The Shipyard will be used to manage player resources. Through the Shipyard dashboard, you will be able to send resources (Food, Ammo, Gems, Bounty) to different Players or even your own cities.
Troops will be limited to how many resources they can carry by the "Type" of Sol Patrol. Meaning a Sol Patrol Type: Ranger will have a lower capacity of resources that can be traversed across the map when compared to a Type: Chief.
The Shipyard is a defensive building, meaning the higher the level - the more defense strength for your city.