A method for delivering online orders to customers via a fully unmanned system includes replenishing the pod by using inventory carriers carrying containers via a replenishment hatch, moving an inventory carrier attached to carrier base with a mobile robotic unit in a room of adequate temperature. Additionally, the method includes transferring an inventory carrier at a mini load station and loading the order containers on a delivery carrier. The method further includes transferring a delivery carrier and attaching it to a delivery hatch so that the customer, following authentication, is able to pull the drawers and pick the ordered items.