Glass is one of the simplest and most efficient materials to recycle.
The raw materials for glass and cheap and plentiful; processing facilities are sparse requiring long distance transport of collected cullet; there is an oversupply throughout Europe and North America causing quantities of glass to be landfilled. Less than one quarter of the energy savings of using cullet over raw materials are attributable to the actual production process in the furnace, with the remaining savings in extraction and transport costs. It possible that transport costs (environmental and economic) have not been saved at all, but simply transferred to local authorities who are collecting the glass on the industry's behalf. And with typical collection costs of over £100 per tonne versus current cullet prices of £20-30, and price cuts looming, these are already loss-making operations.