Really lame how they got nerfed in the first place, with the amount of maintenance you have to do on those, at least make it reasonable compared to other power sources lol
It was technically not a nerf, it was a bugfix.
So yeah, since the only changelog I found consisted of 1.1.0 changed, I couldn't find anything to any changes for the nuclear reactor, I used this design:
http://www.talonfiremage.pwp.blueyo...vtyat23qsucdxz1l07xnymxri6ukkymwz5of0pzzcyqrk which I also found in the forum and it worked fine, but now with 1.1.1 The EU Consumption is WAY lower and it overheats...it also made BOOM, luckily I had a backup of the world before the update >_>"
So, are there any Nuclear Reactor changes?
In 1.4.7 builds of GregTech, there was a thing called the "hybrid effect". When mixing different fuel types, some combinations generated more EU than the sum of their individual parts. The single plutonium/quad thorium pairing was the strongest of these, producing 75% more EU/t than it should. This lead to the birth of "hybrid reactors" like yours.
However this was an unintended feature, and for 1.5+, Greg fixed it. Now any combination of cells generates exactly as much as it should, no more, no less. That is why you see much lower EU/t numbers - your reactor relied on a bug that no longer exists.
The reason your reactor explodes is because plutonium was changed to pulse twice per tick. Thus, it acts as if each neighbor you add were in fact two neighbors, and scales up in efficiency accordingly. Unfortunately, high efficiency ratings mean exponentially increasing heat production per EU/t generated. So even though plutonium was adjusted to produce less base heat, its extreme scaling means that any plutonium with four neighbors will run searingly hot.
A further problem of the GregTech version you get to play with now is that it is a beta build created to prepare for 1.5, with a ton of features and later adjustments missing. You basically are dealing with Greg's first attempts to rebalance his nuclear fuels, and it's actually harsher and less consistent than what he ended up settling on in the end (now in 1.5.2, GT reactors run
extremely fuel efficient, and EU/t actually went up noticably - minus the hybrid effect, of course).
I should probably just put my spreadsheet into my signature... It's not (yet) applicable to GregTech 2.90, but it shows the changes between 1.4.7 and 1.5+. Maybe I can add a section for Ultimate users though, if I end up with a free one or two hours sometime this week.
I've been on 1.5+ for a while now, myself, so I never tested that version. I will however aim to fill in the numbers for the latest Ultimate pack when I have some free time.