Based　on　the　transport　equation　of　the　semiconductor　device　model　for　0.524　eV　GeSn　alloy　and　the　experimental　parameters　of　the　material,　the　thermal-electricity　conversion　performance　governed　by　a　GeSn　diode　has　been　systematically　studied　in　its　normal　and　inverted　structures.　For　the　normal　p(+)/n　(n(+)/p)　structure,　it　is　demonstrated　here　that　an　optimal　base　doping　N　(d(a))　=　3　(7)　x　10(18)　cm(-3)　is　observed,　and　the　superior　p(+)/n　structure　can　achieve　a　higher　performance.　To　reduce　material　consumption,　an　economical　active　layer　can　comprise　a　100　nm-300　nm　emitter　and　a　3　mu　m-6　mu　m　base　to　attain　comparable　performance　to　that　for　the　optimal　configuration.　Our　results　offer　many　useful　guidelines　for　the　fabrication　of　economical　GeSn　thermophotovoltaic　devices.