Miniaturization Ability
From the Galactic Civilizations Wiki
Your total miniaturization ability is the amount of extra space (in percentage) that you have available on hulls for placing components. So, a huge hull (which usually has a space of 80) with a miniaturization of +20 would have a space of 96 (80 x 120% = 96).
The following techs provide a bonus to your miniaturization ability: Basic Miniaturization - Enhanced Miniaturization - Advanced Miniaturization - Expert Miniaturization - Ultimate Miniaturization - Supreme Miniaturization
The Yor Collective and the Thalan Empire have racial minaturization bonuses, and the Hyperion Shrinker super project provides a bonus as well.
