Watz Power Plant

The Watz Power Plant is a fission based nuclear reactor that sits beyond the RBMK and PWR in progression but before fusion. It is quite similar to the ZIRNOX reactor in the sense that it is (mostly) a single assembled unit into which fuel is placed and then reacts as opposed to a modular design style of other reactors. As such, it is quite simple to operate and is easy to run but unlike the ZIRNOX, it is incredibly expensive to construct and also produces difficult to deal with waste products. As well as this, it produces very little power for its position in the game's progression and aggressively melts down if not dealt with properly, making it a poor choice for for power generation in most cases. The primary reason it is constructed is for the waste byproduct it produces, poisonous mud, which is necessary for the production of CMB steel, a progression essential component.

After construction, the Watz requires a pressure pump to be placed on top of itself, sufficient coolant in its internal buffers, and fuel pellets placed inside of its GUI to began reacting. Due to it not boiling water directly, it requires a separate heat exchanging setup in order to boil water for power production. Compared to other reactors, it depletes fuel pellets incredibly slowly, making it a practical choice for a reactor on servers and nearly useless for the purpose of fuel breeding. Another useful feature of the Watz is that individual reactors can be stacked on top of each other and simultaneously activated and deactivated with a single pressure pump, meaning that large high output stacks of reactors can be easily controlled with a single signal.

Currently, the Watz reactor has a very limited selection of fuels with the majority of fuels being derived from Schrabidium. The only non-Schrabidium fuels are MEU, MEP, and HEN. There are also absorber pellets which are designed to absorb radiation and deplete into useful isotopes and materials but due to the previously described slow rate of depletion, this is rarely ever practical compared to other types of reactors.

GUI and Operation

The GUI for the Watz reactor can be access by interacting with the machine at any point. In order to operate properly, it must have a Watz pressure pump placed on top of it, sufficient fuel inside of the reactor, cold coolant being pumped in through the top ports, and hot coolant and poisonous mud being pumped out through the bottom ports located underneath the reactor. The reactor will only operate when the pressure pump is supplied with a redstone signal. When operating, the GUI of the reactor will begin to turn red to indicate its current level of heat. This is purely visual and does not have any bearing on its operation.

Fuel Pellet Assembly. Contains the fuel pellets that react to produce heat in the reactor. Not locationally dependent like the ZIRNOX.
Fluid Gauges. Quantity of a certain type of fluid within the reactor out of 64,000mb. From left to right, each bar is for coolant, hot coolant, and poisonous mud respectively.
Pellet Configuration Lock. Enables and disables pellet configuration lock. When enabled, the current configuration of pellets in the reactor will be maintained when spent pellets are removed and new pellets are inserted automatically.
Heat Gauge. Displays the reactors current heat in TU visually as well as in numerical form when hovered over. A needle pointing to the end of the gauge does not indicate a maximum heat value or meltdown risk.
Flux Value. Displays the current amount of flux that the reactor is experiencing.

Fuel Reprocessing

Depleted Watz pellets can either be removed manually from the GUI of the reactor or automatically by any kind of item extracting block, yielding a spent Watz pellet that is cold and non radioactive, making spent fuel reprocessing much easier with the Watz than with other reactors. After extraction, spent fuel pellets can then be centrifuged directly to produce useful materials such as technetium, bismuth, and Euphemium. Despite producing useful byproducts, the sheer amount of time required to deplete a pellet combined with the fact that the Watz is so expensive to construct makes it not particularly useful as a breeding reactor.

Meltdown

If the poisonous mud buffer reaches its maximum, the reactor will melt down and explode, irradiating a wide area around it and causing fallout to fall in a small area around it. As well as this, it will spew poisonous mud in a very wide area which will then corrode any blocks that it comes in contact with, similar to corium. As such, the Watz reactor has one of the most damaging meltdowns out of all of the fission reactors available if not properly contained.

Pros and Cons

Pros

Can be stacked on top of each other for simultaneous operation and activation.
Incredibly power efficient, taking many real life hours to deplete fuels even at high fluxes.
Simple to operate and cannot melt down if properly supplied.

Neutral

Has a cool model
Requires a separate heat exchanging setup to utilize the hot coolant produced.
Depletes fuel so slowly that waste processing is not an issue but also renders it useless for breeding.

Cons

Incredibly expensive, requiring late middle game resources and large amounts of difficult to manufacture resources to build even a single one of.
Low power output, being barely above 5 MHE/s even on the powerful fuel type possible.
Has an aggressive meltdown that can destroy large areas easily and be a pain to clean up if not properly contained.
Waste liquid builds up incredibly quickly (nearly 3,000 mB/s on high power fuels) and must be solidified in order to be disposed of.

Trivia

Based loosely upon the real life pebble bed reactor design which uses a chamber of pellets enclosed in graphite to operate, but unlike the Watz, they use gas to cool themselves rather than liquid.
Beryllium and desh moderator pellets from the old version were the only ones not to be included with equivalents in the current one.