NOVELTY - Reducing redox ratio of soda-lime-silica glass comprises: either heating a pool of molten soda-lime-silica glass having iron in a ferrous state and in a ferric state, where the pool of molten glass is heated with an ignited mixture of combustion gas and fuel gas emanating from one or more burners, and flow of the combustion gas exceeds the amount of combustion gas required to ignite the fuel gas such that excess oxygen of the combustion gas oxidizes the iron in the ferrous state to iron in the ferric state to reduce the redox ratio.    USE - The method is useful for reducing redox ratio of soda-lime-silica glass, which is useful in glass sheet and substrate such as photovoltaic cell, solar cell and flat or parabolic mirror for concentrating solar energy, solar power, or diffuser (all claimed).    DETAILED DESCRIPTION - Reducing redox ratio of soda-lime-silica glass comprises: either heating a pool of molten soda-lime-silica glass having iron in a ferrous state and in a ferric state, where the pool of molten glass is heated with an ignited mixture of combustion gas and fuel gas emanating from one or more burners, and flow of the combustion gas exceeds the amount of combustion gas required to ignite the fuel gas such that excess oxygen of the combustion gas oxidizes the iron in the ferrous state to iron in the ferric state to reduce the redox ratio; or heating a pool of molten soda-lime-silica glass in a heating chamber, where the pool of molten glass has iron in a ferrous state and in a ferric state, moving glass batch materials onto the pool of molten glass contained in the heating chamber, where the batch materials have iron in the ferrous state and in the ferric state, melting the glass batch materials as they float on surface of the molten pool of glass, moving oxygen through the pool of molten glass to oxidize the ferrous iron to the ferric iron to reduce the redox ratio, and forming a glass ribbon from the pool of molten glass. INDEPENDENT CLAIMS are included for:    (1) a glass production method, comprising charging raw materials in an upstream part of a furnace, where burners are disposed along the upstream part, obtaining a mass of molten glass, and then leading the mass of molten glass to a zone of the furnace situated further downstream, where at least one burner is disposed in the region of this zone that is fed with an over-stoichiometric quantity of oxidant, and then, forming a glass sheet, the glass sheet has a chemical composition that comprises silicon dioxide (65-75%), aluminum oxide (0-5%), calcium oxide (5-15%), magnesium oxide (0-5%), sodium oxide (10-20%), potassium oxide (0-5%), sulfur trioxide (0.1-0.3%), iron (III) oxide (less than 0.015%) and redox (less than 0.2%);    (2) a glass sheet having the chemical composition that comprises iron (III) oxide (less than 0.025%);    (3) a continuous process for preparing glass comprising successively charging pulverulent batch materials into a furnace, and obtaining a glass bath by melting the pulverulent batch materials, refining the glass bath, then cooling the glass bath, where an oxidizing gas is bubbled within the glass bath after the refining; and    (4) a substrate made of glass, a composition of which is devoid of arsenic oxides, antimony oxides and cerium oxides, where the composition comprises a total iron oxide content of less than or equal to 0.2 wt.% and having a redox of less than or equal to 0.1.