It is available for free when placed during the Collect to Upgrade! Goal and takes 0 Energy to build. Upgrading and completing this requires players to collect 5 different materials, but only 3 are required per level. Once built to Level 6, it allows an extra 4,250 Population. Collecting from this every 24 hours will give the player 250 Coins.
Removal sends it back to your inventory, though you will have to rebuild it.