Electrolyzer

This article has not been revised for the current version (U51-600112). It was last updated for LU-356355. It may contain inaccuracies.

Electrolyzer is a machine that uses electricity to split Water into its constituent Oxygen and Hydrogen.

Both gases will be output at 70 °C (158 °F), or higher if the input water is hotter.

Usage[]

The Electrolyzer requires more planning than other oxygen sources as it not only requires a constant supply of water, but the hydrogen must be handled accordingly. Another aspect is the temperature of its output. The Electrolyzer outputs at a minimum temperature of 70 °C (158 °F), so it is advised to cool the oxygen in some way before using it in the core of the colony. Alternatively the colony itself can be cooled.

Like the Oxygen Diffuser, the Electrolyzer will overpressure at a limit of 2000g.

Electrolyzers can provide a colony with oxygen for as long as water can be supplied to it. Geysers can be used as a sustainable source of water. Cool Steam Vents can also be used if the steam is condensed into water first.

The hydrogen can be dealt with in a number of ways. Running an Electrolyzer directly in a colony is not recommended, as the hydrogen causes Eye Irritation to Duplicants that come in contact with it. Placing it in an enclosed room with Gas Pumps allows it to be safely filtered out.

The simplest method of doing this is to use a Gas Filter. A disadvantage of this is that the combined oxygen and hydrogen in the Gas Vents can block each other, reducing pump efficiency. The Gas Filter also consumes large amounts of power.

Another method is to take advantage of the fact hydrogen naturally rises above oxygen. By placing Gas Pumps above and below the Electrolyzers, you can separate the outputs without using a Gas Filter. Atmo Sensors are useful to ensure pressure does not get too low, which can mix the gases.

After it is pumped out, the oxygen can be supplied to the colony via Gas Vents. Multiple vents are recommended to distribute oxygen evenly, as any one vent will stop emitting once it reaches 2000 g pressure.

The hydrogen can be used for Hydrogen Generators. If using the method without a Gas Filter, the setup can run entirely off its own generated power. This is commonly referred to as a SPOM (Self Powered Oxygen Machine).

Heat economy[]

Consider cooling water as little as possible or even dump some heat into it before delivering into electrolyzers. The input kilogram of water is more heat-dense than output kilogram of gasses, which is convenient, as it makes gasses easier to cool down afterwards.

But it gets better – Using 0 °C as the "base" temperature, 1 kg mix of oxygen and hydrogen at 70 °C carries as much heat as 1 kg of water at 19.45 °C, which means that with 19.75 °C input the electrolyzer starts destroying heat and becomes net heat negative. It will destroy 4.179 kDTU (1kg * the specific heat of water) per every degree above that, until reaching 70 °C where the outputs also begin to rise in temperature and the efficiency drops to around 3kDTUs/degree. With near-boiling 96 °C water it will stack up to 288 kDTU/s in absolute numbers, which is comparable to 3.6 AETNs.

Note, that Electrolyzer will not process water and release steam into the environment if the intake is too hot.

As a corollary, feeding water colder than 19.8 °C will create heat.

That said, the 70 °C output is sure to cook any farm relying on maintaining a temperature of 30 °C or lower without any additional heat transfer/deletion. For each gram of Oxygen it outputs the Electrolyzer outputs mass with a heat capacity of 1.308 (DTU/g)/°C. Given a Duplicant consumes 100g/s Oxygen, cooling the output of an Electrolyzer requires 130.8 (DTU/°C)/s per Duplicant, or for a 40°C difference, 5.2 kDTU/s. This is slightly more heat than is deleted by a fertilized Wheezewort in an Oxygen environment.

Tips[]

The Electrolyzer is an Algae-free way of producing Oxygen and should be researched before you run out of Algae.
Filling the Electrolyzer with anything other than Water will cause damage to it. This limitation includes Polluted Water.
The Electrolyzer has a 10 kg internal reserve, which lasts for 10 seconds under ideal conditions.
The Electrolyzer will not remove Food Poisoning or Slimelung germs within the water, and will output the germs with the Oxygen. Both germs will gradually die out in Oxygen.
Using High Pressure Gas Vents will more efficiently spread oxygen in the base (however too high pressure will cause popped eardrums which give stress, to avoid this use automation to shut off the vent at a sufficiently high pressure below 4kg).
The Electrolyzer is best combined with the Anti Entropy Thermo-Nullifier to cool down its output for very little cost in Hydrogen. In addition, it can prevent the Electrolyzer from heating too much if built close enough.

Bugs[]

Placing the Electrolyzer with two Gas Pumps on the left and right side, in the sealed room 6x2, will result in significant amount of hydrogen disappear, effectively producing only 75 g/s of hydrogen (about 66% of what it should be). The workaround is to make the room 3 tiles high (with pumps and electrolyzer placed on the ground).

Trivia[]

The tooltip is a reference to the movie "Cloudy with a Chance of Meatballs", in which a machine is invented that can turn water, into food.