NOVELTY - Heat from heat source(s) is provided to at least one portion of a coal formation. The heat is transferred to a selected section of a formation. The heat from the heat source(s) is controlled such that an average temperature within at least a majority of the selected section of the formation is less than 375degreesC, and a mixture is produced from the formation.    USE - For producing synthesis gas, hydrogen which is used for upgrading oil, ammonia (all claimed) which is used for producing urea, carbon material which is used for steel manufacture and hydrocarbons. The synthesis gas is used for producing paraffins which are used for diesel, jet fuel and naphtha products, and for producing methane, methanol and gasoline. The synthesis gas is used as combustion fuel for heating the formation. The synthesis gas is used in energy generation units such as molten carbonate fuel cell, solid oxide fuel cell and other type of fuel cell. The cooled, spent portion of the coal formation is used to store and/or sequester materials such as carbon dioxide.    ADVANTAGE - A mixture of high quality hydrocarbon products, hydrogen and other products, is produced. The hydrocarbons are pyrolyzed within a larger area of portion using fewer heat sources, as spacing between the heat sources is selected to increase the effectiveness of the heat source, thereby economic viability of selected in situ conversion process for hydrocarbon is increased. Uniformity of heat distribution in selected section of the formation is increased. The coal formation is heated economically, using systems having durability. The pressure of hydrogen in produced fluid is controlled, such that large amount of fluids having improved quality is provided. The reducing agent added to formation, reacts with hydrocarbon fragments to form selected products and inhibits production of non-selected products. The porosity of portion(s) of the formation is increased uniformly. The pyrolyzed portion(s) of formation has improved uniform permeability, thereby produces synthesis gas with high recovery efficiency, heating value and desired composition. The formation when cooled, increases strength of rock in the formation and absorptive capacity of the formation. Fluid released to the environment due to the operation of the in situ conversion process, is reduced or eliminated.    DETAILED DESCRIPTION - Heat from heat source(s) is provided to at least one portion of a coal formation. The heat is transferred to a selected section of a formation. The heat from the heat source(s) is controlled such that an average temperature within at least a majority of the selected section of the formation is less than 375degreesC, and a mixture is produced from the formation. The pressure within at least a majority of selected section of the formation is controlled to at least 2.0 bar such that a mixture is produced which contains 0.1-15 weight% of olefins. The heating energy/day provided to coal formation volume is at most Pwr which is given by relation: Pwr = hxVxCvxPB, where h is average heating rate of the formation, PB is formation bulk density, V is volume of formation and Cv is average heat capacity, and the heating rate is less than 10degreesC/day. The heat is transferred such that the selected portion has thermal conductivity of greater than 0.5 W/(m.degreesC). INDEPENDENT CLAIMS are included for the following:    (1) In situ method for heating coal formation;    (2) In situ method of producing hydrogen from coal formation;    (3) Method for forming heater wells in coal formation;    (4) System configured to heat coal formation;    (5) Mixture produced from a portion of coal formation;    (6) In situ production of synthesis gas from coal formation;    (7) Method for forming spent portion of formation within coal formation;    (8) Method for sequestering carbon dioxide within coal formation;    (9) Method for in situ production of energy from coal formation;    (10) Method for producing ammonia using coal formation; and    (11) Method for treating hydrocarbons in at least a portion of coal formation.