It's still a bit tricky, but after many iterations, I managed to design a good blueprint. Other wire connections or wire cuts than the ones to power switches are not preserved when blueprinting, so I had to mix poles and place everything perfectly to get it working.
Why perfect? Here's why:
- The ease of laser, without the drain. Power consumption of the drain of triple layer laser down to 2.5% of what it would otherwise be. For layered lasers and a big base, the drain is not only a constant that goes on regardless if you have ongoing attacks or not, but the drain is also actually higher than the energy used by the active turrets while you are under attack! This design reduces drain so much that you can have a constant stream of bugs getting zapped and use less power than a draining design in peaceful mode! Extreme efficiency.
- Blueprintable. Just plonk it down and it works, no manual wire connecting at all. All wires that should connect do. No wire that shouldn't connect do.
- Sections activate independently. You can have a ten thousand tiles long wall and only the chunks that are attacked will be on. You don't get your whole perimeter turned on just because there are random attacks at some places but not others.
- It's 1 chunk long for easy tiling.
- It's only 25 tiles deep from outer stone wall layer to the power poles so it doesn't take up much space and doesn't force bots to fly long distances. A roboport is included in the blueprint within those 25 tiles so repairs and replacements happen quickly.
- Activates quickly so that it has no trouble zapping behemoths.
- Limits the maximum charge in the measuring accumulators so that it deactivates laser immediately and saves you power as soon as the attack stops. It almost looks like the turrets shoot while having the no power icon flashing because it's that quick.
- Can be turned into the always-on mode by circuit network. Just toggle a single constant combinator off or back on again to switch modes. Having power switches toggle constantly might drain your UPS if you have a gigabase, but with a single switch, you can go into draining mode where everything is constant and no updates happen. Not really necessary at any smaller scales though.
- The always-on turrets that are used to monitor for close by natives get fed by the main network also when they turn on all the surrounding turrets so that they can also help with the killing at full effectiveness.
- You can add more layers (up to about 8 total) of lasers without increasing drain at all.
- Beautiful design with turrets in straight lines.
If the monitoring turret is destroyed then the surrounding turrets in that chunk will no longer activate until that turret is replaced by the bots. But even a constant stream of behemoths is unlikely to deal any real damage that risks this. I've seen a spitter hit another turret once, and the lasers survive that while the bugs gets annihilated. Lasers almost never get hurt, though occasionally a single wall piece gets destroyed. It's still so rare it's not worth considering. But it's not really a downside anyways:
- Even if it ever happens you can just toggle the no-drain switch and all your turrets get turned on regardless. (the mod Remote Switches give you constant combinators that you can toggle from anywhere with a GUI)
- And even if you are AFK and can't flip the switch, the biters still get shot by the chunk to the left and right of that single disabled chunk and won't go past your wall to destroy your base. They will just get aggroed by those chunks and all you lose are a handful of lasers at worst.
- And if you have installed mods that make the natives smarter and stronger so that they can deal some damage and avoid turrets, you can just place up to four turrets where the scouting turret stands so there's always one alive to activate the others. This is an extreme measure that no-one against vanilla natives should use since it just increases your drain (to 10%, still quite negligible). Orange in the picture below.
*Edit*: Bonus meme! Corner piece! Always on, but how many corners do you have in your square anyways? Tiles with the bp above and connects the red wire. I'm assuming you place your stone walls touching the chunk border (so not as pictured).
*Edit*: BP updated. Fixed small bug.
*Edit*: Made a BP Book out of the blueprints. Moved some poles a bit north. Added radar (credits below). Added version without radar and place-once circuits for easy placement.
*Edit*: Updated bp book. Straighter power lines. No included radar though. Includes concave corners too now.
*Edit 2020-08-15*: Now the blueprints snap to the absolute chunk grid.
And I also like minimal radar setups to monitor my walls.
There's no space for that in the wall chunk above the medium poles, but if you place the walls against the upper chunk border you can fit it in the same chunk just below the medium poles without unwanted connections.