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With the addition of Flame turrets to the game, something I wondered was "Out of flame and laser turrets, which is more effective and which is more efficient?". So to answer this question, I got a few of the stats from the game (after getting all damage and fire-rate research done).

I'm going to make a few assumptions in this, so when I do, I'll change the font colour like this, or like this if I'm copying a stat, but am not sure that I'm using the stat right


Effectiveness
Firstly, Laser Turrets do 20+24 (44) damage per shot at a rate of 7.8 shots a second: this comes out at 343.2dps.

Next, the turrets target is going to be moving, so I'll only calculate target damage and if the target happens to be in the area of effect (AOE) then I'll ignore that damage.
The Flame Turret shots a flame a second which deals 45+172.8 (217.8) dps, for 8 seconds; which means it'll do 1742.4 damage per flame.

Flame damage's damage over time (DOT) will will either stack, or, will last from the last point of it being applied.
For stacking this means damage will ramp up after the initial engagement until the turret stops firing, where it will decrease, this is calculable by the maximum number of stacks, times the damage applied per stack. stacks last the dot, so 8 seconds and deal 217.8 damage, which means when at peak damage, flame turrets deal 1742.4 dps. However if the DOT just lasts after when it is last applied, then it's a simple 217.8 dps.

This means that either Lasers are more effective then Flame by 57.57...%, or Flame is more effective then Lasers by a whopping 407.69...%.


Efficiency
Once again I'll start with Lasers, Lasers use a base 24kW when not firing and 6.2MW when they are.

Flame on the other hand has no base usage value in the text box and doesn't say it needs to be plugged in when it isn't, so has a base usage of 0kW. Flame turrets also use oil rather then straight electrical charge, so to find out how much energy it uses we'll first need to convert it's oil usage into energy.

This is pretty simple, we have the formulas for how crude oil is converted into heavy, light, and pet oil, and we also have the formulas for how these are converted into solid fuel, which is a simple 25MJ (or 25MW a second). To start off,
- 1 heavy can either be 0.5 fuel, 0.75 light, or 0.5 pet
- 1 light can either be 1 fuel, or 0.66 pet
- 1 pet can be 0.5 fuel
This means that all heavy should be made into light before both light and pet are made into fuel.

Then comparing the 2 crude formulas:
- Basic is 5.25 light and 4 pet (or 7.25 Solid fuel [181.25MJ])
- Adv is 5.25 light and 5.5 pet (or 8 Solid fuel [200MJ])
Adv beats Basic by 1.75 fuel (18.75MJ).

Which means that 1 Crude Oil =20MJ, 1 Heavy Oil =18.75MJ, 1 Light = 25MJ, and 1 Petroleum = 12.5MJ.

Of course we still have to put the Flame Turret's usage (0.12/s of Crude, Heavy, or Light) into this; which is 2.4MJ, 2.25MJ, and 3MJ, respectively.

So, this all equates to Laser using 6.2MJ each second it's firing (with a constant drain when it isn't), and the Flame Turret (at its most efficient) using 2.25MJ each second its firing.
Or in other words the Laser Turret uses 2.75 times more energy then the Flame Turret when firing!


So, What do you think? Maybe you know something I don't, or can fix my assumptions?
I'd Love to hear from you what you think of this, or any improvements on this topic that you can come up with.

- Avaren

PS. I didn't say which was better, because that depends on the game. For this purpose I focused on the common factors.

Laser turret can't hit several biters at once, while flame turret creates area that damage ALL biters entering it.
Flame turret has bigger range.

Your results only valid against single target. Flame turrent efficiency increases with enemy attack size.

If you feed turret with light oil instead of crude, it is another 20% damage bonus.

Flame turret can be dangerous if you setup your defences in forest: only walls and flame turrets have fire resist, other player building will damaged by burning forest. (I lost cople gun turret and underground pipe due forest fires when my turret wall activated)

It will depend heavily on how much effort you want to put into supplying power and resources to your defenses. Electricity is potentially infinite (maps have infinite space and all you need is solar panels and accumulators), but the flame and gun turrets requires resources that are in limited supply. You also have to factor in the logistics of getting the fuel or ammo out to where it is used compared to just stringing up power lines.

How do resistances factor in? If certain aliens were vulnerable to fire then that would be extra reason to use flame turrets. The same would be true if there are vulnerabilities for the other damage types too.

Biters don't have damage resist against laser and they have 50% vunerability to fire. (ingame tooltip states resistance -50%)

Flame turret ammo is infinite. Depleted oil well still produce 0.1 oil/sec. You may want to use it in other production, but it still infinite.

You string fuel same way as power: underground pipes. Flow speed penality may appear at large distances, and you may have to use small pumps, but still it is easier then delivering bullet ammo.

solntcev wrote:Laser turret can't hit several biters at once, while flame turret creates area that damage ALL biters entering it.
Flame turret has bigger range.

Your results only valid against single target. Flame turret efficiency increases with enemy attack size.

If you feed turret with light oil instead of crude, it is another 20% damage bonus.

Flame turret can be dangerous if you setup your defenses in forest: only walls and flame turrets have fire resist, other player building will damaged by burning forest. (I lost couple gun turret and underground pipe due forest fires when my turret wall activated)

Your points are all good, but apart from the light gives a dmg bonus (which I didn't know, also as a point of interest, where did you find out it had the extra damage?) are geared towards factors that I wasn't comparing.

I did say I was ignoring all aoe dmg, which means that the turret would really only be dealing damage to one bitter at a time. If I where to include it's ability to hit multiple targets it's max dps would raise to something like [max targets in aoe Times aoe dmg Plus single target damage].
Range was not a factor I was considering, otherwise arc and min range would also have to be considered.

I didn't consider a lot more and make a more comprehensive post because I was unsure of things (like knowing everything about the flame turret). A post where you compare 2 things will be flawed if the basic logic you build your argument on is flawed, so I decided on doing common factors with a more basic comparison. Once I have a better understanding of flame turrets I may decide to make a post about which is better and try to factor in map settings.

Thanks for your input and the new knowledge!

Light oil I think only has a 10% damage boost.

I think the only weakness in the flame turrets is the targeting system. It makes flame turrets completely useless for small biter attacks. Lasers and bullets are guaranteed to hit their target, while the flame projectile has a travel time. This makes flame turrets excellent for torching spitters, which are going to stop inside the flames and try to shoot at your turrets, but biters will get to the wall before they take any fire damage.

I think flame turrets were designed to be sprinkled throughout your laser defenses as a counter to massive waves of spitters, the kind that are guaranteed to take out a turret or three from a double stack from sheer numbers.

EDIT: This would be excellent for oil bases. In my biggest factory, I have several oil stations that have pumps producing at 0.1/s with piles of speed modules, and apart from production complexes they produce the most pollution, as old mines become solar fields or are removed entirely. As a result, they usually take 3-4 lasers every time the supply train stops by. I've been adding flame turrets in the interests of decreasing my laser consumption, but have not done any experiments yet.

It also seems they occasionally shoot at things that are just out of range, which I discovered when my entire weapons supply tanks ran dry of Light. Make sure there isn't a small worm just out of reach along your walls.

I was wrong about numbers (heavy oil - 5%, light - 10%): Only medium biter has vunerability against fire (strange inconsistency), other biters have no resistance against fire. In my current game I am making solid wall with turrets: one part has 1fire and 2 gun turret repeating pattern, other has only flame turrets in 10 tiles intervals (underground pipe).
Significant drawback of fire turret: it will damage bots, that will try to repair wall, then other bot will try to repair damaged bot and will also burn. Not sure how to deal with it yet.

Looks like that every flame generate pollution, it may attract biters to your defence. And burning forest generate even more pollution and kill trees.

I got 10k burned tree achievement from 2 large forest firest that was started by my turrets.

solntcev wrote: Only medium biter has vunerability against fire (strange inconsistency), other biters have no resistance against fire.

Is this a bug that should be reported? I've noticed this as well, and came to the same conclusion from the resistance formulas that this theoretically means the medium biter is more susceptible to fire. I figure it's either a tooltip display issue or an actual bug. I haven't tried to test whether medium biters really are more susceptible in current gameplay.