Heat pipe

2024-03-10T11:55:54Z

CrusaderDeleters: Adjusted wording for reactor transmitting heat

{{Languages}}
{{:Infobox:Heat pipe}}

The '''heat pipe''' can transport heat over longer distances and connect devices which produce and use heat. Currently this is limited to [[heat exchanger]]s and [[nuclear reactor]]s.

Heat pipes have a heat capacity of 1 MJ/°C. Thus, they can theoretically buffer 500 MJ of heat energy across their working range of 500°C to 1000°C, making them a space-efficient energy store. However, because temperature needs a drop of greater than 1 degree before it will "flow," you can't raise them all the way to 1000°C or drain them all the way to 500°C, so the practical energy capacity will depend on the layout.

As heat pipes rise in temperature, they will give off a very low-distance glow.

== Heat pipe throughput ==

Heat pipes are acting very similarly to fluid [[pipe]]s: they each hold an amount of heat energy and there is a limit to how much energy can go through each of them for a given duration.

For any heat pipe entity with one input connection on one side and one output connection on another, this entity with lower the temperature by <code>1 + (P / 15) °C</code> with P being the power going through this entity expressed in MW.

Since a nuclear power plant can have at most 500°C difference between the hottest (a [[nuclear reactor]]) and coldest (a [[heat exchanger]]) points of the system, that means that we can express the maximum length of a straight line of heat pipe as <code>500 / (1 + P/15)</code>.

For example let's take a single [[nuclear reactor]] outputting 40MW of heat power to a single line of heat pipes. The furthest that line can go is <code>500 / (1 + 40/15)</code> which is around 136 heat pipes long.

A nuclear reactor can also be used to transfer heat in a similar manner as a heat pipe, whether or not it's fueled. In this case, the reactor will drop the temperature by <code>1 + (P / 387) °C</code>, with P again being the power in MW going through the entity. Note that this is an approximation, the actual value measured is supposed to be 200000/517 or about 386.847.

That being said, the nuclear reactor entity is also much bigger, meaning that we must compare it to 5 lines of 5 heat pipes instead of just a single one. The nuclear reactor will thus lower the temperature 5 times less with near-zero power going through it, and nearly 26 times less when approaching infinite power, compared to those lines of heat pipes.

As an example, a single line of 100 nuclear reactors (or 500 tiles) will only lower the temperature by about 360°C while carrying 1GW.

== History ==
{{History|0.17.67|
* Heat pipes (also in reactors and heat exchangers) glow with high temperatures.}}

{{History|0.15.11|
* Changed heat transfer mechanics, prior to this heat would flow better following the order of heat pipe placement}}

{{History|0.15.0|
* Introduced}}

== See also ==
* [[Power production#Nuclear power|Power production]]
* [[Heat exchanger]]

{{ProductionNav}}
{{C|Energy}}

Official Factorio Wiki - User contributions [en]

Heat pipe