Process that can recover the energy of coal seams without the extensive use of traditional mining operations. The primary product brought from underground is hot fully combusted flue gas, 1,100 to 1,800 degrees F (approx. 600 to 1,000 degrees C), whose sensible heat contains most of the heating value of the coal, 5,000 to 13,000 Btu/lb (11.6 to 30.2 MJ/kg). Particularly applicable to coal deposits that are not economically or technically feasible to mine by conventional methods because of seam quality or quantity, depth, dip, strata integrity, overburden thickness, etc.