Nuclear Reactor

The Nuclear Reactor is the ultimate advancement in IndustrialCraft energy generation technology. Customizable, extendable, extremely powerful, only needing re-fueling once every few hours, and capable of obliterating an entire base if used carelessly. As Alblaka would have it, the ultimate in "HAYO!"

The energy production, and safety, of a Nuclear Reactor is dependent upon the pattern of components placed in it. Each component in a Reactor will interact with either its four adjacent components, the reactor "hull" itself, or both.

Safety

Note: It is highly recommended that any intended Reactor design be first tested using the Reactor Planner.

The critical safety concern when designing Nuclear Reactors is heat. Nuclear fission gets hot. And that heat has to go somewhere. Heat is produced by Fuel Cells, and either dumped into adjacent Heat Vents, Coolant Cells, Heat Exchangers, or Condensators; or if none are available, into the reactor hull itself. Every heat-absorbing component has a maximum heat limit, displayed by its durability bar. If a component reaches its heat limit, it will be destroyed. (When this happens, it usually leads to more components failing, and very quickly the entire reactor exploding.)

The reactor hull itself can by default hold 10,000 heat units. This limit can be increased by placing Reactor Platings in the design. As the reactor hull heats, various negative effects start to occur on its surroundings.

When a Reactor reaches 40% of its heat limit, random blocks within a 2-block range of the Reactor will start catching fire
When a Reactor reaches 50% of its heat limit, Water blocks within that area will start to randomly evaporate
When a Reactor reaches 70% of its heat limit, entities within a 3-block range of the Reactor will start taking damage from the radiation
When a Reactor reaches 85% of its heat limit, random blocks within 2 blocks of the Reactor will start transforming into Flowing Lava. Blocks with high Blast Resistance values (such as Obsidian or Reinforced Stone) can still survive this.
If a Reactor ever reaches its full heat limit, it will explode extremely violently, with the explosion force depending on the number of fuel cells it contains.

Design

The Nuclear Reactor itself can be either a single block, or an up-to-7-block multiblock structure. The structure is built by placing the Nuclear Reactor block, and then placing up to six Reactor Chamber blocks, one on each side of the Reactor itself. The Nuclear Reactor on its own contains a 3x6 inventory; each additional Chamber adds another column, to a maximum of 9x6 slots.

There are several types of Reactor components.

Fuel Cells are made of either Uranium or Uranium and additives. (The five types of Enriched Uranium are made in the Uranium Enricher.) Fuel Cells emit heat and generate EU.
Coolant Cells absorb heat emitted by adjacent components and store it.
Condensators also absorb heat, however rather than being cooled, they are in stead repaired by removing them from the reactor and crafting them with either Redstone or Lapis Lazuli.
Heat Packs generate 1 Heat/tick and emit it to nearby components. Heat Packs will not emit heat directly to the Reactor hull (only adjacent components), and will stop generating heat when the reactor hull reaches a temperature equal to 1000 times the number of Heat Packs stacked in one slot. Unlike other reactor components, Heat Packs are stackable, up to 64.
Heat Vents absorb Heat emitted by adjacent components (however they will not draw in heat themselves) and dissipate it. Some Vents also absorb heat directly from the reactor hull.
Spreading Vents do not absorb heat. In stead, they remove heat from all of their adjacent components.
Heat Exchangers attempt to equalize the heat stored within themselves and adjacent components.
Reactor Platings increase the heat limit of the Reactor hull, increase the temperature levels at which a reactor's surroundings catch fire, and depending on their type either increase or decrease the force of a meltdown explosion.
Neutron Reflectors cause adjacent Uranium Cells to generate additional heat and EU. This allows for more fuel-efficient Reactor designs.
Depleted Isotope Cells generate the same heat as regular Fuel Cells, but no EU. If they are placed adjacent to other Fuel Cells, they will re-charge themselves, and when fully charged can be crafted into Fuel Cells. A reactor that re-charges Depleted Cells is known as a Breeder Reactor.

Reactor Ticks and Fuel Cell Pulses

Unlike most tile entities, Nuclear Reactors only functionally tick once per second (once per 20 ticks). On those ticks, called Reactor Ticks, Fuel Cells emit Heat and other components absorb and remove it. EU output, however, is continuous; each Reactor Tick determines the Reactor's EU output rate for the next second.

Fuel Cells "pulse" once per Reactor Tick, while a Reactor has an active Redstone signal. (A Reactor will not produce energy without a Redstone signal.) With each pulse, the Fuel Cells generate heat and EU, and fire a neutron (not visible) at all 4 of their adjacent components. If a Fuel Cell is struck by a neutron, it will produce an additional pulse of heat and EU. If a neutron strikes a Reflector, it will be returned to its source, causing that source to pulse again. Each time a Fuel Cell emits a neutron burst or a Reflector reflects a neutron, its durability will decrease by 1. When a Fuel Cell reaches 0 durability, it has a 1/3 chance to transform into a Near-Depleted Fuel Cell, and a 2/3 chance to simply be lost. When a Reflector reaches 0 durability, it is destroyed, unless it's an Iridium Neutron Reflector.

Depleted Isotope Cells also pulse, however their pulses do not emit energy or neutrons. However, each time they are struck by a neutron, they produce an additional pulse of heat, and gain 2 points of durability. This durability charge rate can be further increased by increasing the heat of the reactor hull. For each 3000 heat in the Reactor Hull, each neutron absorbed will cause a Depleted Isotope Cell to recover an additional point of durability. (0-2999 heat, 2 points, 3000- - 5999 heat, 3 points, etc.) Heat Packs can be useful for maintaining a specific reactor temperature. When a Depleted Isotope Cell reaches full durability, it stops pulsing and transforms into a Re-Enriched Cell, which can be crafted with Coal Dust back into a working Fuel Cell.

Fuel Cells can also be crafted with Dense Copper Plates to form Double and Quad Fuel Cells. These Cells pulse and emit neutrons as if they were a 2x1 pair or 2x2 square of Fuel Cells, but occupy only one inventory slot. This allows for highly fuel efficient, but very hot, Reactor designs. (A 2x2 square of Quad Uranium Cells produces 960 heat. That amount of heat is difficult to handle.) When depleted, a Double or Quad Fuel Cell has a 1/3 chance to transform into either 2 or 4 Near-Depleted Fuel Cells, and a 2/3 chance to be lost.

Fuel Efficiency

As mentioned, Fuel Cells lose durability once per second, when they release neutron bursts. However, they emit heat and EU every time they release or receive a neutron. As such, clusters of Fuel Cells produce more EU per tick, and EU in total, than individual fuel cells, over their full life span. The only problem is accounting for the large amounts of heat these clusters produce. The theoretical maximum efficiency of a Reactor is 7 (each Fuel Cell produces 7x its base EU per tick and in total), which can be achieved by using only Quad Fuel Cells, and surrounding all Quad Fuel Cells with only either other Quad Fuel Cells, or Neutron Reflectors.