Green taxes are the future: so say a large coalition of politicians, economists and environmentalists. Their dual promise of a better environment and extra tax revenues gives these a unique appeal. They seem more popular than other taxes, they help tackle serious global problems and they may even improve the working of the economy.

Countries across Europe, including France, Ireland and Switzerland, are examining the scope for more green taxes. In Britain, the main opposition parties have proposed a “green switch” to environmental taxes. The Liberal Democrats, for instance, called for these as part of “the biggest overhaul to British tax policy in modern times”.