Solved a power crisis

[Frightning]

So in my very first factory, I am circa 50 hours in, and I got myself into a serious problem. I was out, busy killing biters with laser turret creep, and didn't notice that my Solid Fuel production wasn't keeping up with factory demand, so I eventually started seeing power trouble (still using mostly Steam at the time). So I went back to base made some more Solid Fuel production, problem persisted. I realized why after checking my Petroleum tank (it was full). Moreover, although I still had quite a lot of Oil stored up, my storage had been being depleted for some time, so I knew that wasn't going to last long term. I needed Solar (and Accumulators), and I needed it yesterday!

So facing a seemingly unavoidable power crisis. I shelved that save and did other things with Factorio. Tonight, I was thinking about how to engineer a fuel system that would allow me to use any of Raw Wood (which if I start in a forest I will have lots of), Coal, or Solid Fuel, and do so in a manner where I can choose what prioritization it has (once I have Energy Distribution Mk1, I have further need for Wood other than to make my Combat Shotgun once I research Military 3, so at that point, the rest of my Raw Wood is disposable). Coal has uses for later-game products and is ultimately finite (though there is LOTS on the map), Solid Fuel is effectively infinite, so long as you get enough Crude Oil deposits to generate enough Crude Oil. So I prefer to rank them (late game) as Raw Wood>Solid Fuel>Coal for use in burner devices. I not only figured out how to do it rather simply with just belts (including splitters and underground belts) and inserters, but then I remembered, my first factory was built where a forest was, and I had stockpiled the excess Raw Wood.

AHA! I could solve my fuel crisis long enough to get Solar power up and running to the point where I could keep up with fuel demand (total average power usage in that base is about 17MW currently, but I had maybe 3MW of Solar at that point, rest was 3 sets of 1-14-10 Steam). I now have 10.5MW of solar with matching accumulators and still have about half of my Raw Wood left. (I achieved easy distribution of Raw Wood for fuel by moving them from their current storage chest to what would normally be my Solid Fuel storage chest, which was integrated into my main fuel line and thus it would start distributing the Raw Wood to my burner devices).

[Thegrover]

I split my coal line to my boilers and put two chests of wood on either side, feeding a 1 belt section which then receives the coalvon either side again. Thus gives wood right of way, and coal is only side fed when there is no wood being loaded.

As soon as I develop bots, I replace the chests with requesters and get wood flown in. You can use a similar trick further up the belts to give solid fuel right of way over coal, so wood goes before SF which goes before coal.

[Frightning]

I split my coal line to my boilers and put two chests of wood on either side, feeding a 1 belt section which then receives the coalvon either side again. Thus gives wood right of way, and coal is only side fed when there is no wood being loaded.

As soon as I develop bots, I replace the chests with requesters and get wood flown in. You can use a similar trick further up the belts to give solid fuel right of way over coal, so wood goes before SF which goes before coal.

That's similar to what I came up with.

[OdinYggd]

My first save also had a tri-fuel scheme for the boilers.

The way I did it was pretty simple too. Just a logi requester for each fuel type, placed in order on a stub of belt that led to the first splitter.

It relied on saturating the belt so that the downstream types could not place material unless the belt was clear, and was as simple as wood fuelblocks coal in that order for the belt to pass by. Feeding from both sides is recommended, but doubles the hardware requirements.

Building this in the 0.13 experimental, I would probably use the stack inserters to make sure the belt stays saturated at all times to avoid unwanted mixing.

Of course it would be plenty possible to use combinators to set the request type of a requester chest based on logi network levels. This would work quite well too.