What fuel should I use for my flamethrower turrets?

Version 0.13 adds flamethrower turrets to the game. They can be operated with crude oil, heavy oil or light oil. Does the choice of oil have any impact on their performance? Also, which one is the more economical choice regarding crude oil consumption (heavy and light oil are made from crude oil and light oil can be made from heavy oil)?

Solution 1:

Does the choice of oil have any impact on turret performance?

Yes. Heavy Oil gives 5% damage bonus, and Light Oil gives 10% bonus.
 

Which one is the more economical choice regarding crude oil consumption?

As Oil Processing produces large amounts of Petroleum (at least 40% of output), which is not useable in flamethrower turrets, and rate of fuel consumption does not change with fuel type, crude oil will be most economical choice.

What fuel should I use?

If you are interested in most economic choice, Crude Oil is the fuel of choice. If you want most DPS from your turret setup, use Light Oil. In most practical setups, there would be noneven ratio of production/consumption of different oil products, so you are probably want to use what you have in excess.

Solution 2:

What is the most cost effective fuel?

When trying to find the most economical fuel it is best to calculate how much it costs to convert one of the fuels to another.

The basic recipes as of v1.1.36:

Advanced Oil Processing:

100 CO -> 25 HO + 45 LO (+ ...)

Heavy Oil Cracking to Light Oil:

40 HO -> 30 LO

When using 3 * Tier 3 Productivity Modules the productivity rises to 130%, which means that we should multiply the outputs with 1.3.

So when put into one equation:

100 CO -> (25 * 0.75 * 1.3 + 45) * 1.3 LO
100 CO -> 90.1875 LO

That means that crude oil is the most economical fuel of them all. If you want the most DMP though, you should use light oil to get an extra 10% damage boost.