Scrap tires are used as fuel because of their high heating value. Using scrap tires is not recycling, but is considered a beneficial use — it is better to recover the energy from a tire rather than landfill it. Tires can be used as fuel either in shredded form – known as tire-derived fuel (TDF) — or whole, depending on the type of combustion device. Scrap tires are typically used as a supplement to traditional fuels such as coal, petroleum coke, or wood.