All units have a certain cost in metal and energy to be built, and that's spent progressively per "tick" (game update, thirty per second)
Energy cost per metal is fixed per tier, only air units cost more e (energy) per metal
A small set of units don't follow this formula:
Standard (Tier 1) solar Collectors cost zero energy to build
Wind Generators cost much less energy per metal than other units in the same tier
Morphing
It's the ability of certain mobile units and structures to change shape and functionality
To start morph click on the button with the destination unit target picture. Morph usually has some tech requirement (researched on the Tech Center), which's shown in red on the unit info bar at the bottom of the UI.
Some structures and units can only be obtained by morphing, others are also available to build directly from outposts and factories
Advanced Structures are 25% more expensive when morphed into
Advanced Mobile Units are 33% more expensive when morphed into
All units remain fully operational during a morph
Morph times get faster after the “Tech Booster” upgrades are researched in the Tech Center
Morphs can be paused, resumed and queued with UI button (shift+q is the shortcut for queue morph)
Morphs can be de-queued by immediately starting their morph (M key shortcut).