Development of a solar cooker in Brunei Darussalam

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Re~wa61eEner9y,V01.7, N0. ~ pp. 419-4~, 1996 C0pyr19ht • 1996H~v~r 5dence Ltd Pf1n~d ~ 6 ~ 8r1ta1n. A11r19~5 ~ r ~ d PP1 : 50960--1481(96)00013--4 0 9 6 ~ 8 1 ~ 6 $15~0+~00

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8 a n d ~ 5ef1 8e9awan 2028,

(Rece~ed 15 Decem6er 1995 ; accepted 6 March 1996) A65tract--A pr09ram t0 d e v d 0 ~ te~ and ev~uate a 501ar c00ker wa5 carr1ed 0ut w1th the pr1mary 0~ect1ve 0f k5 5u1ta6111ty a5 an ~ r n a t 1 v e mean5 0f c00k1n9 u~n9 5un ray5. Fact0r5 c0n~dered 1n the ev~uat10n 0f the 50hr c00ker 1ndude the m a ~ m u m ~mperature atta1ned, t1me taken t0 6~1 r1ce, t1me taken t0 c00k a vaf1~y 0f Ma1ay d15he5, ea5e 0f u5e, p0rta6111ty, matef1~ c0~ and ea5e 0f manufacture. 1n1t1a11y a 60x type 501ar c00ker wa5 devd0ped u51n9 1mpr0v15ed m a t e r 1 ~ 7he ev~uat10n 0f the 50hr c00ker 6a5ed 0n the ~ re5u1~, the ~a~6111ty and p05h61e m0d1f1cat10n 1n the de~9n t0 1mpr0ve the eff10ency ~ d15cu~ed. C0pYr19ht • 1996 E15ev~r 5dence Ltd

1N7R0DUC710N C00k1n9 w1th 50~r ener9y 15 0ne 0f the m05t eff1dent U~e5 0f 501ar p0we~ 1t 15 Cheap C0mpared w1th 0ther f0rm5 c fc00k1n~ and 15 6enef1C1a1 f0r area5 w1th a6undant 5un5h1ne. 7he need f0r 501ar c00k1n9 159reater than f0r 501ar water heat1n9 f0r m05t 0fthe 5Cattered p0pu1at10n 0fthe deVd0p1n9 C0untr1e5. 5ever~ type5 0f c00ker5 have 6een deve10ped t0 date. 7he5e C00ker5 are 6r0ad1y d1~ded 1nt0 tW0 type5: a c0ncen~at10n type [1-4] and a h0t 60x type ~ - ~ . 1n the c0ncen~at10n type C00keL para60101d 0r 5pher01d ref1ect0r5 are u5ed, w1th the c00k1n9 p0t p1aced at th0r 5un ray f0C~ p01nt. 1n the h0t 60x type 50~r C00keL the d1rect and d1ffU5e rad1at10n enter5 d1rect1y thr0U9h the ~a55 w1nd0w; 1n add1t10n, rad1at10n 15 ref1ec~d ~ 0 m the ~de ref1ect0r. 1n the pre5ent ~udy a 60x type 501ar C00ker w1th a ref1ect0r ha5 6een devd0ped and 1~ perf0rmance exam1ned.

DE~6N AND W0RK1N6 0F 7HE 50LAR C00KER 0 u r 60x type 501ar c00ker 15 a d0u61e-wa11ed 60x 1.e. a 60x w1th1n a 60x, c0ntMn1n9 a 1ayer 0f 1n5u1at10n 0f a60ut 5 cm 1n th1ckne55 6etween the 60xe~ Var10u5 1mpr0v15ed mater1M5 were u5ed 1n the c0n~ruct10n 0f the 501ar c00keL 5uch a5 p~w00d, pre55w00d, card60ard, # a ~ , Mum1num f011, 1n5u1at10n and 0ther mater1M5 a5 5h0wn 1n F19. 1.7he t0p 0fthe 60x wa5 c0vered w1th a dear w1nd0w #a55. A ref1ect0r wa5 a~ached t0 the 501ar c00ker wh1ch c0u1d 6e adju5ted t0 any an#e w1th the hdp 0f tw0 ~0~ed h1n9e5 0n 0ther f1de 0f the 60x. 7he 1n~f10r 0f the 60x wa5 pMnted w1th du11 61ack pMnt and then c0vered w1th the Mum1num f0f1 t0 ~an5mk the max1mum 5un ray5 10 the c00k1n9 p0t p1aced 1n~de the c00ker. 7he 0uter 5urface 0f the c0ntMner wa5 pMnted w1th du11 61ack pMnt f0r m a ~ m u m a650rpt10n 0f rad1at10~ When the 50hr c00ker wa5 phced 1n the 5un, the 6hckened f00d c0ntMner ~00k1n9 p0 0 5tarted a650r61n9 the 5un ray5 c0m1n9 thr0u9h the # a ~ c0ver. 7he ~mperature 1n~de 6e9an r1~n9 rap1d~, 6ecau5e the 1ntake 0f ener9y wa5 9reater than the 1055 0f heat. H0weveL after a 5h0rt t1me the e4u1116r1um ~mperature wa5 reached w~h1n the 60x 1n wh1ch the c00k1n9 p0t (a150 61ackened) wa5 419

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F19. 1. 501ar c00ker (a) w1th0ut ref1ect0r, (6) w1th ref1ect0L pNced w1th the f00d materM. 7he am0unt 0f 1nc1dent ener9y wa5 1ncrea5ed 6y the ref1ect0r, wh1ch c0u1d f0cu5 an add1f10nM am0unt 0f 50Nr ener9y 1nf1de the 60x. 7he 501ar c00ker wa5 1n9M~d at the r00f 0f the Depa~ment 0f Phy5~5 and R5 perf0rmance wa5 ~ud1ed. PERF0RMANCE 0F 7HE 50LAR C00KER

7he perf0rmance 0f the C00ker wa5 mea5ured expermen~1~ f0r a per10d 0f a ~w m0nth5 ~ 8andar 5er 8e9awan. 7he am~ent (7a), c00~n9 p0t (7p) and ~ r 0 r (70 ~mperature5 0f the

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c00ker were mea5ured and p10tted 1n F19. 2.7e5~ were c0nducted under d1fferent c0nd1t10n5 wh1ch 1nduded mea5urement5 0f ~mperature5 w1th and w1th0ut the ref1ect0~ 1t wa5 n0ted that the temperature 1n the c00ker reached 130°C. A num6er 0f d1fferent 10cM d15he5 were c00ked wh1ch 1nduded f1c~ f15h, ve9eta61e5, p0tat0e5, e995 and cake5. 7he m a ~ m u m 1n~f10r and c00k1n9 p0t ~mperature5 rec0rded were 1n the ran9e 0f 8998°C and 87-98°C, re5pe~N~y. RE5UL75 AND D15CU5510N 7he mMn 0~cct1ve 0f th15 attempt wa5 t0 devd0p a 50~r c00kcr a5 an aRcrnat1ve mean5 0 f c 0 0 ~ n 9 f0r pe0~e ~ n 9 1n ~m0te area5 0f 80rne0, whcre dcc~1c1~ 15 5t111n0t ava11aMe. 7he m~0f1~ 0f pe0#e ~ the5e arca5 arc ~rmer5 and f15hermen wh0 u ~ c0nvenf10nM fud5 f0r c 0 0 ~ n ~ 7he c00ker de519ned 15 f1m~e, ea5y t0 u5e and cheapcr than th05e rc4u1f1n9 c0nvent10na1 ener9y. 1t c05t5 appr0~mMe~ 8$ 45.00 (U5$ 33.0~. 1t ~ ~ 5 t 1 n 9 t0 n0te that the c00ker wa5 made u51n9 1 m p r 0 ~ d matef1M5 5uch a5 ~ y w 0 0 ~ p ~ w 0 0 d , card60ard, #a55, Mum1num f011, ~5~af10~ etc. Ad~t10na11L a ~ a n c #a55 m1~0r wa5 u5ed a5 a ref1cct0r 1n5tead 0f a p0115hed m~M 5heeL 70 make 1t ec0n0m1ca11y ~aMe, the ~f1ect0r p 0 ~ n 0f the c00ker 15 manua11y a~u5~Me f0r ~ a d n 9 the 5un. C0nce~ed eff0rt5 are 6dn9 madc t0 ~ 0 d u c e the c00ker 1nt0 the m a r k ~ thr0u9h 10cM a9en~. 7he c00ker ~ p0~aMe and w~9h5 M55 than 3 k9.7he c00~n9 t1mc depend5 0n 5~ar 1ntenf1~ and

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1n9 that the c00ker ha5 p0~nt1~ a5 an aRernaf1ve mean5 0f c00k1n9 1n the c0un~y. 7he t1me 0f c00k1n9 w1116e reduced f19n1f1canf1ydur1n9 the dry 5ea50n. 1n the pre5ent pr0ject, c0nden5at10n wa5 065erved 0n the 1nter10r 5urface 0f the 91a55 p1aced at the t0p 0f the c00ker t0 trap 501ar rad1at10n. 7h15 15 6ecau5e the 0pen1n9 0f the c00ker wa5 pr0v1ded thr0u9h the 511d1n90f the 91a55 5heet. 7h15 can 6e 0verc0me 6y 5ea11n9the 91a55 pr0pedy and hav1n9 the c00ker 0pen1n9 ~0m e1ther waH. C0NCLU510N5 7hc 50hr c00kcr ~ p011ut10n-frcc and can a ~ n a ~mpcraturc 0f 100°C w1th0ut any 10ad 0r rcf1cct0~ A ~mpcraturc 0f 130°C wa5 rcc0rdcd u51n9 thc rcf1cct0r. 1t can c00k a var1cty 0f 10c~ d15he5. 7hc c00kcr 15 p0~a61c and 5tack5 w~1. 7he c00k1n9 t1mc var1c5 w1th ~1maf1c c0nd1t10n5, h0ur5 0f 5un5h1n~ typc and 4uant1ty 0f f00d~ t1me 0f day, ~c. A~u5f1n9 thc f1~ an~c 0f thc rcf1cct0r ~c5uh5 1n h19hcr ~mpcraturc5 wh1c~ c 0 ~ c 5 p 0 n d 1 n ~ redu~c5 thc c00k1n9 t1mc. 1t 15 ca~cL ~cancr and 5a~r t0 c00k f00d 1n the 501ar c00kcr than 1n c0nvcnf10n~ ~0vc5. 7hc c00k1n9 d0c5 n0t need ~nd1n9. 7hcrcf0rc, h0u5cw1vc5 can pcrf0rm 0thcr ch0re5 wh1M the f00d 15 6~n9 c00kcd 1n the 50hr c00ker. 7hcrc ~ n0 ~ a r 0f 6urn1n9 0r 0vc~c00k1n9 ~ thc p0t 15 ~f1 1n the c00kcr f0r 5evcr~ extra h0ur5. H0wcver, 1t 15 5u99c5~d that the 5hapc 0f thc c00ker 6e m0d1f1cd 1n 5uch a way that a 9rcatcr arca 0f thc c00kcr 15 cxp05cd t0 501ar rad1at10n thr0u9h0ut thc day. 7h15 w111 ~ve a h19hcr ~mpcraturc and rcducc thc c00k1n9 f1mc. 1t can 6c ach~vcd 6y mak1n9 the ~dc5 0f thc c00kcr wcd9cd 0ut 1n 0rdcr t0 1ncrca5c thc 501ar c011cct1n9 arca. REFERENCE5

1. J. A. Duff1e, 6 . 0. 6 . L0f and 8. 8eck, La60rat0ry and f1dd ~ud~5 0f p1a5t1c ref1ect0r 50~r c00ke~ Pr0c. Un1tedNat10n5 C0nf, New 50urce5 0f Ener9y, 5, pp. 339-345, R0me (1961). 2. 6 . 0. 6 . L0f and D. A. Fe5~L De~9n and perf0rmance 0f f01d1n9 um6re11a-type 501ar c00keR. Pr0c. Un1tedNat10n5 C0nf, New 50urce5 0f Ener9y, 5, pp. 347-352, R0me (1961). 3. 7. E. 8r0wn and H. 8 ~ , 501ar c011ect0R, Rep0~ N0. CREA-78-1, F10r1da U.5.A. (1978). 4. C. E. 0keke and C. 1. E~kMach1, De519n, c0n5~uct10n and character12at10n 0f 50~r c0ncentrat0r ~ 0 0 k e 0 u~n9 10ca11y avN~61e mater1M5. Ener9y 6, 885-887 (1988). 5. H. P. 6ar9, H. 5. Mann and K. P. 7 h a n ~ , Perf0rmance evNuat10n 0f f1ve 501ar c00ke~. Pr0ceed1n95 0f15E5 C0n9re55, 1nd1a, pp. 1491-1496, F. de W1n~r and M. C0x (Ed~. Per9am0n, 0xf0rd, U.K. (1978). 6. R. C. Wareham, 7he 5un~0ve. Renewa6~ Ener9y 5, 477-478 (1994). 7. 5. M. A. 16rah1m and M. K. E1-R~dy, 7he perf0rmance 0f a 501ar c00ker 1n E9ypt. Renewa6~ Ener9y 5, 2442 2447 (1994).