Factorio Forums

To fill up a certain amount of water with land, it is currently the cheapest to use a filling size (+/-) of 1x1; using bigger sizes (2x2, 3x3, ...) will cost more for the same area.
Furthermore the total cost also depends on the order in which the area is filled. I think a solution where cost is proportional to the filled area would be preferable. Orif anything, bigger sizes should be cheaper (mass discount) if that is the intention.

This is either a bug or you are incorrect. Every tile filled should use 1 landfill, whether it's 2, 4, etc at a time. It might just be confusing because of the game's mechanics with coastlines.

Ok I'll do some proper tests later to either showcase the problem or withdraw my case.

Ok I did some testing, I think the results are pretty conclusive.

I started with 80 landfills:


Now using a 1x1-cursor, I built a square, ended up with 72 landfills left (in another attempt, I ended up with 71 left, I probably built it in a different order):


And now I reloaded, increased the cursor to 3x3 and made a single click. I ended up with 71 landfills while building a smaller square:

did some testing as well as it piqued my curiosity, found that you can get 4 times the fill by going along a straight coast 2 out and every other tile, but it requires you do it a block at a time and any islands you get near with throw it off a bit.

It's a side effect of how shores are treated as land. It's a bit tricky to fix. Though the cost when placed could be adjusted to include the shores/tiles that are automatically landfilled.