....There's no real way to measure steam output/consumption that I've found.
You can measure steam output of a reactor by using a pipe pump. Once a reactor-cycle has completed (x pellets in each core have been spent), power the pump (its cheap) to "drag" all the steam into one steam line segment. Use the transducer to measure that amount of steam. It should be accurate to better than +/- 1% for a normal-sized steam network (some tiny traces of steam get stuck in the pipes all through your network)
I'm not sure how control rods work tbh. That reactor setup runs perfectly fine without. But at a guess, removing a few cores to put in control rods would significantly reduce neutron production.
Reactor cores work by firing neutrons at each other, which produces more neutrons. If you put a control rod between two reactor cores, and drop it into place, it stops the neutrons from hitting the other cores. This cools the reaction and thus your reactor, and reduces fuel consumption.
You could leverage control rods in your reactor a few ways. One would be to replace the "central" reactor core of your 3x3 with a control rod. It would stop the "cardinal" reactors from reacting to each other if needed. (btw, as it stands that core will be significantly hotter than the others, fair warning)
Another way you could use them: your reactor has an "inside" and "outside" ring of boilers. If you replaced the "inside" ring with control rods, and surrounded your "outside" ring with neutron reflectors instead of concrete, you'd have a much more powerful reactor: the neutrons which would normally get "wasted" would bounce back in, except when your control rods are lowered.[DOUBLEPOST=1408988304][/DOUBLEPOST]
HP Turbine production tops out at 8.95GW
Unless you're using ammonia, which is good for considerably more.