CBC: Ethanol was supposed to be this great fix for the air we breathe. Now it turns out it might be counterproductive, even dirty. At least, that is the view gaining ground in Europe. In principle, biofuels like ethanol were supposed to partially replace conventional fuels, thereby reducing already heavy demand on fossil fuels and offering a non-polluting alternative. As a bonus, the biofuels are made from plants and so demand for the crops of increasingly desperate farmers would …