Profit maximization with Renewable Energy Sources in Generation Mix

Transcription

1 16h AIOAL POWER SYSEMS COFERECE, 15h-17h DECEMBER, Prof maxmzaon wh Renewable Energy Sources n Generaon Mx Yajvender Pal Verma and Ashwan Kumar Absrac-Wh rsng energy demand and growng envronmenal concerns worldwde he renewable energy sources such as wnd, solar s geng major aenon for her ncluson n o he generaon mx. he uncerany and varably wh wnd may resul n economcal and echncal problems n he power sysem. ha s why o compensae for wnd nermency, generaon resources such as gas plan, pumped sorage un ec. are employed due o her lesser sar up me, lower operang cos and good rampng capables. hs paper proposes a model whch nvesgaes he combned operaon of hermal, wnd and pumped sorage uns for he prof maxmzaon n varyng wnd, load, and prce scenaros. he opmal sze of he pumped sorage un o be used has been obaned afer pung he sysem o dfferen condons such as varyng wnd power scenaro, mposng ax on emsson above a lm and ncreasng rampng lms of hermal uns. he model has been appled on IEEE-3 bus es daa and sasfacory resuls have been obaned for opmal hybrd sysem operaon.. Index erms: Hybrd Sysem, Wnd Power, Pumped Sorage. Ls of symbols A. Se: Se of ndces of he hermal uns Se of me nervals (hours) B. Parameers and consans: a,b,,c Cos coeffcens of hermal un Pmax, Maxmum generaon of un a hour Pmn, Mnmum generaon of un a hour SH,, Shu-down cos of un a hour SC, Sar-up cos of un a hour α, β,γ Emsson coeffcen of hermal un D Demand on sysem a hour US, Up-reserve conrbuon of hermal un a hour DS, Down-reserve conrbuon of hermal un a hour SR Sysem up-spnnng reserve requremen whou wnd r % Percenage of oal acual wnd power generaon d % Percenage of maxmum un capacy UR Ramp-up rae for hermal generaor DR Ramp-down rae for hermal generaor Wr Vc Vr Vo V, mn, max, WECS raed oupu; Cu n wnd speed; Raed wnd speed; Cu ou speed. Wnd Speed a hour for un Mnmum value of generaon by pumped sorage un n MW a me. Maxmum value of generaon by pumped sorage un n MW a me. Y.P.Verma s wh Deparmen of Elecrcal & Elecroncs Engneerng a UIE, Panjab Unversy, Chandgarh. Inda. (E-mal: yajvender_verma@yahoo.com) Ashwan Kumar s wh he Deparmen of Elecrcal Engneerng, aonal Insue of echnology Kurukshera, Haryana, Inda. (E-mal: ashwa_ks@yahoo.co.n). 1 mn, 1 max, Mnmum value of power used o pump he waer n me n MW. Maxmum value of power used o pump he waer n me n MW PL mn, Mnmum reservor level a me. PL max, Maxmum reservor level a me PL o Inal reservor level PL Fnal reservor level Prce Elecrcy Prce n dollars h Generaon effcency of pumped sorage un p Pumpng effcency of pumped sorage un M me sep C. Varables: Rev oal revenue generaed OC (*) Operang cos funcon of hermal uns Pw oal wnd power oupu a hour by all uns n MW; P, Power generaed (MW) by hermal un n me EmC, Emsson value of un a hour n lb per hr Cos oal sysem cos n $ /hr PL Pond level a dfferen me nervals Power generaed by pumped sorage un n MW a hour 1 Power used for pumpng waer n MW a hour D. Bnary Varables: U, Un saus O or OFF 1. IRODUCIO here s an exponenal rse n he nsalled capacy of renewable energy sources worldwde n he pas few years. he am s o deploy less carbon nensve and more susanable elecrcy sources n he generaon mx, hereby reducng cos of operaon and emsson generaon. hermal power s ndspensable par of he generaon mx as mees he major par of energy demand worldwde. Bu also causes a major problem o he envronmen by emng harmful gases. he resources (Coal, ol ec) are lmed and hey are depleng day by day. Hence he need s o reduce dependence on non-renewable sources and enhance cleaner renewable energy sources n o he generaon mx. he Kyoo Proocol, Copenhagen summ have also made he emsson reducon mandaory o all counres. As a consequence wnd power n parcular has ganed huge boos. he varably and uncerany lnked wh wnd energy presens challenges for negrang large quanes of wnd relave o radonal generaon echnologes. he large peneraon of wnd power may cause flucuaon and hence pumped sorage (PS) uns are essenal whch can ake care of he msmach beween generaon and demand. he pumped sorage uns can provde back-up for defc power durng low wnd condons and sore waer for fuure usage durng heavy wnd or low load condons. hey can also ac as reserve durng low demand perods and hus avods he commmen of addon un. he suably of he pumped sorage uns s because of s nsan avalably and leas sar up cos besdes beng a Deparmen of Elecrcal Engneerng, Unv. College of Engg., Osmana Unversy, Hyderabad, A.P, IDIA.

2 16h AIOAL POWER SYSEMS COFERECE, 15h-17h DECEMBER, cleaner source of energy. ha s why hydro/pumped sorage uns are one of he bes opons whch are consdered o mee he uncerany due o wnd and load demand. he operaonal sraeges o enhance he wnd power economc gans n hours ahead operaon by ulzaon of waer sorage ably was proposed by [1] [2]. One such sysem was solved by [3] usng Adapve Parcle swarm opmzaon for varyng wnd and load condons. Waer sorage capables of pumped sorage uns were demonsraed wh a combnaon of hydro-hermal uns [4]. he echncal capables of hermal generaon sysem for balancng wnd power were nvesgaed along wh he mpacs of wnd on hermal un commmen. he assessmen of he benefs of wnd power predcon on operang cos and emsson savngs were demonsraed n[5]. he overesmaon and underesmaon of wnd can also affec he dspach. A case sudy was presened by [6] akng wo convenonal and wo wnd power generaors where he sochasc wnd speed characerscs were used by Webull probably densy funcon. Ref. [7] appled SA (smulaed annealng) o he wnd-hermal schedulng consderng addonal physcal and operaonal consrans o reach a compromse beween he sysem secury and operang cos. Schedulng hrough scenaro generaon echnque was preferred over keepng reserves o manan he secury of he sysem nac durng volaly as he reserves are no always suffcen o mee he requred ramp rae a he me of need [8]. he mul-objecve problem formulaon such as operang cos, relably, envronmenal mpac and cusomer preferences ec., were used o fnd Pareo-opmal soluons by [9] [1]. One of he objecves ncluded n he problem formulaon s he envronmenal emsson cos. I s essenal o analyze he effecs of wnd power on emsson from generaon plans under any sysem before makng a schedule for he dspach. I has been found ha he amoun of emsson ha akes place durng sarng and hgh ramp rae condons s also que sgnfcan as compared o he emsson reduced because of he wnd power negraon no he generaon mx [11]. Hence PS uns n hese suaons can no only avod sarng of addonal uns bu also can ake care of hgh ramp rae requred o mee he sysem volales. he dfferen aspecs of un commmen problem n convenonal uns wh wnd power were addressed hrough sochasc programmng and scenaro reducon echnques whch nclude sysem secury/reserve managemen [12], marke ssues lke opmal bddng [13] and beer schedule han deermnsc soluon for operaonal cos and reserves [14]. he objecve of he paper s o develop a model for prof maxmzaon and o fnd he opmal sze of renewable for n a hybrd sysem. he varable naure of wnd s consdered by obanng he dfferen scenaro hrough neural nework echnque. he IEEE-3 bus es sysem daa have been o oban he opmzed operaon of PS uns along wh wnd n varyng elecrcy prce condon. he resuls show ha he pumped sorage un caer o wnd and load unceranes and maxmzes he revenue. he model has been solved for dfferen capaces of PS and wnd un wh dfferen sysem condons. he opmal sze of PS un when beng negraed n a gven sysem can be obaned from he model. II PROBLEM DESCRIPIO here s ncreased compeveness n he elecrcy marke and he problem of mbalances due o wnd power can resul huge revenue loss o Generaon Company. I s no only he mbalances bu also hgh emsson whch can nve penales o he generaon companes. he emsson s hgh durng sarng of un and should be avoded o sar a un for small flucuaon. Moreover here s hgh reserve requremen when sgnfcan wnd power s conneced o he power sysem. Hence o compensae he wnd power varaon and reduce emsson durng volale condons he pumped sorage uns can be que effecve. hs model was developed keepng hese facors n mnd whch wll mprove he oupu conrollably of he wnd generaon. he opmzaon problem helps n deermnng he schedule of generaon of varous uns (on/off) durng each nerval of he schedulng perod for prof maxmzaon when operaed wh wnd-ps sysem n varyng load condons. he objecve funcon encourages he use of pumped sorage uns wh varyng wnd condons n hybrd sysem. I res o opmze he operaonal benef expressed as he dfference beween marke ncomes mnus varable operang cos. he npus o he opmzaon problem are cos and emsson characerscs of hermal uns, wnd power predcon or scenaros durng operang nervals, load demand, acve prce for sellng o he grd and pumpng operaonal cos. he followng secon descrbes he componens of he model one by one. A. hermal Un s Cos and Emsson Characerscs he varable cos (.e. fuel, repar and manenance ec) assocaed wh hermal uns s expressed as quadrac cos curve gven n equaon (1) below: OC ( P +, 2, ) = a + b * P, c * P (1) Where a, b, c, are he cos coeffcens of hermal un. P, s he real power generaon. he sar-up cos of he hermal uns depends upon he me he un has been off pror o sar up. he sar-up cos s gven by he followng exponenal cos curve. off, SC = σ + δ (1 exp( )) (2) τ Whereσ, δ are he ho and cold sar-up coss respecvely, τ s he un coolng me consan and off, s he me for whch un had been off. he shu down cos (SH ) of he uns have also been consdered. he oher consrans n he model are ramp up of uns, f uns remans n operaon for wo successve hours (2) and ramp down rae lms (21), un s up spnnng reserve conrbuon (24) and un s down spnnng reserve conrbuon (25). Anoher componen ha can play mporan role n elecrcy marke s emsson. he emsson generaon by he hermal uns n generang he requred power s gven by he quadrac funcon gven below. Deparmen of Elecrcal Engneerng, Unv. College of Engg., Osmana Unversy, Hyderabad, A.P, IDIA.

3 16h AIOAL POWER SYSEMS COFERECE, 15h-17h DECEMBER, EmC α + β * P + γ P, (3) =,, * B. Wnd Power scenaros and Elecrcy Prces he wnd power generaors requre no fuel hence, he operaonal cos of wnd uns has been assumed o be zero. he wnd power conrbuon n o he sysem depends upon he predcon of wnd speed. here are dfferen forecasng approaches avalable [17] [18].Sascs and me seres analyss gves good predcon for shor-erm forecasng. umercal weaher predcon echnque can be combned wh neural nework whch uses hsorcal daa as varable. In hs model neural nework oolbox has been used o generae wnd power scenaros combned wh WP daa. o sudy he effec of wnd power varably dfferen scenaros were appled o he model. he sx scenaros generaed are shown n fg.1 below WP1 WP3 WP4 WP5 WP6 WP7 WP me[hrs] Fg1.Wnd power scenaro generaed by neural nework he oupu of he wnd urbne can be obaned by WECS for dfferen speed of he wnd. he wnd energy converson sysem (WECS) oupu can be characerzed as a random varable hrough a ransformaon from wnd speed o he oupu power. he generaon of all he uns of a wnd farm s consdered as sngle eny. he wnd power curve consrans are expressed as follows. Pwk, =, for V, Vc and V, fvo (4) ( V, Vc ) Pwk, = Wr forv, Vc and V, Vr ( Vr V, ) Pwk, = Wr, for V, Vr and V, Vo (6) he wnd curve reflecs ha 1) here s no wnd power producon up o cu-n speed (4); 2) a lnear power oupu relaonshp beween cu-n and raed wnd speed (6); 3) a consan raed oupu beween he raed wnd speed and cuou wnd speed (5).he power oupu wh wnd speed greaer han cu-ou wnd speed s zero. he WECS power oupu s a mxed random varable beween wo dscree values as he raed value and zero value. hs can be explaned from he oupu of equaons (4)-(6). One such scenaro has been generaed (WP2) n fg.1 and appled o he model o nvesgae he effec on cos, reserve and emsson. hough (5) here are many dfferen approaches such as Markov model ec. for analyzng and forecasng elecrcy prces. In hs sudy he approach used n [1] for prce deermnaon has been appled. Fg.2 (a) gves prce varaon for he operang horzon of 24 Hrs. C. Pumped- Sorage Un Operaon he pumped sorage uns play an mporan role o caer o wnd power uncerany and helps n secure, relable and profable operaon of he power sysem. he plans conss of a reservor where he waer s lfed from anoher source (rver, lake and oher reservor ec.).a reversble pumpurbne helps n sorng he waerng durng off peak hours so ha can be sold n he marke durng peak hours. he varables assocaed o he pumped-sorage plan are expressed n erms of energy. hus, n each operang nerval, he sae of he reservor wll be deermned on he bass of he energy sored n hem a he end of he perod. he volume capacy of he reservor wll be expressed as maxmum and mnmum energy level ha can be sored n he reservor. he mulple pumped-sorage plans can be consdered however; n hs model s only one pumped sorage plan ha has been aken for sudy. he daly operaon of pumped sorage s modeled as used n [1]. PL + = PL + M * p * 1 (7) 1 h mn, Mn, max, h * PL Mn, 1 1 max, Mn, PL PL max, PL M (8) 1 (9) (1) PL ) = o ( PL (11) PL = ( ) PL (12) A he begnnng of he (+1) nerval, he avalable energy n he reservor s he nal value n he () h nerval plus he energy pumped by he pumped un, mnus he amoun of energy suppled o he grd. he reservor level s gven by (7), whch clearly depends on he effcency of un as moorng or generang operaon. Equaons (8) and (9) force he pumped sorage uns o abde he lms durng her operaon as generaor or as moor for pumpng waer o he upper reservor. he reservors maxmum and mnmum sorage capacy lm s defned usng (1). he nal level and fnal levels of a reservor s kep same eher maxmum or mnmum n hs model as expressed n (11) (12). he consrans of he pumped sorage un are ncluded n he model o seek he bes generaon paern for convenonal as well as pumped sorage un durng wnd power volales. he lower generaon can be compensaed by he spnnng reserves; however, whou pumped sorage uns hgher wnd power has o be curaled as can lead o congeson problem n he sysem. Wh pumped sorage uns he excess wnd power can be used for sorage of Deparmen of Elecrcal Engneerng, Unv. College of Engg., Osmana Unversy, Hyderabad, A.P, IDIA.

4 16h AIOAL POWER SYSEMS COFERECE, 15h-17h DECEMBER, Sr. o PLmax PLmn Max [MW] ABLE 1 PUMPED SORAGE UI DAA. 1 Max [MW] PL o % PL L h p waer by usng as pump and here by helpng n ulzaon of wnd power o maxmze he prof. III. MODEL FORMULAIO he overall objecve s o maxmze he oal revenue earned by sellng he elecrcy n he marke mnus he operang and manenance cos of he uns. he objecve funcon for he problem can be formulaed as Max (Pr ce * ( P + Pw + 1 ) Cos ) (13) he oal cos of operaon s comprsed of fuel cos, sar up cos and shu down cos. Cos U, 1 = (1 U. [ OC( P ) * U ) * SH,, ], + U, (1 U, 1, ) * SC, + (14) he funcon s subjeced o a se of consrans as gven below: he sysem hourly power balance. he oal power generaon mus be equal o load n each me seps., * U, + Pw + 1 P = he sysem reserve requremen should be me. D (15) Pmax. * U, + Pw + 1 D + Re s (16) he power generaon by hermal uns should be whn maxmum and mnmum lm. P mn P, P max (17) he sysem up-spnnng reserve requremens U, * US, SR+ r%* Pw, (18) Sysem down spnnng requremen U, * DS, r % * Pw,, (19) Rampng up consrans of hermal un P, P, 1 UR, (2) Rampng down consrans of hermal un P, P, 1 DR, (21) hermal un s maxmum up/down reserve conrbuon consrans US max = d%*p max, (22), DS max = d%*p max, (23), hermal uns up/down spnnng reserve conrbuon consrans US = mn (USmax,(Pmax P ), (24),,, DS, = (DS max,,(p, P mn )), mn (25) he oher consrans n he model are ncluded from wnd uns (4)-(6) and pumped sorage uns (7)-(12). he dspach of he uns has o be done consderng demand, elecrcy prces and spnnng reserve requremen a dfferen me of operang nerval. he spnnng reserves have been calculaed by consderng wnd power generaon as well as demand a ha parcular nerval of me. he ceran percenage of he wnd or load demand has been fxed for he allocaon of reserve arge. he maxmum of hese wo has been aken as spnnng reserve value n he smulaon sudes. he mxed neger non lnear programmng has been appled wh COOP solver n GAMS [15] along wh MALAB o mplemen he model. III. ES CASE & RESULS he model has been esed on IEEE 3 bus sysem. he dea s o sudy s operaon when combned wh pumped sorage uns and he wnd power uns. Snce wnd power s varable n naure so pumped sorage un has been used o compensae hose varaons. However because of unceranes of wnd power generaon spnnng reserve has been kep a fracon of wnd power (r=2%) generaon a dfferen me nerval of operang horzon. In addon a mnmum value of hermal un generaon has also been consdered (SR). he maxmum up/down spnnng reserve conrbuons from a sngle hermal uns has been aken (d=1%). he wnd generaor can provde any reserve, however pumped sorage un can ac as reserve n he absence of wnd power and hereby avods he sarng of addonal hermal uns. he rampng rae boh up and down of he hermal uns are also mporan, as major flucuaon n wnd and n load should be accommodaed by he rampng capably of hermal uns. In hs model he up and down ramp raes have been kep 1% of he generaon n prevous nerval. A. Case Sudy he daa of IEEE-3 bus sysem has been used for he case sudy. he sysem consss of sx hermal uns and he daa s gven n [1]. he pumped sorage generaon facly as gven n able 1 s used wh hermal spnnng reserve of 1 MW (SR). I s assumed ha he reservor sar wh empy and wll no keep sorage a he end of he 24 hr operang me horzon. However opmum level of reservor level can also be obaned a he end of 24 Hr operang me. I akes care of he load and wnd power varaons by suably decdng he operaon of pumped sorage uns n generaon and pump mode and hus, lowerng he peak load demand. he smulaon sudy shows ha he waer reservor level rses durng low prce perod. he PS un pump waer durng low prce perod (1-4 & 1-15 Hrs) and generae power when prce also s hgh (5-9 & 15-2 Hrs) Fg2 (a) & (d). he reserve Deparmen of Elecrcal Engneerng, Unv. College of Engg., Osmana Unversy, Hyderabad, A.P, IDIA.

5 16h AIOAL POWER SYSEMS COFERECE, 15h-17h DECEMBER, Prce & Reservor Level Reserve values[mw] 1 5 (a) m e[ H rs ] (c) Resevor Level Prce n $ res1 Res me [Hrs] PS operaon w.r. Prce varaon Wnd Power & Reserve[MW] (b) m e[ H rs ] (d) Res Pw Pump PGen Prce m e[hrs] Fg.2. PS un operaon wh Prce varaon and reserve requred. requred for he sysem s calculaed as dscussed earler where amoun of wnd power and he demand a ha me s aken for he reserve requremen calculaon Fg.2(b) & (c). W and PS Powers [MW] Fg me[hrs] Pump Prce Pw W and W+PS[MW] PS un res o follow he paern of wnd power generaon Fg.3. Anoher mporan advanage wh he use of renewable n he generaon mx s reducon n emsson As he concep of carbon radng has come up GECOS ry o Fg me[hrs] Prce W +PS W 5 Fg.5 Ems wh PS +W Ems whou PS+W Ems whou W x Fg.6 WO PS PS 3 PS 2 Emsson n lb/hr 4 3 Emsson lb/day me[hrs] Wnd Pow er[mw] Analyzng wnd and pumped sorage un operaon durng volale prce and wnd power operaon can be seen ha Wnd and PS combnaon res o maxmze generaon durng hgh prce condon (4-1 Hrs & 16-2Hrs) and reduces durng low prce perod Fg.4. By addng wnd and PS un ogeher n generaon mx he resuls show ha maxmze prof hrough carbon radng or by avodng ax on emsson generaon above a lm. hus can help earn huge revenue by nroducng cleaner sources of energy. Fg.5 shows he effec on emsson. he emsson s reduced hroughou he operang me horzon when boh Wnd and PS uns are added. However when Deparmen of Elecrcal Engneerng, Unv. College of Engg., Osmana Unversy, Hyderabad, A.P, IDIA.

6 16h AIOAL POWER SYSEMS COFERECE, 15h-17h DECEMBER, x Fg.7 WP1 WP2 daa3 6.5 x 1 4 Fg.8 WP1 WP2 WP3 Prof n $ Emsson lb/day PS n MW PS pow er n MW % Change n Prof Fg.9 Emsson n lb/day 3.9 x 14 Fg.1 Em w h reduced load and carbon ax WP1 WP WP [MW] PS n MW load and prces are hgher and avalably of wnd power s low here can be ncrease n generaon and hus resulng n hgh emsson (18-2) Hrs Fg.5. Wh consan wnd power hroughou he operang me nerval he varaon n emsson has been shown n Fg.6 for dfferen sze of PS un. he resul shows ha PS un decreases he emsson by approxmaely by.1 Percen. B. Effec of Sze, Load, Ramp Rae on Prof and Emsson he prof and emsson vary que sgnfcanly when wnd power s used alone wh hermal uns due o mbalances caused by wnd power uncerany. PS uns make a dfference when used wh hs combnaon. o fnd ou he mpac on hese parameers dfferen wnd power scenaros along wh dfferen szes of he PS un were used n he model. he sudy reveals ha as he sze of PS un approaches o he wnd power un he prof remans consan Fg.7. he emsson values were also obaned Fg.8. he rse n prof earned wh he ncrease n he sze of PS un and wnd power s hgh nally and bu deceases as he sze of PS un becomes nearly equal o wnd power un Fg 9. hus helps Gencos o decde abou he sze of renewable o be negraed wh a parcular sysem. he sudy s carred ou for by reducng he load (95 %) and hen ncreasng he ramp rae lms of he hermal uns. I was found ha o maxmze he prof wh emsson ax /resrcon above a lm, he reducon n load s more useful as compared o nroducon of renewable Fg.1.I concludes ha demand sde managemen can be very benefcal under hese condons. Wh ncrease n ramp rae lms he emsson and he prof earned don change que sgnfcanly and however can mpac he opmum sze of he renewable. able 2 below presens deals abou he prof earned by nroducng renewable n o he generaon mx. he prof wh boh PS and wnd power used s que sgnfcan.e. 386 $/day as compared o &/day whou PS un. I s because PS un compensae he varaon of wnd power and reduces he hermal uns cos whch oherwse would be suppled by convenonal uns. ABLE 2. PROFI OBAIED FROM SYSEM OPERAIO Prof Earned n Dollars Decrease n Rev Combned Operaon Whou PS $/day Whou PS & WP $/day COCLUSIO Renewable energy sources are an negral par of generaon mx nowadays. he opmum value of renewable beng negraed o he power sysem s essenal o deermne o maxmze revenue, opmze ulzaon of energy resources parcularly when sgnfcan wnd power s beng negraed. he PS uns can be que useful for hs ype of hybrd sysem. hs paper helps generaon companes o prepare he schedule of operaon for generang uns along wh he amoun of renewable energy sources whch can be negraed effecvely. he sysem has been esed for varous condons lke, prce varaons n elecrcy marke, load changes, wnd varaons and ramp rae changes. he prces of elecrcy, sze of renewable and ax on Deparmen of Elecrcal Engneerng, Unv. College of Engg., Osmana Unversy, Hyderabad, A.P, IDIA.

7 16h AIOAL POWER SYSEMS COFERECE, 15h-17h DECEMBER, carbon emsson have sgnfcan effec on he operaon of he generang uns n a hybrd sysem. However he ssues lke demand sde managemen can also play a val role whch needs o be nvesgaed on such sysem. REFERECES [1] E.D. Casronuovo, and J.A.P. Lopes, On he opmzaon of he Daly Operaon of a Wnd-Hydro power Plan, IEEE ransacon on Power Sysems, Vol.19 o.3, pp , 24. [2] E.D. Casronuovo, and J.A.P. Lopes, Opmal operaon and hydro sorage szng of a Wnd-Hydro power Plan, Elecrcal Power & Energy Sysems, Vol.26, pp , 24. [3] V.S.Pappala, I.Erlch, and S..Sngh, Un Commmen under Wnd Power and Demand Unceranes, IEEE GM 28. [4] X.Guan, P.B.Luh, and P. Rogan, Opmzaon-Based Schedulng of Hydrohermal Power sysems wh Pumped Sorage Uns, IEEE ransacon on Power Sysems, Vol.9 o.2, pp , [5] B.C.Ummels, e.al., Impacs of Wnd Power on hermal generaon Un Commmen and dspach, IEEE ransacon on Energy Converson, Vol.22 o.1, pp.44-51, 29. [6] J.Hezer, D.C.Yu, and K.Bhaara, An Economc Dspach Model Incorporang Wnd Power, IEEE ransacon on Energy Converson, Vol.23 o.2, pp , 28. [7] C.L.Chen, Smulaed-annealng-based opmal Wnd-hermal coordnaon schedulng, IE Gen.ransm.Dsrb. Vol.1 o.3, pp , 27. [8] Wang, J., Shahdehpour, M. and L, Z. (28), Secury-Consraned Un Commmen wh Volale Wnd power Generaon, IEEE ransacon on Power Sysems, Vol.23 o.3, pp [9] A.. Al-Awam, E. Soromme, and, M.A. El-Sharkaw, Opmzng Economc/Envronmenal Dspach wh Wnd and hermal Uns, n Proceedngs of IEEE Conference 29, pp.1-6,29. [1] I.J.Raglend, and.p.padhy, Soluons o Praccal Un Commmen problems wh Operaonal, Power Flow and Envronmenal Consrans, IEEE conference (26), pp.1-8, 26. [11] E. Denny, and, M. O Malley, Wnd Generaon, Power Sysem Operaon, and Emsson Reducon, IEEE ransacon on Power Sysems, Vol.21 o.1, pp , 26. [12] P.A. Ruz, R.C. Phl Brck, E. Zak, K.W. Cheung, and P.W. Sauer, Uncerany Managemen n he Un Commmen Problem, IEEE ransacon on Power Sysems, Vol.24 o.2, pp , 29. [13] J.G. Gonzalez, R.M.R. Muela, L.M.Sanos, and A.M. Gonzalez, Sochasc Jon Opmzaon of Wnd generaon and Pumped Sorage Uns n an Elecrcy Marke, IEEE ransacon on Power Sysems, Vol.23 o.2, pp , 28. [14] A. uohy,p. Mebom, E. Denny, and M. O Malley, Un commmen for Sysems wh Sgnfcan Wnd Peneraon, IEEE ransacon on Power Sysems, Vol.24 o.2, pp ,29. [15] A. Brooke, D. Kendrck, A. Meeraus, R.Raman, and R. E. Rosenhal, GAMS: a User s Gude. Washngon DC: GAMS Developmen Corporaon, 1998 [16] F. L, and B. Kur, Generaon Schedulng n a sysem wh Wnd Power, n Proceedngs of IEEE/Power Eng.Soc.ransmsson and Dsrbuon Conference Exhbon: Asa Pacfc, pp.1-6, 25. [17] I. Sánchez, Shor-erm predcon of wnd energy producon, In. J. Forecas., Vol. 22, pp , 26. [18] S. L, D. C. Wunsch, E. A. O Har, and M. G. Gesselmann, Usng neural neworks o esmae wnd urbne power generaon, IEEE rans. Energy Converson, vol. 16, pp , Sep. 21. Deparmen of Elecrcal Engneerng, Unv. College of Engg., Osmana Unversy, Hyderabad, A.P, IDIA.