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New here. I wanted to see if I could throttle reactors without relying on steam tanks. This is the setup I came up with. Copy blueprint

It detects whether the first turbine on the last exchanger has steam by switching between the main network (left power pole) and a single-accumulator network with a small power draw from lamps. I initially tried without the power switches, but network priority for a turbine on two networks depends on pole build order, which is an issue during brownouts.

It works by supplying the main network until the accumulator hits 99%, then switching to powering the accumulator (by itself). If it is unable to power the accumulator, it will drop to 98%, signalling a reactor reload (left lamp) and turning off the right lamps (to avoid draining completely). Supplying the main network when the accumulator is at 100% is critical for draining the 200 buffer steam in the turbine.

Since I'm relying on a heat differential in my heat pipes to leave a power buffer during reloads, I'll stick an extra turbine on the last exchanger so it's colder even when all turbines are throttled and the reactor is off. For really big setups, I can connect more first-turbines-on-last-exchangers to the same network to avoid 1000 degree hot spots from uneven power draw.

In a conventional steam-controlled regulated nuclear power design, the steam tanks serve two purposes. They detect a shortage of steam (and therefore of heat), but they also store energy to cover the time lag between inserting a fuel cell and steam production actually recovering to its maximum rate. They store lots of energy: one tank holds nearly 500 times as much energy as an accumulator.

Your design might work in principle, but to work in practice, without brownouts, it's going to need a large number of accumulators. (At a guess, maybe as many as 100 accumulators per heat exchanger.)

This setup stores energy in the heat pipes. The accumulator isn't used as a buffer, just a temperature sensor.

HamsterBoo wrote: Sun Jul 14, 2024 12:14 am This setup stores energy in the heat pipes. The accumulator isn't used as a buffer, just a temperature sensor.

The heat pipes can indeed store lots of energy (the equivalent of several hundred accumulators per heat exchanger). But by the time the accumulator starts to drain they already have, by definition, insufficient to keep all your turbines going. And from the moment you add fuel to the reactor it takes tens of seconds before the furthest heat pipes start to increase in temperature again. If you want to maintain 100% energy output you have to cover those tens of seconds with some other stored energy, and without steam tanks that means lots of accumulators.

Any fuel-regulated nuclear plant should be able to withstand the following stress test:

1. Run the plant with a very low demand (say 10% of maximum) for long enough that you are just about to trigger a fuel load. At this point your heat pipes will be as cold as they are ever going to get.
2. Just before (or even just as) the load triggers, increase the demand to maximum (100% of output).
3. Check that demand remains satisfied for at least the next full fuel cycle (200s).