The production of hydrogen and the fixation of CO2 can be achieved by treatment of flue gases derived from fossil fuel fired power plants via catalytic methane tri-reforming or by coal gasification in the presence of CaO. A two-step process is designed to be carried out in two reactors: a) a catalytic gasifier or steam-reformer, operating exothermally at 900-1000 K, with inputs of the flue gas, a carbonaceous source, steam and air, as well as CaO from the calciner, and outputs of H-2, and of "spent" CaCO3 to the calciner; b) a calciner, operating endothermally at 1100-1300 K, with inputs of spent CaCO3 from the gasifier, make-up fresh CaCO3, and outputs of CO2, as well as of CaO, partly recycled to the gasifier and partly processed in a cement plant. Thermochemical equilibrium calculations along with mass/energy balances indicate that for flue-gas treatment by tri-reforming, CO2 emission avoidance of up to similar to 59% and fossil fuel savings of up to similar to 75% may be attained when concentrated solar energy is supplied as high-temperature process heat for the calcination step, all relative to conventional H-2 production by coal gasification. If instead fossil fuel would be used to drive the calcination step, the CO2 emission avoidance and the fuel savings would be only 20% and 67%, respectively. Estimated annual H-2 production from a coal-fired 500 Mwe burner by the proposed flue-gas treatment using either CH4-tri-reforming or coal gasification would amount to 0.7 x 10(6) or 0.6 x 10(6) metric tons H-2, respectively. Estimated fossil fuel consumption for H-2 production by tri-reforming or coke gasification would be 149 or 143 GJ fuel/ton H-2 (C) 2009 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.