Yeah! I bought the "green" version denatured alcohol for the stoves I made. Bright yellow flames rather than blue (which is kind of cool cause you can see them), but seemed to take a lot longer to get a boil (which is kind of NOT cool (or maybe too cool depending on how you look at it )). Point is: the regular and the green seem to be two different creatures--I'm going back to regular denatured alcohol... you might try regular mineral spirits before you throw in the towel.
I'm all for saving the earth, but in my experience, anything "green"=over-priced & under-performing.