Umnotho wehwanzi

Umnotho wehwanzi usebenzisa iHwanzi ukuze ukhiphe umcalahle emikhakheni yezomnotho okunzima ukuyifakela amazuba,  empeleni, leyo imikhakha "okunzima ukuyiyeka" njengosimende, inqimbi, ezokuthutha ezihamba ibanga elide njll. Ukuze kukhishwe izivuthisi zentshicwa (fossil fuels) futhi kwehliswe ukuguquka kwezulu, ihwanzi likhandwa ngamanzi kusetshenziswa imithombo evuselelekayo efana nesivungu nokukhanya kwelanga, futhi ukuvutha kwayo kuphafuza umusi wamanzi (water vapor) kumoyambulunga.

IHwanzi liyisivuthisi esinesibhekubheku, kuvame ukusetshenziswa njengesivuthisi sezicibazulu, kodwa izinselele ezithile ezimbalwa zivimbela ukukhiqizwa komnotho wehwanzi wezinga elikhulu. Lokhu kuhlanganisa nobunzima bokukhanda izangxoko zesikhathi eside, amathumbu kanye namathuluzi enjini; ukuntuleka kobuchwepheshe benjini obungathengwa nobusebenza ngokuphephile ngehwanzi; ukukhatyazeka ngezokuphepha mayelana nokulumbana okuphezulu kwesivuthisi sehwanzi nesOhwe emoyeni ozungezile; izindleko zokukhiqiza ihwanzi ngenqubo yesicazwamazabu (electrolysis); kanye nokuntuleka kobuchwepheshe bebanesiqa (photochemical) obucazukisa amanzi ngokufanele. IHwanzi lungasabela ngaphakathi kwekhukhu lesivuthisi, elikhiqiza ngokufanele amazuba ngenqubo egusha isiCazwamazuba samanzi. Noma kunjalo umnotho wehwanzi uyathuthuka lusilili njengengxenye encane yomnotho womcalahle ophansi. Nakuba ekuqaleni uhowo lwehwanzi kwakucatshangwa ukuthi alutholakali ngokwemvelo ngobuningi, lokhu sekuveziwe ukuthi akulona iqiniso; isimiso sehwanzi kuyimanje siyasetshenziswa esifundeni saseBourakebougou, eMali, ukukhiqizela amanxuluma azungezile amazuba. Sekuphinde kwavubukulwa ihwanzi elingokwenvelo ezindaweni ezisezwekazini, nezisemanzini eminyakeni yakamuva futhi lokhu kuvule indlela yomkhakha olugwadlu yehwanzi elingokwemvelo, kuseke imizamo yoshintsho lwesidlakalasi. Ngonyaka wezi-2019, cishe zonke  (okungama-95%) izindodla zehwanzi ezingama-70 million ezisetshenziswa minyaka yonke kuhidaniso lwezimboni, ikakhulukazi kwizikhuthazi zokudla komhlaba ezingama-45 ekhulwini, zikhiqizwa ngesiguqula jawani somusi (SMR) eaibuye siphafuzele emoyeni uhowo olungcolile umCalahle ontuhlambili