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Reactors consume one fuel cell per 200 seconds regardless of the thermal load. Reactor fuel use should be proportional to thermal demand. This means a 'shut down' base can not be completely shut down since the reactor plant will consume all of its fuel significantly faster than it would have if all machinery was sitting idle.

I'm assuming this is a bug because, in my observations, care was taken to make heat load function realistically in many other ways. Reactors that are out of fuel will cool down at a rate proportional to steam demand/power generation (cool down faster with higher electrical load). Fuel should really only be expended while heating up the reactor/heat pipes/heat exchangers, or while those heat exchangers are producing steam. A reactor with no heat load should not consume a significant amount of fuel. A reactor plant does not consume considerable fuel just to stay hot. Reactor fuel consumption is rated in 'full-power hours', meaning that if you ran the reactor at half of its rated power, the fuel would last twice as long. In Factorio, a fuel cell should only be expended in 200 seconds if the reactor is producing a full 40MW. At lower power levels, fuel should last longer. A reactor with no heat connections should stop consuming its fuel cell after it has heated to 1000 C.

Understood that circuit networks can probably help this by only loading fuel into enough plants to handle the current demand, but this should not be a problem that the player has to solve since that's not how heat production / nuclear fuel consumption works.

malventano wrote:Reactors consume one fuel cell per 200 seconds regardless of the thermal load. Reactor fuel use should be proportional to thermal demand. This means a 'shut down' base can not be completely shut down since the reactor plant will consume all of its fuel significantly faster than it would have if all machinery was sitting idle.

I'm assuming this is a bug because, in my observations, care was taken to make heat load function realistically in many other ways. Reactors that are out of fuel will cool down at a rate proportional to steam demand/power generation (cool down faster with higher electrical load). Fuel should really only be expended while heating up the reactor/heat pipes/heat exchangers, or while those heat exchangers are producing steam. A reactor with no heat load should not consume a significant amount of fuel. A reactor plant does not consume considerable fuel just to stay hot. Reactor fuel consumption is rated in 'full-power hours', meaning that if you ran the reactor at half of its rated power, the fuel would last twice as long. In Factorio, a fuel cell should only be expended in 200 seconds if the reactor is producing a full 40MW. At lower power levels, fuel should last longer. A reactor with no heat connections should stop consuming its fuel cell after it has heated to 1000 C.

Understood that circuit networks can probably help this by only loading fuel into enough plants to handle the current demand, but this should not be a problem that the player has to solve since that's not how heat production / nuclear fuel consumption works.

Thanks for the report,

This is a intended gameplay feature,
Once a nuclear reaction is starting in the fuel cell, you can't stop or slow it down,
You either use the power or it goes to waster

Understood if this is an intended feature, however, this opens up ways to cheat the system. One could simply lay out a bunch of heat pipes and create a large thermal battery, and only cycle reactors to maintain the temperature of the large chunk of heat pipes above 500C.

malventano wrote:Understood if this is an intended feature, however, this opens up ways to cheat the system. One could simply lay out a bunch of heat pipes and create a large thermal battery, and only cycle reactors to maintain the temperature of the large chunk of heat pipes above 500C.

I was surprised to see that the reactor didn't start cooling off as soon as the fuel ran out. The amount of energy needed to heat the reactor back up to the operating temperature of the heat exchangers would make running out of fuel disadvantageous as well.

Nemoricus wrote:

malventano wrote:Understood if this is an intended feature, however, this opens up ways to cheat the system. One could simply lay out a bunch of heat pipes and create a large thermal battery, and only cycle reactors to maintain the temperature of the large chunk of heat pipes above 500C.

I was surprised to see that the reactor didn't start cooling off as soon as the fuel ran out. The amount of energy needed to heat the reactor back up to the operating temperature of the heat exchangers would make running out of fuel disadvantageous as well.

The reactor does cool down as soon as it runs out of fuel, but the cooldown rate is proportional to thermal load, so if it has no thermal connections, its own thermal mass will retain the heat. Same way water temperature in a boiler will remain hot if it is out of fuel but has no steam load. Makes sense.

I started a thread over in balancing since this is a currently intended game mechanic that otherwise invites ways to cheat the system.

malventano wrote:

Nemoricus wrote:

malventano wrote:Understood if this is an intended feature, however, this opens up ways to cheat the system. One could simply lay out a bunch of heat pipes and create a large thermal battery, and only cycle reactors to maintain the temperature of the large chunk of heat pipes above 500C.

I was surprised to see that the reactor didn't start cooling off as soon as the fuel ran out. The amount of energy needed to heat the reactor back up to the operating temperature of the heat exchangers would make running out of fuel disadvantageous as well.

The reactor does cool down as soon as it runs out of fuel, but the cooldown rate is proportional to thermal load, so if it has no thermal connections, its own thermal mass will retain the heat. Same way water temperature in a boiler will remain hot if it is out of fuel but has no steam load. Makes sense.

I started a thread over in balancing since this is a currently intended game mechanic that otherwise invites ways to cheat the system.

The reactor will not cool down below 500 C when it runs out of fuel, no matter how much thermal load there is. This lack of inherent cooling off is what I'm referring to.

Well, that also makes sense, since the heat exchangers stop producing steam below 500C, meaning there is no longer anything removing heat from the reactor. I think you're referring to losses to ambient, but the game doesn't implement that anywhere else, so I wouldn't expect it to have to deal with it here.

Yeah well... I think even if it is an intended feature it would be great if there was a way to at least throttle the reactor... like control rods or something that may be interacted with using the Circuit Network or so.


Also the way the neighbouring system works should probably be changed too. It should be more about reaching critical mass... so every reactor within a certain radius/reach (like an area of effect) boosts all other reactors due to the increased amount of neutrons, and the other reactors then in turn boost back... rinse and repeat... with exponential increase of power output over time (without an upper limit) at increasing speed/cost of Fuel drain... and if you don't want it to get out of hand by wasting more and more Uranium you have to throttle the reactors with control rods/neutron absorbers that can be placed between reactors, effectively allowing different reactor designs. Or something like that.

At least the way it is currently it feels a bit weird... and doesn't really encourage build diversity when it comes to reactor layouts. (Yeah there's diversity when it comes to heat exchangers/steam turbines etc, but not with the reactors itself). Currently it's basically 2x2, 2x3, 2x4, 2x5, 2x6 ... and so on because of how the current neighbouring effect doesn't allow anything else.



Currently I have given up trying to control the fuel insertion of the reactors because it's not worth it when a 6 reactor core plant barely uses 120-150 U-238 per ingame hour. It will take several hundreds of hours to deplete some of the 100-200k+ Uranium patches in my map.

I was able to blow through a patch overnight with an otherwise idle factory - because I wasn't aware that the reactors would consume fuel at the max rate constantly. I hadn't yet researched the refinement process so I was only making 235 from the initial dice roll.

malventano wrote:I was able to blow through a patch overnight with an otherwise idle factory - because I wasn't aware that the reactors would consume fuel at the max rate constantly. I hadn't yet researched the refinement process so I was only making 235 from the initial dice roll.

Yeah well, that's ugly indeed.

To be honest I didn't even start using Nuclear Power until I had researched the Kovarex Enrichment and got my 40 U-235 together... because I somehow expected it to be a lot of gambling to resort on the initial dice roll. I was already happy when I got my 40 U-235 to start the Kovarex Enrichment... and I produced almost 5000 U-238 in the process which I used to buffer in a chest for the time being until I reached the 40 U-235.

I was pretty occupied with fixing other stuff in the meantime anyways but it took me like 5-6 hours before I realized that it takes forever, after which I started to beaconize the process.

Yea... can't we fix that initial diceroll to simply take 20 Uranium, then produce the refined products in a 19/1 ratio? Kovarex seems needed if you want to keep a reactor supplied. I used Productivity modules in the Uranium refiners, figured from my experiences with the Nukular mod that I'd need that enrichment process early to get a fuel loop going - it didn't take hours for me and I vaguely recall only filling half a steel chest with U-238. Maybe I was lucky, maybe productivity modules improve your U-235 chances. I didn't watch them closely, does the bonus product just spit out an extra of each or does it do another diceroll...?

Aeternus wrote:Yea... can't we fix that initial diceroll to simply take 20 Uranium, then produce the refined products in a 19/1 ratio? Kovarex seems needed if you want to keep a reactor supplied. I used Productivity modules in the Uranium refiners, figured from my experiences with the Nukular mod that I'd need that enrichment process early to get a fuel loop going - it didn't take hours for me and I vaguely recall only filling half a steel chest with U-238. Maybe I was lucky, maybe productivity modules improve your U-235 chances. I didn't watch them closely, does the bonus product just spit out an extra of each or does it do another diceroll...?

I know for sure that the productivity modules don't change anything about it... I use them everywhere, still it took me more than a chest full of U-238

Aeternus wrote:Yea... can't we fix that initial diceroll to simply take 20 Uranium, then produce the refined products in a 19/1 ratio? Kovarex seems needed if you want to keep a reactor supplied. I used Productivity modules in the Uranium refiners, figured from my experiences with the Nukular mod that I'd need that enrichment process early to get a fuel loop going - it didn't take hours for me and I vaguely recall only filling half a steel chest with U-238. Maybe I was lucky, maybe productivity modules improve your U-235 chances. I didn't watch them closely, does the bonus product just spit out an extra of each or does it do another diceroll...?

Needing to enrich adds interesting complexity to the process. However, I do agree that the randomness is undesirable and confusing to new players. My own suggestion is changing the recipe to require 1000 ore and output 99 U-238 and 1 U-235. This retains the need to enrich while removing randomness.

malventano wrote:Understood if this is an intended feature, however, this opens up ways to cheat the system. One could simply lay out a bunch of heat pipes and create a large thermal battery, and only cycle reactors to maintain the temperature of the large chunk of heat pipes above 500C.

I think the storage tanks should blow up if you try to put steam inside.

Matthias_Wlkp wrote:

malventano wrote:Understood if this is an intended feature, however, this opens up ways to cheat the system. One could simply lay out a bunch of heat pipes and create a large thermal battery, and only cycle reactors to maintain the temperature of the large chunk of heat pipes above 500C.

I think the storage tanks should blow up if you try to put steam inside.

I dunno man. I think it's freaking awesome - especially how the tank level is backwards (steam fills the top first and moves down as the tank fills).