Steam Boiler (Railcraft)

Steam Boiler
	32px ; The Solid Fueled Firebox
Name	Steam Boiler
Source Mod	Railcraft
ID Name	Unknown
Type	Structure
Stackable	Unknown

Steam Boilers[edit]

The Steam Boiler is the multiblock, heavy duty power generator of Railcraft. It consumes water and fuel to produce Steam: a fluid required to power various Railcraft engines and machines.

Steam Consumers[edit]

Hobbyist's Steam Engine (10 Steam/tick)
Commercial Steam Engine (20 Steam/tick)
Industrial Steam Engine (40 Steam/tick)
Steam Turbine (320 Steam/tick)
Steam Oven (32 Steam/tick)

Steam Production and Boiler Types[edit]

Detailed operational information about Steam Boilers can be found here.

Steam Boilers come in different types and sizes:

Liquid Fueled Firebox or Solid Fueled Firebox: determines the type of fuel the Steam Boiler accepts
Low Pressure (LP) or High Pressure (HP) Boiler blocks: LP offers better fuel efficiency while HP offers more steam per volume.
Boiler block size WxDxH: 1x1x1, 2x2x2, 2x2x3, 3x3x2, 3x3x3, 3x3x4. Each Boiler block generates 10 (LP) or 20 (HP) units of steam per tick. Larger boilers are more effective in fuel consumed for steam produced, but require more fuel for their longer heat ups. (There must be 1 block of space on all sides, e.g. a 2x2x2 boiler would need to be centered within a 4x4x4 space. This is excluding the piping/tesseracts/chests.) You can upgrade the boiler size in the middle of its operation without exploding, but it will NOT retain the heat value, so it will reset to zero and begin anew.

Water consumption for a 3x3 liquid firebox is a flat 5mB/tick (100mB/sec), independent from steam production (FTB Unleashed v1.1.3). A single Aqueous Accumulator can supply enough water for 5 maximum size boilers.

Warning: Adding water to a heated up Steam Boiler when its water tank is empty will cause a devastating explosion. Place the water supply within the same chunk as the boiler, or use chunk loaders, to prevent interruption of the water supply. To recover a dry boiler simply break a tank block then replace it to immediately cool and empty the tank.

Heating Up[edit]

Steam Boilers need a considerable amount of fuel and time to heat up. For example: A maximum size high pressure Steam Boiler takes 5 real hours to heat up. Heat Up times are dependent both on size of the boiler (number of tank blocks) and high/low pressure. The table below shows the heat-up time in seconds for boiler size. As 5 hours is a really long time to run the boiler at lower heats (and hence lower efficiencies) it is a good idea to make a Refined Firestone and charge it up with lava - when this is used as fuel in a Solid Fueled Firebox, the boiler heats up in minutes rather than hours.

Heat Up Time in Seconds (FTB Infinity for Minecraft 1.7)
Boiler Dimensions (Total Volume)	Low Pressure	High Pressure
1x1x1 (1)	226	457
2x2x2 (8)	1807	3656
2x3x2 (12)	2711	5484
3x2x3 (18)	4067	8227
3x3x3 (27)	6101	12340
3x4x3 (36)	8135	16454

High Pressure vs Low Pressure[edit]

Contrary to popular belief, High Pressure Boilers are not more efficient than their Low Pressure Counterparts if the volume of the boiler held constant. In versions of Railcraft 8.3.0.0 and later, High Pressure Boilers, despite often being more efficient in real life, are less efficient in game than Low Pressure Boilers. They no longer require massive amounts of fuel to heat up, but there is a small efficiency penalty, with a 36HP at full heat consuming roughly 28% more fuel per unit steam than a 36LP. Fuel consumed increases slightly as temperature increases, but the difference isn't very large. Therefore, if maximum steady-state efficiency is desired, one should strictly use 36LP boilers.

The advantage of high-pressure boilers now comes in their power density, producing twice as much steam per boiler block compared to low-pressure boilers, reducing the amount of space and resources (mostly iron/steel) needed for the same amount of steam. The only difference in cost between a 36HP and 36LP is converting 72 iron into steel. This allows one to save quite a bit of iron by using 36HP boilers. In addition, high-pressure boilers reduce both the amount of space required for boilers and the load on the server. Therefore, high-pressure boilers can still be quite attractive if fuel is not in scarcity.

Older Version Notes[edit]

In versions of Railcraft prior to 8.3.0.0, boilers behaved differently. They produced their full amount of steam as soon as they reached 100 degrees, rather than only producing their full amount at maximum heat. Secondly, at full heat, HP boilers consumed fuel exactly at twice the rate of LP boilers, meaning that, ignoring heatup costs, they were equally efficient in terms of fuel consumed per steam produced. However, boilers required very large amounts of fuel to heat up, initially consuming fuel at 9 times the normal rate, with fuel consumption decreasing linearly as the boiler heated up. Since HP boilers take twice as long to heat up, and consume fuel twice as fast, this meant that HP boilers required four times as much fuel to heat up.