Does the process of pelleting need steam supply?

Our Biomass Pellet Mill machinery can make wood pellet with or without steam. Our suggestion is to adopt steam supply system when the capacity is more than 1t/h and don't use steam supply system when the capacity is less than 1t/h. Steam supply system will increase investment, on the other side it can increase capacity from 30% to 50% and prolong life of machinery and spare parts.