 m (1956-1997) .. 3500 .. 2545 . 107m . 13 m (1956-1997) .. 3940 .. 2051 . 107 . 483 m (1960-1984) .. 4056

tbal (oC)28 26 24 22 20t o, m

10 24 53 96 148 25.4 24.8 7 19 44 85 137 25.4 24.4 6 18 43 84 136 25.4 24.4 12 26 50 83 125 25.4 23.8 4 12 30 64 112 25.4 23.5 12 31 67 117 173 25.4 25.7 3 8 19 42 78 25.4 21.9 4 10 24 51

29 63 111 167 227 27.9 27.3 24 55 102 158 218 27.9 27.0 17 43 86 140 200 27.9 26.4 31 58 94 140 196 27.9 26.2 10 27 61 110 167 27.9 25.3 37 77 131 190 251 27.9 28.1 11 26 56 100 154 27.9 24.8 10 25 53 95 19 43 84 136 194 27.5 26.2 22 51 97 152 212 27.5 26.8 16 41 83 137 197 27.5 26.3 26 50 84 129 184 27.5 25.9 9 24 55 102 158 27.5 25.0 35 75 128 187 248 27.5 28.0 9 22 48 88 140 27.5 24.3 8 21 45 84

5 14 33 66 112 23.8 23.4 5 13 31 64 111 23.8 23.4 5 13 33 68 117 23.8 23.7 5 12 27 49 82 23.8 21.8 3 8 20 46 88 23.8 22.5 9 25 55 101 156 23.8 25.1 2 4 10 22 46 23.8 20.1 2 5 12 27

63 144 280 465 682 18.0 17.1 58 138 274 459 677 18.0 44 115 245 429 650 18.0 19.1 74 135 254 401 586 18.0 15.6 26 71 167 322 524 18.0 17.8 93 208 381 595 828 18.0 20.0 25 60 133 252 418 18.0 14.3 25 61 134 257

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28 26 24 22

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.. 2424 . 107m . 62 m (1956-1997) .. 3704 .. 2206 . 107 m . 4.5 m (1931-1973) .. 3937 .. 1955 . 107 m . 2 m (1966-1998) .. 4018 .. 2147 . 625 . 107 m (1938-1973) ... 4107 .. 2524 . 107m . 30 m (1932-1940, 1955-1975) .. 4030 .. 2045 . 107 . 542 m (1937-1940, 1947-1974) .. 3756 .. 2257 . 107 . 14.5 m (1955-1997) .. 3608 .. 2300 . 107 . 166 m

tbal (oC)20t o, m

91 25.4 22.5 6 17 40 78 129 25.4 24.1 6 16 39 76 126 25.4 24.0 3 8 19 40 75 25.4 21.7 5 13 31 61 105 25.4 23.1 2 6 15 35 67 25.4 21.4 10 26 56 100 154 25.4 25.0 4 11 27 59 105 25.4 23.2

148 27.9 24.6 18 44 87 141 200 27.9 26.4 20 48 92 146 206 27.9 26.6 9 22 46 85 135 27.9 24.1 19 43 83 134 192 27.9 26.1 10 24 52 95 148 27.9 24.6 35 72 124 182 242 27.9 27.8 13 33 70 121 179 27.9 25.7 135 27.5 24.1 18 43 84 138 197 27.5 26.3 20 46 89 144 203 27.5 26.5 7 17 38 72 120 27.5 23.5 17 39 76 126 183 27.5 25.8 9 23 50 92 145 27.5 24.5 35 72 124 182 242 27.5 27.8 13 33 70 121 179 27.5 25.7

54 23.8 20.6 4 11 28 60 105 23.8 23.2 4 10 26 55 98 23.8 22.9 1 4 8 19 39 23.8 19.4 3 6 15 34 65 23.8 21.2 2 4 11 25 52 23.8 20.5 7 19 42 81 132 23.8 24.2 3 10 24 54 97 23.8 22.9

429 18.0 14.4 46 115 239 417 631 18.0 17.8 50 120 246 421 633 18.0 17.7 21 51 111 217 369 18.0 12.9 44 101 205 355 545 18.0 15.1 23 57 128 247 412 18.0 14.6 87 189 346 545 770 18.0 18.3 33 87 191 355 560 18.0 17.7

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(1960-1990) .. 3838 .. 2406 . 221 . 107 m (1931-1940, 1956-1973) .. 3854 .. 2224 . 107 . 143 m (1955-1997) .. 3908 .. 2225 . 107m . 73 m (1961-1999) .. 3953 .. 2504 . 107 . 12 m m (1955-1997) .. 3650 .. 2143 . 107m . 33 m (1955-1997) .. 3645 .. 2427 . 107 . 182 m (1955-1996) .. 3906 .. 2403 . 107 m . 3 m (1955-1997) .. 3706

tbal (oC)28 26 24 22 20t o, m

4 9 24 51 94 25.4 22.7 12 29 61 106 160 25.4 25.2 12 29 59 102 155 25.4 25.0 5 13 32 65 111 25.4 23.4 3 8 21 48 90 25.4 22.6 5 13 32 67 115 25.4 23.6 5 14 34 69 117 25.4 23.7 3 10 27 59

9 23 52 96 150 27.9 24.7 36 74 124 182 243 27.9 27.8 30 63 110 165 225 27.9 27.2 13 33 68 117 173 27.9 25.5 8 22 51 97 152 27.9 24.8 10 27 59 107 164 27.9 25.2 13 32 68 118 175 27.9 25.6 8 21 51 96 8 21 47 89 142 27.5 24.4 32 67 116 173 233 27.5 21 46 86 137 195 27.5 26.2 11 28 60 106 162 27.5 25.1 12 32 69 120 179 27.5 25.7 9 24 54 100 155 27.5 24.9 10 27 58 105 160 27.5 25.1 7 20 49 94

2 5 13 29 60 23.8 21.1 5 12 29 59 102 23.8 23.0 4 9 20 42 77 23.8 21.8 2 6 16 36 70 23.8 21.6 4 12 31 66 115 23.8 23.6 3 7 19 43 83 23.8 22.3 3 9 22 48 88 23.8 22.5 3 8 21 48

22 58 135 265 446 18.0 15.9 85 182 330 520 738 18.0 17.4 67 147 275 446 652 18.0 15.7 32 80 175 324 517 18.0 16.2 27 74 172 331 536 18.0 27 71 164 317 517 18.0 17.5 31 82 182 340 540 18.0 17.0 21 59 148 297

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.. 2523 . 107 m . 9 m (1960-1981) .. 4130 .. 2631 . 107m . 43 m (1955-1997) .. 3705 .. 2509 . 107 m . 1 m (1955-1997) .. 3815 .. 2144 . 107 m . 1 m (1932-1941, 1943-1975) .. 3767 .. 2243 . 107 . 132 m (1957-1975) .. 3521 .. 2431 . 107m . 16 m (1955-1997) .. 3623 .. 2807 . 107m . 35 m (1978-1997) .. 3742 .. 2655 . 107 . 48.5 m

tbal (oC)20t o, m

106 25.4 23.3 6 16 35 68 113 25.4 23.4 2 7 19 45 87 25.4 22.5 6 17 40 79 129 25.4 24.1 7 18 41 81 131 25.4 24.2 8 22 51 96 150 25.4 24.9 8 21 48 92 145 25.4 24.7 9 23 51 95 148 25.4 24.8

152 27.9 24.8 16 36 71 119 174 27.9 25.5 6 16 40 80 134 27.9 24.2 19 45 87 141 200 27.9 26.4 23 53 99 155 215 27.9 26.9 20 49 95 152 212 27.9 26.8 22 52 99 155 215 27.9 26.9 25 57 105 161 221 27.9 27.1 149 27.5 24.7 12 28 58 101 155 27.5 24.8 6 17 43 85 139 27.5 24.4 21 50 94 149 209 27.5 26.7 25 57 104 161 221 27.5 27.1 21 51 98 154 215 27.5 26.9 24 56 104 161 221 27.5 27.1 22 52 97 152 212 27.5 26.8

92 23.8 22.7 2 6 13 29 57 23.8 20.7 2 6 18 42 82 23.8 22.3 5 13 32 66 113 23.8 23.5 6 16 39 76 126 23.8 24.0 6 17 41 81 133 23.8 24.3 7 20 47 89 142 23.8 24.6 5 14 35 70 118 23.8 23.7

499 18.0 18.2 37 86 177 317 499 18.0 14.5 16 46 120 252 442 18.0 17.8 51 125 253 435 651 18.0 17.9 61 144 283 473 693 18.0 18.2 55 139 285 483 710 18.0 19.6 61 149 298 497 723 18.0 19.1 62 146 287 478 699 18.0 18.4

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(1971-1997) .. 4104 .. 2334 . 107m . 32 m (1935-1943, 1946-1975) .. 3512 .. 2606 . 107m . 25 m (1932-1971) .. 3854 .. 2433 . 107 m . 4 m (1959-1975) .. 3550 .. 2410 . 107 . 151 m (1989-1999) .. 4112 .. 2618 . 107 m . 15 m (1931-1944, 1963-1971) .. 3727 .. 2457 . 107m . 25 m (1976-1999) .. 3933 .. 2146 . 107 . 116 m (1960-1999) .. 3731

tbal (oC)28 26 24 22 20t o, m

9 22 47 86 136 25.4 24.3 7 19 46 88 141 25.4 24.6 5 13 31 65 113 25.4 23.5 6 18 42 82 134 25.4 24.3 7 18 39 74 121 25.4 23.7 6 17 40 80 131 25.4 24.2 14 33 66 112 166 25.4 3 9 21 46

22 48 88 140 198 27.9 26.3 17 42 85 140 199 27.9 26.4 13 32 68 118 176 27.9 25.6 17 42 84 138 197 27.9 26.3 18 40 77 127 183 27.9 25.8 18 45 88 143 203 27.9 26.5 33 67 115 171 231 27.9 27.4 9 22 49 90 15 34 67 114 169 27.5 25.3 18 44 88 143 203 27.5 26.5 11 29 62 110 167 27.5 25.3 15 37 77 129 188 27.5 26.0 17 37 73 121 177 27.5 25.6 16 40 81 135 194 27.5 26.2 22 47 88 140 198 27.5 26.3 7 19 41 79

3 8 19 39 74 23.8 21.6 6 16 39 79 130 23.8 24.2 2 7 17 40 77 23.8 22.0 3 10 25 54 98 23.8 22.9 2 6 14 30 59 23.8 20.8 4 12 31 65 112 23.8 23.5 5 11 26 52 92 23.8 22.5 2 4 9 21

49 112 221 379 577 18.0 15.1 48 121 258 450 673 18.0 19.4 31 81 178 333 533 18.0 17.3 41 107 228 403 617 18.0 18.1 44 101 203 352 540 18.0 14.6 44 114 240 423 640 18.0 18.5 73 158 294 475 686 18.0 16.1 21 54 120 236

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.. 2222 . 107 . 661 m (1961-1979) .. 3500 .. 2445 . 107 m . 7 m (1960-1999) .. 4047 .. 2124 . 661 . 107 m (1960-1975, 1980-1994) .. 3828 .. 2336 . 107m . 4 m (1961-1994) .. 3530 .. 2402 . 107m . 62 m (1955-1997) .. 3820 .. 2608 . 107m . 60 m

tbal (oC)20t o, m

84 25.4 22.2 9 24 54 99 153 25.4 25.0 3 7 15 33 63 25.4 21.0 14 33 68 116 171 25.4 25.6 7 19 45 87 139 25.4 24.5 6 17 40 79 129 25.4 24.1

143 27.9 24.4 30 67 117 175 236 27.9 27.6 7 17 37 71 118 27.9 23.4 33 69 119 176 236 27.9 27.6 18 45 88 143 203 27.9 26.5 19 45 87 141 200 27.9 26.4 129 27.5 23.9 27 60 109 167 227 27.5 27.3 5 13 28 56 98 27.5 22.6 32 67 116 173 233 27.5 15 39 79 132 191 27.5 26.1 15 37 76 127 185 27.5 25.9

45 23.8 20.0 7 18 42 82 134 23.8 24.3 1 3 6 13 28 23.8 18.4 8 19 43 82 132 23.8 24.2 4 11 28 61 107 23.8 23.3 4 10 24 52 94 23.8 22.7

401 18.0 14.1 73 169 322 523 750 18.0 19.1 16 40 86 173 307 18.0 12.1 87 188 346 547 772 18.0 18.1 44 114 240 423 640 18.0 18.5 44 109 227 399 608 18.0 17.3

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, , , 487, 541 24 , [email protected]. , , , 487, 541 24 , [email protected] , , , 487, 541 24 , [email protected].


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Extended summary

Cooling Degree-Days for 50 Greek CitiesK. PAPAKOSTAS Lecturer AUTh G. TSILINGIRIDIS Assistant Professor AUTh N. KYRIAKIS Associate Professor AUTh

Abstract The purpose of this study is to determine and present cooling degree-day data, for various base temperatures and for 50 Greek cities. The degree-day data for Athens and Thessaloniki were calculated with the use of hourly dry bulb temperature records from the meteorological stations of the National Observatory of Athens and of the Aristotle University of Thessaloniki. Due to the lack of hourly or daily temperature data for the other 48 cities, a reliable model was adopted for the estimation of the cooling degree days for them. The degree-day data were calculated for every month of the heating period and for base temperature from 20C to 28C step 2C. The results are presented in tabular form and can be used for the estimation of the required cooling energy of buildings, according to the variable base degree-day method.

The variable base degree-base method results in more accurate estimations of the cooling energy required.

2. THE VARIABLE BASE DEGREE-DAY METHODThis method is a generalization of the traditional degreeday method. The concept remains the same but it counts degree-days based on the balance-point temperature, which is defined as the outdoor temperature at which the building requires neither heating nor cooling. The balance point temperature is calculated by taking into account the indoor design air temperature of the building, the total heat gains (occupants, lights, equipment, sun) and the total heat-loss coefficient of the building. For cooling purposes the method recognizes that the total heat gains provide heat down to the balance-point temperature, which may vary from one building to another and from one location to another. Above this temperature the energy consumption for sensible cooling is proportional to the cooling degree-days with a base equal to the balancepoint temperature. Except the energy consumption for sensible cooling, the energy consumption due to the latent load of the outside air should be calculated. This is achieved by taken into account the monthly humidity ratio of the outside air and the total monthly air exchange of the building.

1. INTRODUCTIONDegree-day methods are the simplest procedures for energy analysis of buildings. They are appropriate in cases where the building use and the efficiency of the HVAC equipment can be assumed as relatively constant. The degree-day methods are capable to provide simple and quick estimations of the heating and cooling requirements, on a monthly or seasonal base, especially in residential and light commercial use buildings. Furthermore degree-days are useful in studying quickly optimal design of a building and in comparing energy requirements from one location to another. To the same aim, specialized and expensive computer programs can be used, requiring however significantly more detailed data, usually not available. Degree-day methods thus continue to be of importance. The traditional degree-day method is based on a combination of theory and empirical observations and assumes that, on a long-term average, solar and internal gains will offset the heat losses of a building, when the mean daily outdoor temperature is 18.3C. In such a case, the energy consumption will be proportional to the difference between the mean daily temperature and 18.3C. However, experience has indicated that the so calculated energy requirements were overestimated.Submitted: Apr. 2, 2007 Accepted: July 20, 2007

3. AVAILABILITY OF DEGREE-DAY DATA IN GREECECooling degree-days for various base temperatures have been published for 30 Greek cities. They have been calculated only for the base temperature of 25C. The calculations were based on hourly temperature data for the cities of Athens (period 1956-1973) and Larisa (period 1962-1976) and on correlation techniques for the rest of the towns, due to the

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lack of hourly data. These values of degree-days have been incorporated in the Greek technical regulations and they are used by the engineers for energy calculations. Commenting on the quality of these data, it should be mentioned that: (a) they are outdated, since they are based on temperature measurements up to 1976, (b) the are calculated only for one base temperature and (c) the are not calculated on a monthly basis. Aim of this paper is to provide degree-day data for 50 cities, based on the most recent dry bulb temperature available data and with a step of 2C.

records for the purpose of estimating cooling degree-days. The degree-day data for Athens and Thessaloniki were calculated with the use of hourly dry bulb temperatures records from the meteorological stations of the National Observatory of Athens and of the Aristotle University of Thessaloniki (period 1983-1992). These data were also used for the verification of the reliability of the model and it was found that the estimation results are of a good quality.

5. RESULTS 4. A MODEL FOR ESTIMATING VARIABLE -BASE DEGREE-DAY DATASeveral researchers have proposed formulas for estimating degree days relative to an arbitrary base, when detailed data are missing. Among them Erbs et al. have developed a model based only on the long-term average temperature for each month of the year. In this paper the Erbs methodology was adopted for the estimation of monthly cooling degree-days for 48 Greek cities. The necessary data were taken from records of the Hellenic National Meteorological Service which are published in the Monthly Statistical Books of the Hellenic National Statistical Service. These data were averaged over the years available for each city with 10 or more years of data Variable-base cooling degree-day data for 50 Greek cities are presented in this paper. The degree-day data were calculated for every month of the heating period and for temperature bases from 20C to 28C, using a temperature step of 2C. The results are presented in tabular form and serve for the estimation of the required cooling energy of buildings, according to the variable base degree-day method. It is hoped that the availability of these data will fill the gap in information needed by building designers and engineers for simplified cooling energy calculations for buildings in Greece. The wide range of cities covered in this analysis will also help conducting energy analysis and evaluating different design alternatives for the respective locations.

Konstantinos Papakostas Lecturer AUTh, Process Equipment Design Laboratory, Mechanical Engineering Department, POB 487, 541 24 Thessaloniki, [email protected] Georgios Tsilingiridis Assistant Professor AUTh, Process Equipment Design Laboratory, Mechanical Engineering Department, POB 487, 541 24 Thessaloniki, [email protected] Nikolas Kyriakis Associate Professor AUTh, Process Equipment Design Laboratory, Mechanical Engineering Department, POB 487, 541 24 Thessaloniki, [email protected]

Cooling Degree-days Greece

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