Make fuel slots (in a locomotive, car, tank, furnace...) have a filter

[mrvn]

TL;DR

One should be able to select the allowed fuel for each fuel slot in a vehicle.

What ?

Like slots in a cargo wagon can be set to specific items I suggest the fuel slots in locomotives, cars, tanks and any other vehicle entity should have a filter too.

Why ?

I would like to drive my trains with nuclear fuel. But nuclear fuel (moded makes it worse) is hard to produce especially when you first get it. So as backup I would like to use solid fuel, coal or even wood. I would like to set a filter on the first fuel slot to nuclear fuel. Then only nuclear fuel can be put in that slot and the slot is free for whenever nuclear fuel is available. The refuel station can then have one inserter loading nuclear fuel and a stack inserter loading solid fuel / coal /wood. The train will get a mix of fuel and prefer to run on nuclear fuel, if available.

[PTTG]

Seconded, that sounds like a great idea.

[mrvn]

Let's extend this a bit. Why limit it to vehicles. Any fuel slot including furnaces or burner inserter could benefit from this.

In mods like Angels, Pyaddon or now Industrial Revolution you have many cases where a item with fuel value is part of a recipe that you don't want to use as fuel. But it's pure chance which item arrives first and gets put in the fuel slot. Or your fuel runs low and suddenly a different fuel is used.

[ssilk]

I changed the subject a bit according to the former post, which makes a lot of sense to me.

[jodokus31]

+1

You would also be able to limit the amount of (expensive) fuel in a locomotive. Most of the time, i don't need 3 full stacks of fuel (or more for modded locomotives).
Currently, I manually put in some cheap fuel in the last slots to prevent it from filling up with the provided fuel. Works ok, but easy to forget and screw up.

[Vegemeister]

If I wanted my locomotives to run on a lesser fuel if the preferred fuel was unavailable, I would simply use a priority splitter or circuit priority mechanism.

RIP to you guys, but I'm different.

The argument about furnaces getting their fuels and inputs confused is reasonable, though.

[jodokus31]

If I wanted my locomotives to run on a lesser fuel if the preferred fuel was unavailable, I would simply use a priority splitter or circuit priority mechanism.

Works, if you are able to (over)produce desired fuel to fill out train buffers. It's more about finetuning and optimizing the fuel usage in order to profit earlier from the huge speed bonus.

[Factoruser]

I think it would be better to use a smart fueling station setup. I see the trouble more in the improvement of the circuit system; the combinators are extremely useless yet. A simple comparsion "chest A <> chest B" requires 3 combinators for instance and therefore you get rapidly a hell of a cable tangle for most easiest cases.

[foamy]

I mean, you can *sort* of do this with a filter inserter and some combinators for train fuel, but it's ugly. Directly filtering the slots would be very handy.