Home » Heating with pellets » Delivery formats Environmental friendliness of pellets Trees absorb CO2 from the atmosphere as they grow. During combustion of wood, precisely this amount of CO2 is liberated again, so it is no higher than would have occurred had the tree rotted naturally in the forest. Heating with wood pellets is therefore CO2 neutral and makes an important contribution to climate protection. Pellet delivery forms The quality guidelines for transport and storage logistics are defined in ÖNORM M7136.   Pellets are sold by fuel merchants in the following form: In 15 to 30 kg bags for handy filling of the reserve supply container, and 900 kg bigboxes on Euro pallets For automated room and building clearing in loose form by means of bulk road trailer, quantity as required (offered and delivered in kg) Pellets must be transported and stored absolutely dry. They swell up greatly if stored in moist conditions. Therefore, the pellets must be protected against moisture during transport, storage and through to combustion.