[en] This paper reports the analysis of outcomes for a 3000 MWt HTGR plant, given price and cost assumptions, and determines what level of hydrogen and electricity production would optimize the plant economically and environmentally (carbon reduction). Coupling nuclear power with hydrogen production could fundamentally alter the character of the nuclear industry and nuclear technology's development path. For this to happen, the hydrogen economy will have to be realized, and a new generation of reactors technically suitable to co-production of hydrogen with electric power must be developed and proven. The paper shows that the tradeoff between producing hydrogen through steam methane reformation and producing electricity is disproportionate and would require significant price increases for electricity to change the outcomes. It also found that estimate of shadow values for carbon credits was in the range now under discussion.