In　coal-fired　power　plants,　steam　is　extracted　from　steam　turbine　to　supply　the　regeneration　heat　for　chemical　absorption　carbon　capture.　This　research　analyses　the　steam　and　heat　consumption　of　a　CO2　capture　system　for　different　extracted　steam,　as　well　as　the　influences　of　different　extracted　steam　on　electricity　production　and　power　plant　electric　efficiency.　Results　show　that　specific　steam　consumption　and　specific　heat　consumption,　which　only　reveal　the　quantity　of　the　steam　consumption,　could　not　be　used　for　evaluating　the　true　energy　savings　of　different　steam　extraction　methods.　Specific　exergy　consumption　of　the　extracted　steam　(SEXCS),　which　focuses　on　both　the　quantity　and　quality　of　energy,　is　proposed　and　used　as　a　main　comprehensive　evaluation　index　in　the　CO2　capture　system.　Compared　with　specific　steam　consumption　and　specific　heat　consumption,　SEXCS　can　better　evaluate　the　true　energy　saving　of　the　different　extracted　steam.　Compared　with　plant　electric　efficiency　and　specific　primary　energy　consumption　for　carbon　avoided　(SPECCA),　SEXCS　is　both　simple　in　calculation　and　easy　in　acquiring　the　required　data.　SEXCS　is　thus　recommended　to　be　used　as　an　important　index　for　selection　of　steam　extraction　schemes　for　CO2　capture　systems.　(c)　2016　Society　of　Chemical　Industry　and　John　Wiley　&　Sons,　Ltd