NOVELTY - Treating a hydrocarbon-containing formation in situ comprises: (1) providing heat from at least one heat source (801) to at least one portion of the formation; (2) allowing heat to transfer from the heat source(s) to a selected section of the formation; (3) controlling the heat so that at least a majority of the section is less than 375degreesC; and (4) producing a mixture from the formation.    USE - Used for treating a hydrocarbon-containing formation to produce a non-condensable hydrocarbons, ammonia, and condensable hydrocarbons. Ammonia is used to produce fertilizer. The heated formation may be used to produce synthesis gas. Synthesis gas is provided to a fuel cell to produce electricity.    ADVANTAGE - The method economically produces high quality hydrocarbons, hydrogen and/or other products from hydrocarbon-containing formations.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for the following:    (A) installing a heater well in a hydrocarbon-containing formation by forming a bore in the ground using a steerable motor and an accelerometer and providing a heating mechanism within the bore such that the heating mechanism can transfer heat to at least a portion of the formation;    (B) a hydrocarbon-containing formation heating system which comprises a heater in an opening in the formation; an oxidizing fluid source and a conduit in the opening;    (C) in situ production of synthesis gas from a hydrocarbon-containing formation by heating a section of the formation to allow synthesis gas generation; providing a synthesis gas-generating fluid (821) to the section and removing synthesis gas (823) from the formation;    (D) forming a spent portion of formation within a hydrocarbon-containing formation which comprises heating a first portion of the formation to pyrolyze hydrocarbons within the first portion and to establish a uniform permeability within the first portion and cooling the first portion; and    (E) sequestering carbon dioxide within a hydrocarbon-containing formation by heating a portion of the formation to increase permeability and form a uniform permeability within the portion; allowing the portion to cool; and storing carbon dioxide within the portion.    DESCRIPTION OF DRAWING(S) - The figure shows a diagram of use of water recovered from pyrolysis fluid production being used to generate synthesis gas.    Heat source (801)    Synthesis gas-generating fluid (821)    Synthesis gas (823)