Solar Power Density cos. Module 10: Solar Energy. Solar Energy (Whr/m 2 /day) Zenith Angle 5/10/2009. Professor Mohamed A. El Sharkawi.

Transcription

1 5/10/009 Mul 10: Slar Enrgy rfr Mham A. El Sharkawi Slar wr Dnity c t : lar pwr nity n arth in kw/m wa p : xtratrrtrial pwr nity (1.353 kw/m ) :znith angl (angl frm th utwar nrmal n th arth urfac t th cntr f th un) t : irct tranmittanc f ga xcpt fr watr (th fractin f raiant nrgy that i nt abrb by ga) p : i th tranmittanc f arl wa : watr vapr abrptin f raiatin. Znith Angl Slar Enrgy (Whr/m /ay) Cntr f Sun Cntr f Earth 1

2 5/10/009 Mling Daily Slar wr Dnity Dnity rati 100% 80% 60% Slar Efficincy () c t wa p ( t t ) 40% 0% 0% Tim t:hur f th ay uing th 4 hr clck : th imum lar pwr nity t : tim at (nntim in th quatr) : tanar viatin c 0 5 % t wa p 70 Exampl An ara lcat nar th quatr ha th fllwing paramtr: t 80%, p 95%, wa % Aum that th tanar viatin f th lar itributin functin i 3.5hr. Cmput th lar pwr nity an lar fficincy at 3:00 M. At nn c t Slutin wa p * kw/m 1353 * c( 0 )*. At 3:00M ( t t ) ( 15 1 ) 1. 0* *( 3. 5 ) kw/m * % c( 0 )* 74

3 5/10/009 Banpa Ml Typ f Slar Sytm ty Slar pwr nit aiv Slar Sytm (Slar thrmal Sytm) Activ Slar Sytm (htvltaic r ) Tim (Day) aiv Slar Sytm aiv Slar Nw upply f cl watr Warm watr t th hu Warm watr Ln Tank Sun ray Cllctr Cl watr back t lar cllctr 3

4 5/10/009 ntgrat Slar Cmbin Cycl Sytm (SCCS) ntgrat Slar Cmbin Cycl Sytm (SCCS) Rcivr Cllctr mirrr StirlingSytm Trugh Sytm 4

5 5/10/009 Silicn Activ Slar Cll (htvltaic ) Empty pac fr xtra lctrn Elctrn Nuclu Silicn Atm Silicn Crytal Silicn Silicn i a g inulatr T mak th ilicn mr cnuctiv lctrically, aitiv (impuriti) ar a (ping) phphru (), which ha 5 lctrn in it utr hll brn (B), which ha 3 lctrn in it utr hll S S S S S S n typ N Matrial S S Elctrn withut bning Extra pac fr lctrn S S S S S S B S S p typ 5

6 5/10/009 Activ Slar Cll () cll i built lik a i ut f micnuctr matrial. Sunlight i cmp f phtn, r particl f lar nrgy. htn ar th nrgy bypruct f th nuclar ractin in th un. Whn phtn trik a cll, m f th prtn nrgy i abrb by th micnuctr matrial f th cll. With thi xtra nrgy, th lctrn in th n matrial bcm xcit an brak ff it atm Activ Slar Cll () Th fr lctrn mv twar th fr hl in th p typ ilicn Thy jin tgthr in th vlum btwn th tw matrial knwn a th pltin zn At quilibrium, th pltin zn crat a barrir that mak it harr fr any mr lctrn t mv int th hl in th p typ Furthr lctrn g thugh xtrnal path t th p matrial. Thi i th currnt that can b rut t xtrnal la Main art f Gla cvr r ln Ln N Typ La Antirflctiv cating Cntact gri n typ matrial Ba Typ p typ matrial Ba 6

7 5/10/009 Structur f Slar Sytm cll: 4X4 inch. Th cll can pruc abut 1 watt which i nugh t run a calculatr. Structur f Slar Sytm anl r Mul: T incra it nrgy rating, th cll ar cnnct tgthr in paralll an ri. aralll cll incra th currnt rating Sri cll incra th vltag rating. Structur f Slar Sytm Array: panl cnnct tgthr in paralll an ri t frm a high pwr ytm. 7

8 5/10/009 Cmputatin f Enrgy Dnity rati 100% 80% 60% 40% Slar pwr nity ( t t ) 0% 0% Tim 8

9 5/10/009 Cmputatin f Enrgy Linar rlatinhip Slar pwr nity anl pwr ( t t ) anl Enrgy E panl 4 0 panl ( t t ) t ( t t ) E panl ( t 1) 1.5 Exampl 100 W Cmput th aily nrgy pruc by a panl. Slutin * * kwh Exampl A m panl f lar cll i intall in th Nvaa ara. Th fficincy f th lar panl i 10% h kw / m 1. Cmput th lctrical pwr f th panl.. Aum th panl i intall n a gynchrnu atllit. Cmput it lctrical pwr utput.. 1. Slutin un * A * panl un 0. 1* * A1353 *. 706 un 706 kw W kw panl un 0. 1* W 9

10 5/10/009 Slar array Hu Stan Aln Sytm Slar array Sytm withut battry Hu c currnt Chargr Dichargr Cnvrtr ac currnt c currnt Cnvrtr ac currnt Mtr T utility Battry Lcal la Lcal la Slar Sytm With Battry Battry: T tr th nrgy whn th pwr i nt fully utiliz by th la. Th battry pwr i latr u whn th pwr i l than th man. Th battri ar p cycl typ Chargr: T charg th battry by th Slar Sytm With Battry nvrtr: T invrt th c pwr f th battry t th 60Hz pwr u in hm. Synchrnizr: U t cnnct th ytm t th pwr gri. DC/AC cnvrtr. 10

11 5/10/009 al Ml: N Junctin Cath (K) Cath (K) Mling f n p An (A) An (A) al Ml: N Junctin + l T 1 kt T q R Rvr bia rgin Frwar bia rgin T : thrmal vltag q: lmntary charg cntant ( Culmb) k: Bltzmann cntant (1.380 x 10 3 J/K) T: ablut tmpratur in Klvin (K). Rvr Bia Currnt + La a - 11

12 5/10/009 Currnt Th rvr bia currnt flw thrugh th i t th la. Th currnt mak th vltag acr th i frwar bia Th frwar bia vltag crat a frwar currnt int th i Slar Cll Ml = La : th lar currnt (i a nnlinar variabl that chang with light nity (irraianc) : th currnt thrugh th i. Charactritic Output wr f = T 1 Q Q Q Q T 1 1

13 5/10/009 Charactritic = Shrt circuit currnt Opn circuit vltag c T Opn Circuit ltag c T *ln 1 1 = c Shrt Circuit Currnt Oprating Charactritic c =0 c = c mp mp c 13

14 5/10/009 Exampl An ial cll with rvr aturatin currnt f 1nA i prating at 30 C. Th lar currnt at 30 C i 1A. Cmput th utput vltag an utput pwr f th cll whn th la raw 0.5A. T Slutin 3 k T 1.38*10 *( ) *10 q *10 T * Ln1 0.5*10 1 * 0.53 T 0.53* W Exampl An ial lar cll with rvr aturatin currnt f 1nA i prating at 0 C. Th lar currnt at 0 C i 0.8A. Cmput th vltag an currnt f th lar cll at th imum pwr pint. Slutin / T T T 1 / T T k T q *10 *( ) 5.5* *10 14

15 5/10/009 mp mp / T 1 T mp / mp 0.8* mp m mp T 1 mp mp A mp * * mp mw Oprating int f Th prating pint f th lar cll pn n th magnitu f th la ritanc R Th la ritanc i th utput vltag ivi by th la currnt. Th intrctin f th cll charactritic with th la lin i th prating gpint f th cll. Oprating int f Exampl R R 1 <R <R 3 R 1 1 R La lin 3 R 3 Fr th lar cll in th prviu xampl, cmput th la ritanc at th imum utput pwr. Slutin Frm th prviu xampl mp mp A c R mp mp R mp 15

16 5/10/009 Effct f rraianc 3 1 < < La lin 1 Effct f Tmpratur T T 1 >T >T 3 T 1 c La lin 1 3 T 1 < < T 3 c Effct f Tmpratur T Mul (Sri Cnnctin) T 1 >T >T 3 T 1 T T = 1 + La La = 1 = 16

17 5/10/009 Mul (aralll Cnnctin) L f Cll (rraianc L) La = 1 + = 1 = La Du t th rflctin f th lar raiatin at th tp f th cll. Th light ha phtn f a wi rang f nrgy lvl Sm n t hav nugh nrgy t xcit th lctrn. Othr hav t much nrgy that i har t captur by th lctrn. Th tw cnari accunt fr th l f abut 70% f th lar nrgy. L f Cll (Elctrical L) Th ritanc f th cllctr trac at th tp f th cll. Th ritanc f th wir cnncting cll t la. Th ritanc f th micnuctr crytal Ral Ml T accunt fr th lctrical l nly Slar Cll R p p R La R : Ritanc f wir an trac R p : intrnal ritanc f th cll 17

18 5/10/009 irraianc Efficincy f Cll Sun pwr cnvrt t lctricity Sun pwr Output pwr f th cll Sun pwr cnvrt t lctricity irraianc ut ut ut * A * * * A Exampl A 100 cm lar cll i prating at 30 C whr th utput currnt i 1A, th la vltag i 0.4 an th aturatin currnt f th i i 1nA. Th ri ritanc f th cll i 10 m an th paralll ritanc i 1k. At a giv tim, th lar pwr nity i 00W/m. Cmput th irraianc fficincy an th vrall fficincy. T k T q Slutin 3.38*10 *( ) 6.1* *10 R * T * ma 0.41 p 0.41 ma R 1000 irraianc R p p A * A 0.41* *0.01 l ut R ut p p Slutin R 1.0 *0.01 ut l *10 * mw l irraianc 0.05* * * Cncluin Mt f th l ar irraianc 18

19 5/10/009 $/kwh Amnt f Sytm $6.0 $5.0 $5.0 $4.0 $3.0 $.0 $1.5 $1.0 $0.6 $0.4 $0.3 $ Yar Slar wr an th Envirnmnt 6kW frm a phtvltaic ytm inta f a thrmal pwr plant can ruc annual pllutin by 3 lb. f NO x (Nitrgn Oxi), 10 lb. f SO (Sulfur Dixi), an lb. f CO (Carbn Dixi). Amnt f Sytm Cnumr pruct (calculatr, watch, battry chargr, light cntrl, an flahlight) ar th mt cmmn applicatin Largr ytm ar xtnivly u in pac applicatin (uch a atllit) n highr pwr applicatin, thr factr trminth th applicability f th ytm 1. th ct an th payback pri f th ytm. th accibility t a pwr gri 3. th iniviual inclinatin t invt in nvirnmntally frinly tchnlgi. Amnt f Sytm n rmt ara withut acc t pwr gri, th ytm i ftn th firt chic amng th availabl altrnativ. By th n f th 0 th cntury, th ytm wrlwi ha th capacity f mr than 900 GWh annually thi nrgy i nugh fr abut 70,000 hm in th USA, r abut 4 millin hm in vlping cuntri. 19

20 5/10/009 Amnt f Sytm T manufactur th lar cll, arnic an ilicn cmpun ar u Arnic i rl an flavrl mi mtallic chmical that i highly txic Silicn, by itlf, i nt txic. Hwvr, whn aitiv ar a t mak th micnuctr matrial, th cmpun can b xtrmly txic. Sinc watr i u in th manufacturing prc, th runff cul cau th matrial t rach lcal tram Shul a array catch fir, th chmical can b rla int th nvirnmnt. Amnt f Sytm Slar pwr nity can b intrmittnt u t wathr cnitin ar limit xcluivly t aytim u Fr high pwr ytm, th array pra vr a larg ara. Th ytm ar cnir by m t b viually intruiv Th fficincy f th lar panl i till lw, making th ytm xpniv an larg Slar ytm rquir cntinuu claning f thir urfac 0