At the top of the file a local holds the cost, and ConfigureShard() applies it. Lower the local to make extraction cheaper. Note the threshold logic right below it: if the cost is 0.006 or more, the visual bonus indicator is 0, otherwise 1. 

local store_vesselExpExtractionCost = 0.006666666
-- inside ConfigureShard():
cvars.store_vesselExpExtractionCost = store_vesselExpExtractionCost
if cvars.store_vesselExpExtractionCost >= 0.006 then
  cvars.store_vesselExpExtractionCostVisualBonus = 0
else
  cvars.store_vesselExpExtractionCostVisualBonus = 1
end
Set the local to e.g. 0.001 for cheap extraction (visual bonus flips to 1 automatically).

Comments

5 + 2 =
Solve this simple math problem and enter the result. E.g. for 1+3, enter 4.