> Why would growing corn for ethanol and burning it in an engine be any climate-friendlier than growing that same corn for food and burning an equivalent amount of gasoline in an engine? The carbon absorbed in the field wouldn’t change; neither would the carbon emitted from the car. If the only difference was that producing ethanol emitted much more carbon than producing gasoline, where were ethanol’s benefits?
Where the carbon comes from matters.
When you burn gasoline all of the carbon emitted is carbon that until we took the petroleum it was in out of the ground had been out of the atmosphere for millions of years.
When using gasoline on an ongoing basis the result is a large net increase in atmosphere carbon from burning the gasoline, plus whatever similarly old carbon is emitted during the processing of the petroleum into gasoline.
When you burn ethanol that was made from corn all of the carbon emitted is carbon that was in the atmosphere until the corn took it out of the atmosphere to use in photosynthesis.
When using ethanol from corn on an ongoing basis there is no increase in atmospheric carbon from burning the ethanol. There is just an increase from whatever old carbon is emitted in the process of growing the corn and turning it into ethanol.
Where the carbon comes from matters.
When you burn gasoline all of the carbon emitted is carbon that until we took the petroleum it was in out of the ground had been out of the atmosphere for millions of years.
When using gasoline on an ongoing basis the result is a large net increase in atmosphere carbon from burning the gasoline, plus whatever similarly old carbon is emitted during the processing of the petroleum into gasoline.
When you burn ethanol that was made from corn all of the carbon emitted is carbon that was in the atmosphere until the corn took it out of the atmosphere to use in photosynthesis.
When using ethanol from corn on an ongoing basis there is no increase in atmospheric carbon from burning the ethanol. There is just an increase from whatever old carbon is emitted in the process of growing the corn and turning it into ethanol.