Inlet air temperature and humidity to the dryer: The tem- perature and humidity of the ambient is location specific. The temperature of the inlet air as the designated heat sink provides essential temperature driving to recovery exhaust heat, which is directly related to the size of the exhaust heat exchanger. The inlet temperature will vary during a day/night and over the production season. Less humidity air is advantageous in terms of dryer capacity, but it also has a lower heat capacity flow rate, which means less recovered heat and steam is needed to raise the temperature of the air to approximately 200 C.