Sorry, I don't get this. Of course your opposition on something can be based on ideology. That is the case if your opposition is more based on your history and tradition than on current facts.
I personally think that there are enough facts to say that nuclear is not really a great option, but I also think that the Green's opposition is based more on ideology (i.e. because they have been historically against it) than on facts. For me, that is evident when they talk more about nuclear risks in general than about financial considerations.