@jones @LaChasseuse
What do you mean by "polluting"? Releasing chemicals in the environment in order to produce anything (i.e. transform one energy into another), including production processes to build the necessary technologies? Find me anything that doesn't pollute then. Even the blacksmith or the woodworker are polluting, just to say. If you mean "pollute less" then one should be careful to set the threshold, as many things could be excluded that one would never think of.