Business Green: The price of carbon allowances in the EU’s emissions trading scheme (ETS) should be at least £85 a tonne, if they are to encourage firms to switch to low carbon technologies at a pace fast enough to ensure the government meets its emission targets. That is the conclusion of a government-commissioned study into the scheme that will provide fresh ammunition to critics who argue that the government must intervene to push up a carbon price that is currently languishing at around EUR12 per …