Uses a big Perspex dome with a long tube built into a slider leading from a side easy insertion level to a point just over cone leading to the base centre. Like a telescope observatory. At base centre in interior an old wood chipper motor/blade or shredder, geared to be connected to a cycle-powered input. You 'load' PEP bottles into the tube. You then slide it upright (using screwed in 330ml bottle handles) to drop into the cone. This action activates the blade, only once the tube is well out of reach.The chipper shreds the bottles into shards and flings them out and up the cone to fill the surrounding space with packed cullet.

Submitted by Peter M