Ikiyaga cya Kivu
Ikiyaga cya Kivu ni kimwe mu biyaga bigari bya Afurika. Iherereye ku mupaka uhuza Repubulika Iharanira Demokarasi ya Kongo n'u Rwanda, kandi iri muri Albertine Rift, ishami ry’iburengerazuba rya Rift African Rift. Ikiyaga cya Kivu gisohoka mu ruzi rwa Ruzizi, rutemba rugana mu majyepfo mu kiyaga cya Tanganyika.

Ubumenyi bw'isi 
Ikiyaga cya Kivu gifite uburebure bwa kilometero 26 (26 mi) n'uburebure bwa kilometero 50 (31 mi). Imiterere yayo idasanzwe ituma gupima ubuso bwacyo bugoye; byagereranijwe ko bifite ubuso bungana na km2 2700 (1,040 sq mi), bikaba ikiyaga cya munani muri Afurika. Ubuso bw'ikiyaga bwicaye ku burebure bwa metero 1.460 (hejuru ya 4,790) hejuru y’inyanja. Iki kiyaga gifite amahirwe yo kurwara limnic buri myaka 1000. Ikiyaga gifite ubujyakuzimu bwa metero 475 (metero 1.558) n'uburebure bwa metero 220 (722), kikaba kiyaga ikiyaga cya cumi n'umunani cyimbitse ku isi ku bujyakuzimu, naho icyenda ikaba ikuzimu.

Ibirometero kare 1,370 (529 sq mi) cyangwa 58 ku ijana by'amazi y'ikiyaga biri mu mbibi za DRC.

Uburiri bw'ikiyaga bwicaye ku kibaya gitemba kigenda gitandukana buhoro buhoro, gitera ibikorwa by'ibirunga muri ako gace.

Ikirwa cya cumi kinini ku isi mu kiyaga, Idjwi, kiri mu kiyaga cya Kivu, mu mbibi za Parike y'igihugu ya Virunga. Gutura ku nkombe z'ikiyaga harimo Bukavu, Kabare, Kalehe, Sake na Goma muri Repubulika Iharanira Demokarasi ya Kongo, na Gisenyi, Kibuye, na Cyangugu mu Rwanda.

Ubutabire 
Ikiyaga cya Kivu n'ikiyaga cy'amazi meza kandi, hamwe n'ikiyaga cya Kameruni cya Nyos n'ikiyaga cya Monoun, ni kimwe muri bitatu bizwi ko biturika. Hafi y'ikiyaga, abahanga mu bumenyi bwa geologiya [bagenzuye bakeneye] basanze ibimenyetso byerekana ko abantu benshi barimbutse mu myaka igihumbi, bikaba bishoboka ko byatewe n'ibyabaye. Impamvu y’ikiyaga cyasenyutse mu kiyaga cya Kivu ntikiramenyekana, ariko ibikorwa by’ibirunga n’imihindagurikire y’ikirere byombi bikekwa. Imyuka ya gaze yibiyaga biturika irihariye kuri buri kiyaga. Ku bijyanye n'ikiyaga cya Kivu, kirimo metani (CH4) na dioxyde de carbone (CO2), biturutse ku mikoranire y'amazi yo mu kiyaga n'amasoko ashyushye y'ibirunga.

Ingano ya metani iri munsi yikiyaga ngo ni kilometero kibe 65 (16 cu mi). Niba yatwitse umwaka umwe, byatanga impuzandengo ya gigawatt 100 (130 × 106 hp) mugihe cyose. Ikiyaga kandi gifite kilometero kibe 256 (61 cu mi) ya dioxyde de carbone, iyo irekuwe mugihe cyo guturika, ishobora guhumeka abatuye ikiyaga cyose. Ubushyuhe bwamazi ni 24 ° C (75 ° F), naho pH ni 8,6. Methane ivugwa ko ikorwa no kugabanya mikorobe yo kugabanya ikirunga CO2. Ahazaza hasenyuka na gaze mu mazi maremare y’ikiyaga cya Kivu byavamo amakuba, bigatuma ikiyaga cyanditswe mu mateka cyasenyutse ku biyaga bito cyane bya Nyos na Monoun. Ubuzima bwabantu bagera kuri miriyoni ebyiri batuye mukibaya cyikiyaga bwugarijwe.

Ibice biva mu gace ka Bukavu Bay kiyaga bigaragaza ko hepfo hashyizwemo imyunyu ngugu ya monohydrocalcite idasanzwe ihujwe na diatom, hejuru yubutaka bwa sapropelique irimo pyrite nyinshi. Ibi tubisanga intera eshatu zitandukanye. Ibice bya sapropelique byitwa ko bifitanye isano no gusohora hydrothermal na diatom kumurabyo wagabanije urugero rwa karuboni ya dioxyde de carbone hasi bihagije kugirango igabanye monohydrocalcite.

Abahanga mu bya siyansi bavuga ko imikoranire ihagije y’ibirunga n’amazi yo hepfo y’ikiyaga gifite ingufu nyinshi za gaze byashyushya amazi, bigahatira metani mu mazi, bigatera metani iturika, kandi bigatera kurekura icyarimwe karuboni ya dioxyde. Dioxyde de carbone noneho yahumeka abantu benshi mukibaya cyikiyaga mugihe imyuka iva hejuru yikiyaga. Birashoboka kandi ko ikiyaga gishobora kubyara tsunami yikiyaga mugihe gaze iturika.

Umuyoboro w’ubushakashatsi washyizwe ku kiyaga cya Nyos mu 2001 kugira ngo ukure gaze mu mazi maremare, ariko igisubizo nk'iki ku kiyaga kinini kinini cya Kivu cyaba gihenze cyane. Toni zigera kuri miriyoni 510 (toni 500 × 106 z'uburebure) za dioxyde de carbone mu kiyaga ni munsi ya 2 ku ijana by'amafaranga arekurwa buri mwaka no gutwika amavuta ya fosile. Kubwibyo, inzira yo kuyisohora irashobora kuba ifite amafaranga arenze kubaka no gukoresha sisitemu.

Iki kibazo kijyanye no gukwirakwiza metani ni icya mazuku, ijambo ryigiswahiri "umuyaga mubi" ryo gusohora metani na dioxyde de carbone yica abantu n’inyamaswa, ndetse ishobora no kwica ibimera mugihe cyinshi cyane.

Gukura metani mu kiyaga 

Ikiyaga cya Kivu giherutse kugaragara ko gifite miriyari 55 m3 (tiriyoni 1,9 cu ft) za biyogazi yashonze ku bujyakuzimu bwa metero 300 (1.000 ft). Kugeza mu 2004, gucukura gaze byakozwe ku rugero ruto, gaze yakuweho ikoreshwa mu gukoresha amashyiga mu ruganda rwa Bralirwa i Gisenyi. Ku bijyanye no gukoresha cyane uyu mutungo, guverinoma y'u Rwanda yaganiriye n'amashyaka menshi yo gukora metani iva mu kiyaga.

Mu mwaka wa 2011, ContourGlobal, isosiyete ikora ingufu mu Bwongereza yibanda ku masoko agaragara, yabonye inkunga yo gutangiza umushinga munini wo gucukura metani. Uyu mushinga unyuzwa mu kigo cy’u Rwanda cyitwa KivuWatt, hifashishijwe urubuga rwa barge rwo mu nyanja gukuramo, gutandukanya, no gusukura imyuka yavuye mu buriri bw’ikiyaga mbere yo kuvoma metani isukuye binyuze mu muyoboro w’amazi ugana kuri moteri ya gaze ku nkombe. Icyiciro cya mbere cyumushinga, giha "genseti" eshatu ku nkombe yikiyaga no gutanga MW 26 z'amashanyarazi kuri gride yaho, kuva cyarangiye. Icyiciro gikurikira kigamije kohereza genseti icyenda ziyongera kuri MW 75 kugirango habeho ubushobozi bwa MW 101.

Byongeye kandi, Symbion Power Lake Kivu Limited yahawe amasezerano yo Korohereza no Gutanga Amashanyarazi (PPA) mu 2015, kugirango itange MW 50 z'amashanyarazi ukoresheje metani ya Kivu. Biteganijwe ko umushinga uzatangira kubakwa muri 2019, ingufu za mbere (Icyiciro cya 1 - 14 MW) zizakorwa mu gihembwe cya mbere 2020. Uruganda ruzatangira gukora mu 2021.

Symbion Power yaguze ubundi buryo bwo kongera ingufu za MW 25 kandi kuri ubu barimo kuganira na PPA n’itsinda ry’amashanyarazi mu Rwanda rishobora kubona MW 8 z'amashanyarazi zoherejwe kuri Grid nyuma y'amezi atandatu PPA ishyizweho umukono. Iyi nyungu iri kurubuga rwumwimerere wicyitegererezo uzwi nka KP1.

Usibye gucunga gucukura gaze, KivuWatt izanayobora inganda zitanga amashanyarazi no kugurisha ingufu z'amashanyarazi guverinoma y'u Rwanda hashingiwe ku masezerano y'igihe kirekire yo kugura amashanyarazi (PPA). Ibi bituma KivuWatt igenzura itangwa ryingufu zitangwa kuva aho zivuye kugeza aho zigurishwa muri gride yaho. Gukuramo bivugwa ko bikoresha amafaranga menshi kandi byoroshye kuko iyo amazi akungahaye kuri gaze amaze kuvomwa, imyuka yashonze (cyane cyane dioxyde de carbone, hydrogen sulphide na metani) itangira kubyimba uko umuvuduko wamazi ugabanuka. Biteganijwe ko uyu mushinga uzongerera ingufu u Rwanda ubushobozi bwo gutanga ingufu inshuro zigera kuri 20, kandi bikazafasha u Rwanda kugurisha amashanyarazi mu bihugu bituranye na Afurika. Ikigo cyahawe amasezerano y’umwaka wa 2011 muri Afurika y’amashanyarazi kubera guhanga udushya muri gahunda yo gutera inkunga yakuye ahantu hatandukanye ku mushinga wa KivuWatt. Uruganda rw'amashanyarazi miliyoni 200 rwakoraga kuri MW 26 muri 2016.

Umusozo 
N’ubuwo bikigoye gushyira mu bikorwa kubyaza umusaruro izi mbaraga zihishe mu kiyaga cya Kivu kubera uburyo bw’ubushobozi bw’amafaranga ndetse n’ubumenyi.

U Rwanda rushyize imbaraga mu kubyazamo ibisubizo by’amashanyarazi ku baturage mu cyakabaye ari icyago kuri bo.Ngira ngo urabona ko gaze metane atari atari icyago nk’uko byagaragaraga mbere y’uko habonekamo igisubizo.

Isoko z'inyandiko