If you want to purchase a pellet mill one of the biggest issues for many people is the lack of a suitable three phase power supply to run most pellet machines. There is a large selection of small pellet mill machines coming out of china with diesel engines attached. These are basic single cylinder diesel engines used on budget Chinese tractors. While these engines provide sufficient torque, they are not very efficient compared to modern diesel engines. Therefore the costs to run one of these small pellet mill machines can be quite high. If you compare the costs to running on electricity, there is a significant cost difference. However there are some small pellet mill presses such as those from the UK than let you run the mill from a single-phase power supply. However with these products they are only suitable for small productivities per hour, and they are produced for research purposes.