User Tools

Site Tools




Thermodynamics, also called Heat, Overheating or Overloading, is a game mechanic whereby many active modules can be overloaded beyond their normal capacity, providing greater functionality for a short duration at the cost of incremental damage to your modules.

Overheating is used extensively by PvP Pilots, and is a useful button in PvE content such as DED Complexes running or Incursions. It makes almost every ship better, and should be trained on almost all pilots.

What do I need to use Thermodynamics?

Here are the bare essentials required to be able to overload a module:

  • Thermodynamics I
    • Energy Management III
    • Engineering V
    • Science IV

Not too steep, as most characters past 5 million skill-points should already have Science and Engineering trained up. Thermodynamics used to require Energy Management V, which took about two weeks to train. This is no longer the case as of Dominion. Though Energy Management is still a necessary core skill, Thermodynamics is now a trivial skill to train for, and incredibly useful.

The Thermodynamics skill reduces the heat damage modules produce by 5% per level - the bonuses imparted to a module by overloading are a function of the module's stats, and not modified by the Thermodynamics skill. Nevertheless, training this skill to IV is highly recommended if you use heat regularly. No other skills currently affect the use of Thermodynamics, but there are two skills (Nanite Operation and Nanite Interfacing) that improve the functionality of the Nanite Repair Paste that is used to repair damaged modules.

Why should I use Thermodynamics?

  • For a speed boost equivalent to a high-grade Snake set on any ship with an MWD, for 4-5 module cycles (Frigates) to several minutes (Battleships). Be the envy of interceptor pilots everywhere in your T1 Vigil! Catch Vagabond in your Stabber!
  • For extended range on tackling gear, giving a T1 frigate the tackling capabilities of an eve:ships:frigates:interceptors, and allowing any ship with a T2 warp disruptor to laugh off an enemy battleship expecting its heavy neutralizers to break your tackle. Web that pesky Vagabond who thinks it's a good idea to close to 13km for some extra damage.
  • To radically increase the strength of a passive tank, or nearly double the power of an active tank, allowing you to win otherwise impossible fights on a small scale, further frustrate the enemy fleet shooting you, or escape seemingly inescapable situations.
  • To amp up the damage of guns or launchers and climb higher on the killmail than that other asshole who's flying the same ship you are, even when he has better skills. Alternatively, in conjunction with an overheated tank, to kill that other asshole who's flying the same ship you are and thinks he has a snowball's chance in hell of beating you (unless he overloads too, he doesn't). Get that 1300 DPS facerape Torp Raven you've always wanted, today!
  • To increase the drain rate of your energy neutralizers, dropping the activation time of medium neutralizers below that of cap injectors. Yeah, I'm reaching here, but it does make an injected Curse with 4 neutralizers even more terrifying than before.

Or if you fly a Rapier, to do all of the above and become a fast-moving 150km-wide nanoship killzone without equal. Enemy interceptor pilots will speak your name in hushed tones over furtive, ritual hand gestures futilely intended to stave off the sheer terror your presence in local instills.

To see exactly what each module does when overloaded, see the capabilities section below.

How do I use Thermodynamics?

  1. By simply shift-clicking the module you wish to overheat. This enables overloading for that module, but does not activate it.
  2. By clicking the rack overload buttons between the main HUD wheel and the module icons. This will enable all overloadable modules on that rack, but will not activate them.
  3. By using the module and rack overload hotkeys: (Alt/Ctrl) + Shift + F1-F8 by default, for (Med/Low) and High slots (as arranged on the HUD, not the fitting screen).

  • Module overload status is reflected by the green bar above the module's icon. As overloading is a toggle, you de-activate an overheat in the same manner. Remember that module lag affects overload commands too, so as when activating a module normally, don't expect two rapid clicks or keypresses to both activate and then immediately de-activate a module's overload status - it has to first be reflected in the client by the green bar lighting up.

  • Module damage is shown as a red around the module icon, advancing counter-clockwise. You can also see the precise percent of damage a module has taken by hovering over its ring or icon on the HUD. See the section below for ways to mitigate or minimize module heat damage.

The Overloading Interface In Detail

  • Modules can be kept overloaded while inactive, and they will begin overloading when they are activated.
  • If a module is overloaded while active, the overload will begin on the module's next cycle.
  • Inactive modules with overload enabled do not take or produce heat damage until they are actually activated.
  • Modules with a range-bonus overload such as webs and disruptors 'do' have their effective range boosted for their first cycle (as well as on all subsequent cycles) if you overload them while inactive. This is appropriately reflected in their attributes tab if you show info while they're inactive but overload-enabled.
  • Once an overheat is activated on a module, it will continue to overload until de-activated. Make sure you don't leave modules overloaded longer than necessary (such as tackling gear), as you may need to overload them again soon and you don't want them taking too much damage and going offline prematurely.

Nearly all active module types support overloading, with some notable exceptions; sensor boosting/dampening modules, tracking boosting/disrupting modules, Target Painters, Damage Controls and various other non-combat utility modules 'do not' allow overloading. Yes, I too wish to overload my Salvagers and Codebreakers, but alas, it is not to be.

Managing Heat and Overload Damage

Here's the catch. Thermodynamics is certainly worth the ticket price now, but there are still risks to using heat, and it still costs either time or money to repair heat damage to modules. There are just more ways to repair them, and the quantities of damage they do has been rebalanced. In addition, there are now a few ways to reduce the destructive potential of overloading, although they're not always possible (or worthwhile) to implement with every fitting.

Heat Damage

The amount of heat produced is dependent on the individual module's heat damage value (visible in the attributes tab), modified by Thermodynamics skill level. The hull class it's mounted on seems to have no effect, although frigate-class modules produce significant amounts of heat and can burn out entire racks by themselves quite quickly, while battleship-class modules scarcely produce any at all and can be run for extended periods of time with excellent passive effects. For now let's establish some basic facts about heat damage, spreading, and mitigation.

Strategic Cruisers get a bonus which reduces heat damage and substantially extends the amount of heat you can use.

Heat Damage In Detail

  • All modules have 40hp, from micro cap batteries to capital armor repairers, regardless of active/passive status.
  • When modules take 100% damage, they go permanently offline until repaired. Modules are never actually destroyed as a result of overloading, and it is perfectly safe (and more cost-effective!) to overload faction and deadspace modules. Unfortunately, 100% damaged modules cannot be repaired in-flight and require repair at a station.
  • Heat damage is not necessarily taken every cycle – it is a random roll on the combined multiplied values of heat buildup, distance attenuation, and the ratio of offline or empty slots on the ship.
  • However, when damage to any module IS taken, the amount is invariable and based on the inflicting module's heat damage value, reduced directly by your Thermodynamics skill level. Heat damage to any module from a 10mn Microwarpdrive at Thermodynamics I will always be 10.8.
  • Heat damage happens at the end of an overloaded module's cycle.
  • Heat damage only spreads within the rack the module is on. Overloading a midslot module will never damage any high or low slot modules.
  • Heat damage spreads primarily to adjacent modules on the rack, but can even spread to distant modules on the rack. The way the damage chance drops over distance is called attenuation and is based on the number of slots in a rack.
  • When heat spreading from one module causes damage to multiple modules on a rack, each module takes the full damage amount produced by the one that's overloaded. In other words, a 10mn MWD that produces 10.8 heat damage per cycle may do 10.8 damage to itself and 10.8 damage to two other nearby modules on the same cycle due to heat spreading.
  • Offline modules still take heat damage, but otherwise they are treated the same as empty module slots, in that they reduce the chance of taking heat damage for all modules on the ship.
  • Adjacency and heat spreading go by module placement in the rack on the fitting screen, not on the HUD. Heat damage does not appear to wrap around the edges of the rack.
  • Heat buildup persists after docking; your ship cools down normally over time, even when docked. Refitting the overloaded modules doesn't reset the heat status of the ship.

Heat Buildup Over Time

Each rack has a separate heat meter. Heat buildup varies by ship class (larger ships generate less). The heat meters are straight percentile chances: when the meter is at 50%, all modules on that rack have a base 50% chance to take damage. The final chance depends on distance from overloaded modules and the ratio of offline to online modules, but on a typical fit it is a direct indicator of the chance for a single overloaded module to take damage.

Heat dissipates slowly all the time and happens at the same rate regardless of ship (going by the heatDissipationRate variables in the item database, which are all 0.01).

The heat gauges seem to operate on a curve (see buildup math) so it might not be possible to actually reach 100% damage chance.

Heat Damage Mitigation

Module placement on the rack and the adjacency of active/passive module types are important to preventing heat spreading. Because of the way heat spreading works, overheating multiple adjacent modules on a rack simultaneously will accrue damage and destroy modules far more quickly than overheating non-adjacent modules. 'The placement and adjacency of modules in their rack on the fitting screen is what affects heat spreading and heatsinking, not their hotkey slot on the HUD.' Once you have the modules optimally arranged for heat spreading on the fitting screen, you can re-order them on the HUD however you'd like for hotkey purposes and heat distribution will not be negatively affected.

Passive Modules as Damage Buffers

Due to the wording of the devblogs on heat, it was expected that passive modules such as shield extenders and plates would 'absorb' more heat than other modules - however, this is not strictly true. Passive modules appear to take the same amount of heat spreading damage as active modules, but they can still serve the useful purpose of reducing multiplicative heat damage by sandwiching them between two active modules on a rack, preventing two otherwise directly adjacent overheatable modules from damaging each other nearly every cycle. For example, putting an LSE between a web and disruptor will reduce the amount the web and disruptor damage each other when both overheated, since nearer modules take spreading damage more often than distant modules. As the LSE is not overheatable, it cannot damage itself, and will not burn out as quickly as another overheated module in the same position. However, it does not act as a true heatsink the way an offline module does, and will not completely prevent damage from spreading across the rack.

For example, a typical Rapier midslot rack would ideally look something like this:


With the most commonly-overheated modules on the edge of the rack or separated by a passive module. In a rack with 4 out of 6 active, it's necessary to put two actives adjacent; in this case the webs are the best candidates since they'll rarely both need to be overheated simultaneously, or at least not for any significant duration.

Offline Modules as Heat Sinks

The same is true when positioning offline modules or empty slots, although they have the added benefit of reducing the damage chance for all modules on the ship by the ratio of online modules to total slots. To illustrate, say a ship has all its slots fit and overloads the web in its 2nd midslot. Also take for granted that it has 100% midslot heat buildup and the heat attenuation for this ship's midslots is 71% (since it has 5). Its midslot damage chance for every cycle of the web would look like this:

71% 100% 71% 50.4% 35.8%

If, for some reason, half of its total slots were offline or empty, the chances for damage each cycle would be:

35.5% 50% 35.5% 25.2% 17.9%

Leaving that many slots open is obviously impractical, but many ships can leave one or more highslots offline/empty, which grants a small but noticable reduction in average heat damage over time. In addition, empty slots allow you to put some distance between active weapons which reduces stacked damage. For example, a station gank raven might fit its highslots like so:


Which ends up with 17/19 slots filled or a 0.895 multiplier to all damage chances. However, in cases like this where heat is overlapping from many modules, the final damage chances get pretty heavy on statistical math and are hard to easily calculate.

Repairing Heat Damage

Obviously heat damage can be repaired in any station, but previously this was the only way to repair damaged modules which limited the usefulness of heat in deep 0.0 or in fast-moving gangs. With the advent of Nanite Repair Paste, heat damage can now be repaired anywhere so long as you have sufficient nanite paste in your cargohold.

Nanite Repair Paste at a glance

Nanite Repair Paste is in large part why Thermodynamics is so awesome now. If you use Thermodynamics at all, you should definitely keep nanite paste on hand.

  • No additional skills are needed to use repair paste, but there are two skills that improve its efficiency and speed: Nanite Operation and Nanite Interfacing.
  • It's player created through the PI system.
  • It's small (0.01m3), and easy to carry enough for multiple full-rack repairs.
  • It works while cloaked and while running any modules but the ones you're repairing, although you can't overheat while repairing with it.
  • Unfortunately, it cannot repair 100% damaged modules. You'll have to dock for those - so try not to let them burn out.

For detailed information on how to use it and what it works well on, see the Nanite Repair Paste article.

Overloaded Module Capabilities

The effects of overloading varies greatly in power and effect depending on the module in question. As previously mentioned, there's currently no way to alter the strength of the overload bonuses listed in each module's attributes tab. Not all overheatable modules are worthwhile candidates, but most are. Most heat bonuses are not affected by any additional stacking penalties with skills or other modules, in particular bonuses to Duration, Speed, Damage, and Boost/Rep amount. Obviously shield and armor hardeners are still penalized with each other when overheated, but their resist bonus modifies their original base -resist% amount pre-stacking penalty, and does not function as a secondary -resist% bonus to be further penalized beyond the number of hardeners you have. Any exceptions to this rule will be noted in the individual module sections (ECM being a prime example).

This section is incomplete.

Excellent Overloading Candidates

These are the modules that benefit most from Thermodynamics, due either to a significant bonus (microwarpdrives), low heat output (tanking gear), or unmatchable utility (tackling gear). They're listed in order of most heat produced → least heat produced.


  • +50% speed boost
  • 19 damage/cycle for 1mn, 11.4 for 10mn, and 8.2 for 100mn
  • 10-second cycle time (damages '1.9/s', '1.14/s', and '0.82/s' respectively)

Speed boost equal to or better than an HG snake set depending on ship mass. Great for interceptors and frigates when you need the speed to survive or to get a critical warpin, but it won't last long thanks to 1mn MWDs producing the most heat damage of any overloadable module, twice over. For already fast Covert Ops and Recon Ships it can mean near-invincibility when jumping into a gatecamp. For many cruisers and even some battleships, overloading your MWD can mean the difference between getting safely back to the gate and jumping out, or dying horribly 0.5km from jump range; never be afraid to overheat your MWD if you jump into a gatecamp, just don't assume it will give you the speed to burn out of the bubble when you otherwise wouldn't have a chance.


  • +30% range bonus
  • 5 damage per cycle
  • 5-second cycle time ('1 damage/s')

Turns normal webs into 13km webs, great for killing pesky Sabres and overconfident Vagabonds. Faction webs will go out to 18-20km, letting you web something jumping into a gatecamp without needing a Rapier/Huginn/Hyena. ~13 paste to fully repair a T2.

Warp Disruptors

  • +20% range bonus
  • 5 damage per cycle
  • 5-second cycle time ('1 damage/s')

Gives normal WDIIs the same range bonus as a tier-1 interceptor at IV. Perfect for holding a tackle in a really fast ship on initial approach where you might otherwise overshoot out of range, as well as holding a tackle on something with best-named heavy neuts (for 8-10 cycles, at least). ~14 paste to full repair a T2.

Note: Does not apply to Warp Disruption Field Generator (a module that can only be fitted on Heavy Interdictors)

Active Hardeners

  • +20% resist bonus
  • All 0.3 damage per second at varying cycle times and damages per cycle

Gives T2 hardeners resists equivalent to B/C-type deadspace hardeners, rockets deadspace X-types up to -77%. When in doubt, overheat hardeners, because they won't burn out for a long time and won't toast other modules on the rack nearly as quickly as guns and launchers do. Not as cheap to repair as tackling gear, but pretty close (~27 paste for a fully damaged Invuln II).

Armor Reps/Shield Boosters

  • -10% duration bonus
  • +15% rep/boost bonus
  • Shield Boosters - '0.3 damage/s' for small, medium, large, and capital boosters, '0.2 - 0.25/s' for XL boosters.
    • Base Cost: From 44k for a T2 small to 961k for a T2 XL, with faction/deadspace at roughly 1/3 to 1/4 the equivalent-size T2 cost. Capital 51m.
  • Armor Reps - '5.4 damage/cycle' regardless of size class, with varying cycle times. Base damage/s ranges from '0.35' for LARs and CARs to '0.95' for SARs, but these numbers all increase 5% for each level of Repair Systems or Capital Repair Systems up to '1.2 damage/s' for a SAR.
    • Base Cost: Significantly cheaper than shield boosters at 70k - 258k for T2, and 10k-40k for faction. Capital 47m.

At +25% total effectiveness for +10% cap use and a fairly low damage/s, boosters and reps are excellent overheating candidates, just bear in mind that they can break an otherwise cap-stable tank when overloaded. Shield boosters, especially X-Large, have significantly better longevity than armor reps, and the heat damage produced by medium and small armor reps will be on par with MWDs at Repair Systems IV-V. Nanite costs will relatively low for armor reps, but the greatly reduced damage produced by shield boosters nearly compensates for the 3-4x base cost increase. Capital modules are prohibitively expensive to repair, so you'll probably want to restrict overheating them to life or death situations.

Shield Transporters

  • -15% duration bonus
  • 0.9 (Large) to 2.20 (Micro, Capital) damage per cycle
  • 5-second (T1, named) and 4.5-second (T2) cycle times
  • '0.235 damage/s' for Large transporters, '0.305 damage/s' for Medium, '~0.5/s' for Small, Micro, and Capital
  • Base Cost: Ranging from 2-14k for Smalls to 140-575k for Larges. Capital 25m.

Large and medium shield transporters have one of the lowest heat outputs of any overheatable module, making them a relatively good candidate. However, since the only bonus is duration, your boosting capability is still limited by your capacitor. Good for single- or double-transporter Logistics setups that need a bit more transfer in a pinch. Unfortunately, shield transporters are the only item class where named versions have a higher base cost than their T2 equivalents, making them relatively expensive to repair fully (~500k, or about 35 units of paste).


  • 30% bonus to sensor strength
  • 3.4 damage per cycle
  • 10 second cycle time

Overloading ECCM at the beginning of a fight before hostile ECM has been killed or driven off is absolutely recommended. The module takes a few minutes to burn out, so micromanaging its use is not necessary.

Decent Overloading Candidates

Something goes here, eventually. Probably cap injectors, neuts. Guns and launchers go in the above category somewhere, but a few long-range guns and without hull ROF bonuses or short-range guns or launchers with hull ROF bonuses might fall into this category (long-range gun/all launcher overload bonus is also ROF, which also makes them build up heat faster and use more ammo, which sucks). Short range guns get a damage bonus so if you really need that alpha, overloading for a few volleys isn't a bad idea. Heating an afterburner will grant you an additional 50% speed boost, which can bolster a shaky speed tank in a complex or just let you get around faster. Remote armor repairers.

Overheating Math

In a talk at Fanfest 2007, Kristinn “Tuxford” Sigurbergsson disclosed the formulas behind heat. I'm going to try to transcribe the talk as best as I can, but the video is a little fuzzy and the accent makes things difficult.


H = H0(1 - e-tτ)

Setting H0 to 100 would make my graph match his. t is time. τ is a constant based on ship and overloaded modules.

τ = hgm (τ1 + τ2 + … + τn)

Setting the per module τ to 0.025 made my graphs match his. hgm stands for heat generation multiplier, and varies from ship to ship and is visible in Evemon. Lower means less heat buildup.

Ship ClassHeat Generation Multiplier
All frigates 1.0
T1 destroyers 0.85
All cruisers, industrials, and barges 0.75
All battlecruisers 0.65
All battleships 0.5
Carriers 0.4
Dreads, motherships, capital industrials 0.35
Titans 0.25


H = H0(e-tτ)

This time τ is solely based on the ship. Setting τ to be 0.02 makes my graph match his, though he says his line is not necessarily representative of how it works in the game. EVEMon lists heatDissipation, heatDissipationHigh, and heatDissipationLow. This seems to indicate that the dissipation can be different for each rack, though each one on every ship is 0.01 so it's basically moot.


The chance of a module taking damage is based on it distance from the module inflicting the damage.<br/>

reduction = heatAttenuationmoduleDistance

heatAttenuation is a per ship value, though EVEMon lists heatAttenuation and two different heatAttenuationMed variables. It also looks like the heatAttenuation for each rack might be solely determined by the number of slots in the rack. If this is true, then heatAttenuation appears to be for the high slots, and one of the heatAttenuationMeds is for the low slots.

SlotsAttenuationDamage chance multiplier at distance from overheated module
1 0.00 '1' '2' '3' '4' '5' '6' '7'
2 0.25 0.25
3 0.50 0.50 0.25
4 0.63 0.63 0.40 0.25
5 0.71 0.71 0.50 0.36 0.25
6 0.76 0.76 0.58 0.44 0.33 0.25
7 0.79 0.79 0.62 0.49 0.39 0.31 0.24
8 0.82 0.82 0.67 0.55 0.45 0.37 0.30 0.25

Heat sinks

(# of online modules) / (# of module slots)

Offline modules and empty module count as heat sinks. This reduces the chance of damage on all modules on the ship, although offline modules will still take heat damage until they break.

training/game_mechanics/overheating.txt · Last modified: 2019/02/25 20:28 by Fof