This mod is to be considered beta. Report any issues you find.
This mod add Lua-driven shield generators for structures and also add internal Turret Shields (which render this mod virtually incompatible with Turret Shields mod and its forks).
Shield generators work similar to ones from Star Wars Galactic Battlegrounds, effectively doubling hitpoints of structures in work range, building up shield hitpoints from its internal battery buffers.
Turret shields can be researched earlier in game and their researcg is separate from Shield (provider) generators, providing every turret with it's own shield.
Turret and Generator shields can be stacked, but Generator shields do not stack on each other.
Research include structures recipes unlock, Shield Generator shield recharge speed, Turret Shields shield recharge speed, Turret Shields battery recharge speed, Turret Shields battery capacity, and an end-game Superconducting Shields research, doubling shield capacity of shields generated by Shield Generators.
Shields have no drain due to performance concerns and being vanilla friendly (vanilla energy shields impose no drain), so if shield got charged it stay charged until taking damage.
This mod has somewhat heavy logic on Lua script side, but it use dirty lists (similar to ones that Factorio use), so UPS should be fine as long as nothing insane happens. Idling turret shields are performance free (script update stays zero), idling shield generators are not performance heavy.