Drying, as a process, demands significant input energy due to the high latent heat of water evaporation and the relatively low efficiency of available industrial hot air dryers. Energy consumption in Iranian agriculture exceeds international norms for crop production, surpassing even the calculated estimates for worst-case scenarios. One of the most critical challenges in the production of dried foods is the reduction of energy resource costs for producing high-quality dry products. This study aims to compare four conventional pistachio dryers in Iran: Diesel-fueled Carriage Dryer, Gas-fueled Carriage Dryer, Gas-fueled Wagon Dryer and Diesel-fueled Wagon Dryer, in terms of fuel consumption, energy efficiency and economic factors. The findings indicate that: The fuel consumption volume per unit weight of evaporated water in wagon dryers is approximately 50% less than that in carriage dryers. Gas-fueled wagon dryers have lower overall costs compared to other dryers. Gas-fueled wagon dryers exhibit higher energy efficiency (around 15%) than other dryers.
