Four Seasons Fuel manufacture charcoal retorts and kilns for coal and charcoal production. Charcoal Retorts - of any size to fit your budget. The total output of these Charcoal retorts is around 350 - 400 kg per burn depending on the kind of wood type. Charcoal Kilns - made from mild steel of various thicknesses. Four Seasons Fuel, BBQ Charcoal suppliers in Sussex, UK