Factorio Forums

I've just unlocked the Kovarex Enrichment Process, and I'm not sure whether it's something I should prioritize right away. At the moment, my factory is producing enough U-235 for a small nuclear power setup, but progress feels slow, and I'm wondering if rushing Kovarex would make a noticeable difference or if it's better to focus on expanding science and launching my first rocket instead.

From what I've read, Kovarex becomes extremely useful once it's running, but it also requires a decent stockpile of U-235 before you can even start. I'm worried about spending time setting everything up only to realize it wasn't really necessary at this stage of the game.

For those who've completed several playthroughs, when do you usually research and build your first Kovarex setup? Do you rush it as soon as possible, or wait until uranium production becomes a bottleneck?

Alternatively you can just expand uranium processing and store the U238 for now, but kovarex enrichment is a big convenience.
I would focus the research and start saving for 40 U235 now just to be able to build a setup that does not have to change anymore.

Having the benefit of experience, I tend to start mining and processing uranium long before I plan to do anything with it, so that I have a good sized U-235 stockpile by the time kovarex is researched, and can afford to spend a few rocks on other things without causing a delay in setting up kovarex.

Waiting until kovarex is researched is too late for that, but the principle is still there: you can set up a lot more uranium mining and processing now to start building your stockpile.

Cutting your current U-235 use will speed up the process, of course, so there is a trade-off there, but it's just the difference between doing kovarex "later" and "later than that".

Waiting until uranium processing is a bottleneck, though, sounds far too late: you'd have to actually cut your U-235 usage in order to generate a surplus to stockpile for kovarex. This would be a serious sacrifice if that means, for example, you would have to turn off most of your power plant -- and thus most of your factory -- to cut back U-235 usage.

Generally I build just enough centrifuges and drills to have about twice as much U-235 as I need to power my base. That also helps at the start when you might otherwise get too long stretches with no U-235 coming out. But it slowly builds a stockpile that can then be used for Kovarex processing.

Personally I wouldn't build a huge setup for rushing it. Especially if you have Space Age and nuclear is just an intermediate technology. Maybe if you want to do a megabase speedrun and can't wait even a few minutes...

Kovarex enrichment isn't just about getting amounts of U-235, it's also (if not more) about not getting that growing pile of unused U-238 you don't have any consumer for. To keep uranium balanced as a whole, you need to use kovarex enrichment.

I start uranium processing with about 20 centrifuges and let it process uranium ore into chests. As soon as 40 U-235 accumulated, I stop ore supply and raise an alert with the programmable speaker. This takes about 1 hour and results in 40 U-235 and about 5674 U-238 - slightly more than one full chest.

In this hour, I build the infrastructure for fuel supply that includes kovarex and the first reactor power plant itself (my starting reactor setup is usually a 2x2 plant with 480 MW). Usually, it's faster to get to 40 U-235 than to complete the reactor.