(I just skimmed the last several messages, so forgive me if I misunderstood anything.) @chrisl Try calculating the consumption over the entire time that you are away from your vessel, i.e. the entire 2 days. I think you will find that the converters are not behind by the entire amount, but only some time less than a 24-hour day (i.e. 84600 seconds or the MaxDeltaTime). The issue you are seeing is caused by multiple independent systems interacting*, with no way to determine which runs first. So the converter could end up running first, and trying to recycle a "days worth" of CO2 exhaled by the Kerbals except the calculation for the Kerbals has not run yet! So there is no CO2 yet to be recycled. Then the Kerbal calculations run, and they breath in the Oxygen and exhale the CO2. Then the converter runs again, but it already calculated for a days-worth so it just calculates for the remaining time minus the days-worth (again limited to MaxDeltaTime).** You should never see anything get more than MaxDeltaTime seconds out of sync. You can try changing the MaxDeltaTime in the configuration file and see how that effects everything. Just keep in mind that you can set the MaxDeltaTime too low such that it cannot keep up when time warping and it can take too long to catch up if you were away for a significant of in-game time. At 100,000x time warp, 100,000 seconds pass per real-time second, or 4,000 seconds per physics frame (0.04 seconds). If MaxDeltaTime is set below 4000, then the mod will not be able to keep up with the time warp rate. An in-game Kerbal year is 9,201,600 seconds long (426 days * 6 hours). The default settings (86,400 seconds per physics frame) will make it take 4.26 seconds per year to catch up. At 4000, it will take 92 seconds (~1.5 minutes) to catch up per year. If you do change MaxDeltaTime, please share your findings with everyone. I could fix this by making all of the calculations run from one central "controller", but that limits the ability for other people to make a part and have it "just work" with my mod. They would have to use one of my classes (TacGenericConverter) or use some complicated "registration" technique. None of the stock parts (i.e. converters or drills) would work. BTW, DBowman pretty much answered your question on 5 Oct. Thanks DBowman and damerell and everyone else for helping answer questions! Sorry I have not been around much lately. Also, Thank You to everyone for expressing your support for this mod. I am not abandoning it, but I will be asking for some help soon because I do not have the time to keep up. * The other mods you are comparing to, like the fuel boil-off, only have one system to worry about and so do not have to deal with the complexity of multiple independent systems interacting. ** The opposite could also happen: the Kerbal calculations run first, so they consume O2 and generate CO2. Then the converters run, and they recycle the CO2. If you have at least a days worth of O2 for the Kerbals, then everything is fine. But if you do not, then the calculations would think the Kerbals have been deprived of oxygen and could be killed before the converter has a chance to run! (Note the Kerbals are not actually killed until the next physics frame to give the converters an extra chance to run so I don't erroneously kill the Kerbals.) - - - Updated - - - See my spreadsheet, especially the section about Recycling, starting at line 313: https://docs.google.com/spreadsheet/ccc?key=0Aioc9ek3XAvwdGNsRlh3OVhlbTFBR3M4RW0zLUNTRFE&usp=drive_web#gid=0 The short explanation is: to avoid dealing with intermediate resources, my recyclers combine multiple reaction steps or reverse the order. Sabatier reaction: First split some water to get oxygen and hydrogen gas. Then use the hydrogen in the Sabatier reaction to recover the O2 (as water) from the CO2. This uses twice the water that it generates and generates methane gas as waste. 4H2O -> 2O2+4H2, then 4H2+CO2 -> CH4+2H2O Bosch reaction: CO2 + 2H2 --> C + 2H2O, then H2O --> 2H2 + O2, C is waste Note that in your equation, you still need to split the water to get the oxygen (for breathing). Also note: I did not find good values for the energy required or generated by the different reactions, so the power usage may be off, but the rest of the calculation should be correct.