When the shield is hit by weapon fire, the HP will drop, but each shield has a recharge rate to counter that to some extent. While the Shield-HP are “loaded” by converting some amount of Pentaxid, the shields themselves of course need some significant amount of power when being activated and run. The shields require a shield generator and pentaxid tank. You will have to make a choice when to activate the shields and when to drop them. This of course also means that you or your opponent cannot add or remove or repair blocks or devices (like turrets) in the middle of a fight, as this this would feel like exploting the polarized hull protection. This means, even if you are inside a base, the shield is not a barrier, but active on ANY exposed block! Because of that, we call them ‘hull polarization shields’, adding a virtual shell with a defined value of Hipoints around your vessel or bases exposed areas.
Please note, that these are not ‘bubble shields’ but are designed as an integrated layer on top of the individual building blocks. Shields are available for all vessels and for bases - in different protection levels.