Indlela izinhlelo zokusatshalaliswa kwamandla okushisa komhlaba ezisebenza ngayo
Amandla angaphansi komhlaba ayindlela yamandla avuselelekayo esebenzisa ukushisa kwemvelo okuvela ngaphakathi komhlaba. Abantu abaningi bayazi amandla angaphansi komhlaba ngokuthi "ugesi ovela ekushiseni komhlaba," kodwa ngemuva kwawo kulele uchungechunge olude lwezinqubo zobuchwepheshe—kusukela ekuhloleni nasekukhiqizeni kuya ekuguqulweni kube ugesi noma ukushisa, futhi ekugcineni, ukusatshalaliswa kuya kubasebenzisi. Lesi sihloko sixoxa ngendlela izinhlelo zokusabalalisa amandla angaphansi komhlaba ezisebenza ngayo: indlela amandla avela emachibini angaphansi komhlaba afinyelela ngayo emakhaya, ezimbonini, nasezindaweni zomphakathi ngokuphepha, ngokuzinzile nangokuphumelelayo.
1. Kusukela ekushiseni komhlaba kuya emandleni asebenzisekayo
Ukushisa kwe-geothermal kugcinwa ezindaweni zokugcina amanzi ashisayo, okuyizindawo zamadwala anezimbobo noma aqhekekile aqukethe uketshezi (amanzi ashisayo kanye/noma umusi) emazingeni okushisa aphezulu. Lawa machibi ngokuvamile ajula ngamamitha angamakhulu kuya kwayizinkulungwane. Ukuze angene kula machibi, izinkampani ze-geothermal zimba ukuze zilethe uketshezi olushisayo phezulu ngemithombo yokukhiqiza.
Kodwa-ke, kubalulekile ukuqonda ukuthi "ukusatshalaliswa" kwamandla okushisa komhlaba akusho ngaso sonke isikhathi ukuletha umusi noma amanzi ashisayo ngqo emakhaya. Emazweni amaningi, kufaka phakathi i-Indonesia, ukusetshenziswa okuvame kakhulu ukukhiqizwa kukagesi ezitshalweni zamandla okushisa komhlaba (i-PLTP). Uma ugesi usukhiqizwa, usatshalaliswa ngohlelo lukagesi lukazwelonke (inethiwekhi yokudlulisa nokusabalalisa). Kwezinye izifunda (isibonelo, eYurophu noma eNyakatho Melika), amandla okushisa komhlaba nawo asetshenziswa njengokushisa okuqondile ngamanethiwekhi okushisa wesifunda, lapho amanzi ashisayo ethunyelwa kumakhasimende ngamapayipi afakwe ugesi.
Ngakho-ke, uhlelo lokusatshalaliswa kwamandla okushisa komhlaba lungahlukaniswa ngemigqa emibili eyinhloko:
1) Ukusatshalaliswa kukagesi (okuvame kakhulu): ugesi oshisayo → ugesi ezitshalweni zamandla okushisa → inethiwekhi yokudlulisa → inethiwekhi yokusabalalisa → amakhasimende.
2) Ukusatshalaliswa kokushisa (ukusetshenziswa okuqondile): i-geothermal → i-heat exchanger → inethiwekhi yamapayipi okushisa → ikhasimende (indlu/isakhiwo/imboni).
2. Izingxenye ezibalulekile ku-geothermal supply chain
Ukuze kucace, nazi izingxenye ezivame ukuba khona kusukela phezulu kuya phansi:
– Idamu lokushisa: umthombo wokushisa noketshezi.
– Umthombo wokukhiqiza: ugeleza uketshezi olushisayo luye phezulu.
– Uhlelo lokuqoqa: inethiwekhi yamapayipi avela emithonjeni eminingana eya endaweni yokucubungula noma yokukhiqiza.
– Isihlukanisi/ithangi le-flash noma i-heat exchanger: ihlukanisa umusi noma idlulise ukushisa (kuye ngohlobo lobuchwepheshe).
– Ama-turbine nama-generator (okukhiqiza ugesi): aguqula amandla omusi abe amandla omshini bese kuba amandla kagesi.
– I-Condenser kanye nesistimu yokupholisa: ipholisa umusi ovela ku-turbine ukuze ubuye ube ngamanzi.
– Ukufaka umjovo: kubuyisela uketshezi echibini ukuze kugcinwe ukuqhubeka nokucindezela.
– Isiteshi esincane (i-switchyard/isiteshi esincane): sandisa i-voltage kagesi evela kujeneretha ukuze ikwazi ukudluliswa kahle.
– Inethiwekhi yokudlulisa: idlulisela ugesi onamandla aphezulu emabangeni amade.
– Inethiwekhi yokusabalalisa: yehlisa i-voltage bese iyisabalalisa kumakhasimende.
- Izinhlelo zokulawula nokuvikela: i-SCADA, ama-relay okuvikela, ama-circuit breaker, ukulinganisa ikhwalithi yamandla.
3. Indlela ukusatshalaliswa okusebenza ngayo ohlelweni lokukhiqizwa kwamandla (i-PLTP)
a) Ukukhiqizwa nokuqoqwa koketshezi
Uketshezi olushisayo oluvela emithonjeni eminingana yokukhiqiza lugeleza ngepayipi lokuqoqa luye esiteshini sikagesi. Kulesi sigaba, ukwakheka kwepayipi kubalulekile ngoba uketshezi lungabola, luqukathe amaminerali ancibilikile, futhi lube sengcindezini ephezulu kanye nokushisa. Ukuze kuncishiswe ukulahlekelwa ukushisa nokugcina ukuqina kokugeleza, ipayipi laklanywa ngezinto ezifanele kanye nokuvikela, futhi lifakwe ama-valve okuphepha.
b) Ukuguqulwa kokushisa kube ugesi: ubuchwepheshe obuthathu obuvamile
1. Umusi owomile: umusi owomile ujikeleza ngqo i-turbine.
2. Umusi osheshayo: amanzi ashisayo acindezelwe "akhanya" abe umusi lapho umfutho wawo wehliswa kumshini wokuhlukanisa. Umusi uphendula i-turbine, kuyilapho amanzi asele angaphinde afakwe.
3. Umjikelezo we-binary: Ukushisa okuvela kuketshezi lwe-geothermal kudluliselwa kuketshezi olusebenzayo lwesibili (isb., i-isobutane) nge-heat exchanger. Uketshezi lwesibili luyahwamuka bese luphendula i-turbine. Izinzuzo: ukukhishwa okuphansi futhi kufaneleka amazinga okushisa aphakathi nendawo.
Ngemva kokuba i-turbine iphendule ijenereyitha, ugesi ukhiqizwa nge-voltage ephakathi (ngokuvamile kusuka ku-kV ezimbalwa kuya ku-kV emashumini, kuye ngomklamo wesitshalo). Logesi awukasebenzi kahle ekudluliseni ibanga elide, ngakho-ke kudingeka isinyathelo esengeziwe.
c) Indawo yokushintsha kanye ne-transformer: indawo yokuqala yokusabalalisa
Egcekeni lokushintsha, ugesi ovela kujenereyitha udlula ohlelweni lokuvikela nokulinganisa, bese ungena ku-transformer yesinyathelo ukuze ukhushulwe ube yi-voltage ephezulu (isb., 70 kV, 150 kV, 275 kV, noma 500 kV). Isimiso silula: uma i-voltage iphakeme, ugesi uphansi kunamandla afanayo, okuholela ekulahlekelweni okuphansi (I²R) emigqeni yokudlulisela.
d) Ukudlulisa: ukudlulisa amandla avela ezindaweni ezishisayo kuya ezikhungweni zokulayisha
Amasimu amaningi okushisa komhlaba atholakala ezindaweni ezinezintaba ezikude namadolobha, okwenza inethiwekhi yokudlulisela ibe umgogodla wokusabalalisa. Izinselele ezinkulu kulesi sigaba zifaka:
– Ubunzima bokuma komhlaba (ukufinyelela embhoshongweni wokudlulisa, ingozi yokudilika komhlaba).
– Ukuthembeka esimweni sezulu esibi kakhulu.
– Ukuhlanganiswa kokuvikela ukuze ukuphazamiseka endaweni ethile kungacimi indawo ebanzi.
Uhlelo lokudlulisa lusebenza kugridi, luvumela amandla avela ezitshalweni zamandla ezisebenzisa umoya ukuba ageleze aye ezindaweni lapho edingeka khona, hhayi nje esifundeni esiseduze. Izikhungo zokuthumela ziqapha imvamisa, i-voltage, kanye nokugeleza kwamandla ukuze kugcinwe ukuzinza kohlelo.
e) Ukusatshalaliswa: kusukela esiteshini esincane kuya kumakhasimende
Eduze kwezikhungo zokusetshenziswa, ugesi ungena esiteshini esincane esingaphansi kwesiteji. I-voltage yehliswa ibe yizinga lokusabalalisa eliphakathi nendawo (isb., 20 kV noma 13,8 kV) bese isatshalaliswa ngenethiwekhi yokusabalalisa. Eduze kwezindawo zokuhlala, ama-transformer okusabalalisa ayayinciphisa kakhulu ibe yi-voltage ephansi (isb., 220/380 V) emakhaya namabhizinisi amancane, noma agcine izinga eliphakathi nendawo kumakhasimende athile ezimboni.
Ngakho-ke, "ukusatshalaliswa kwamandla okushisa komhlaba" ezinhlelweni zikagesi kufana kakhulu nezinye izitshalo zamandla: uma seziguqulwe zaba ugesi, zilandela ingqalasizinda yegridi. Umehluko usenqubweni ephezulu (ukukhiqizwa kwamandla okushisa komhlaba) kanye nohlobo lwemisebenzi yesitshalo.
4. Ukusatshalaliswa ohlelweni lokusetshenziswa kokushisa olusetshenziswa ngqo
Kwezinye izindawo, amandla okushisa komhlaba asetshenziselwa nokushisa indawo, amanzi ashisayo asekhaya, ukomisa kwezolimo, izindlu zokugcina izithombo, ngisho nezinqubo zezimboni. Uhlelo lumi kanje:
1. Uketshezi olushisayo oluvela emthonjeni wokukhiqiza lugeleza luye endaweni engaphezulu.
2. Ukushisa kudluliselwa nge-heat exchanger emanzini ahlanzekile (i-closed loop) ukuze kulondolozwe ikhwalithi yamanzi ekhasimende futhi kuncishiswe ingozi yokugqwala/ukukala.
3. Amanzi ashisayo ahlanzekile asatshalaliswa ngamapayipi afakwe umswakama kumakhasimende (emakhaya/ezakhiweni/embonini).
4. Ngemva kokusetshenziswa kokushisa, amanzi abuyiselwayo abuyiselwa enkabeni ukuze aphinde afudumale, kuyilapho uketshezi olusetshenziswa ngaphansi komhlaba luvame ukufakwa echibini.
Inzuzo yalolu hlobo ukusetshenziswa kahle kwamandla aphezulu ngoba lugwema ukuguqula ukushisa kube ugesi. Kodwa-ke, ibanga lokusatshalaliswa kwalo livame ukulinganiselwa ngoba izindleko zamapayipi kanye nokulahlekelwa ukushisa kuyanda ngebanga.
5. Uhlelo lokujova: ingxenye ebalulekile yokusimama
Esinye sezimpawu zochungechunge lwamandla okushisa komhlaba ukuba khona kwemithombo yokujova. Ngemva kokuba umusi udlule ku-turbine bese uqina, noma ngemva kokukhishwa kokushisa ku-heat exchanger, uketshezi ngokuvamile lubuyiselwa emhlabathini. Ukujova kuyasiza:
– Gcina ingcindezi yokugcina amanzi ukuze kugcinwe umkhiqizo uzinzile.
- Kunciphisa ukuwohloka komhlaba.
– Nciphisa ukuphuma koketshezi endaweni ezungezile.
Ukubekwa kwemithombo yokujova kumele kuklanywe ngokucophelela ukuze kungapholisi indawo yokukhiqiza ngokushesha kakhulu (ukuqhuma kokushisa) futhi kungabangela ukuphazamiseka kokusebenza.
6. Ukulawulwa kwamandla, ukuvikelwa kanye nekhwalithi
Ukuqinisekisa ukusatshalaliswa okuthembekile, uhlelo lwe-geothermal luhlonyiswe ngalokhu okulandelayo:
– I-SCADA kanye ne-DCS ukuqapha izinga lokushisa, ingcindezi, izinga lokugeleza, ukudlidliza kwe-turbine, kanye nesimo semishini kagesi.
– Ukudluliselwa kokuvikela ukuthola i-short circuit, iphutha lomhlabathi, imvamisa engaphezulu/ngaphansi, i-voltage engaphezulu/ngaphansi.
– Ukulawula okusabelayo (i-capacitor, i-reactor, noma i-generator excitation control) ukuze kugcinwe i-voltage ezinzile.
– Ukulawulwa kokulayisha ukuze umkhiqizo wejeneretha uhambisane nezidingo zegridi.
Izitshalo zamandla ezisebenzisa i-geothermal zivame ukusebenza njengezinto ezikhiqiza i-baseload (steady-state) ngoba amandla e-geothermal atholakala amahora angama-24 ngosuku, izinsuku eziyi-7 ngesonto. Lokhu kunegalelo ekuzinzeni kwesistimu yokusabalalisa, ikakhulukazi uma kuhlanganiswa nezitshalo zamandla ezisebenza ngezikhathi ezithile njengelanga nomoya.
7. Izinselele zokusatshalaliswa kwamandla okushisa komhlaba
Nakuba kuthembekile, kunezinselele ezithile ezivamile:
– Indawo ekude yesitshalo sikagesi yenza ukwakhiwa kokudlulisela kubize kakhulu futhi kudinga izimvume zomhlaba.
– Uketshezi oluphuma ngaphansi komhlaba lungabangela ukugqwala/ubukhulu emapayipini nasemishinini engaphezulu.
– Izingozi ze-geological (isib. umsebenzi we-micro-seismic ohlobene nomjovo) zidinga ukubhekwa nokuphathwa.
– Ukuhlanganiswa kwegridi kudinga izifundo ezinhle zokuzinza kanye nokuhlanganiswa kokuvikela.
Isiphetho
Indlela uhlelo lokusatshalaliswa kwamandla okushisa komhlaba olusebenza ngayo incike endleleni amandla alethwa ngayo. Uma lusetshenziselwa ukukhiqizwa kwamandla, amandla okushisa komhlaba aguqulwa abe ugesi esiteshini samandla okushisa komhlaba (i-PLTP), bese lusatshalaliswa ngama-switchyard, ama-transformer, imigqa yokudlulisa, kanye nemigqa yokusabalalisa kumakhasimende. Uma lusetshenziselwa ukushisa okuqondile, amandla okushisa komhlaba asatshalaliswa ngenethiwekhi yamapayipi avikelwe nge-insulated ane-heat exchangers kanye nokujikeleza okuvaliwe. Kokubili kudinga ukwakheka kobuchwepheshe okunzima, izinhlelo zokulawula nokuvikela ezithembekile, kanye nemikhuba yokujova ukuze kulondolozwe ukusimama kwamachibi. Ngokuphathwa okufanele, amandla okushisa komhlaba angaba umgogodla wokunikezwa kwamandla ahlanzekile okuzinzile nokuthembekile.
Uma ufisa, ngingangeza imifanekiso yeshadi lokugeleza noma ngidale inguqulo yesihloko egxile kakhulu kumongo wase-Indonesia (i-PLTP, inethiwekhi yokudlulisa ye-PLN, kanye nezibonelo zensimu ye-geothermal).
