The technology isn’t exactly the same, but it’s extremely similar.
In Texas, they’ll probably be building the AP-1000s since both Comanche Peak and STP are Westinghouse PWRs.
Every nuclear plant in the US up till now has been a custom design. The advantages of the AP-1000 and the ABWR are that they’re already approved by the NRC. All the utilities have to do is get the building permits and then prove they built it according to design.
You ain’t kidding about the custom part. I remember my Father(worked for TXU) telling me about how the Government couldn’t make up their mind on the water/steam piping on Commanche Peak. TXU had to rip it out and replace it a few times. It jacked the price tag up pretty high to the effect that TXU had to go running to the PUC for a rate increased. I think that experience burned TXU from making any other attempts at building another nuclear facility. That and it saddled them with a huge debt, which TXU was always more in debt than other energy companies like Reliant.
At the hearings, the same issues that were brought up at other plants were brought up again and again and recognized as legitimate by the hearing judge who was shopped for by the anti-nuke nuts from the east coast or west coast.
You design something with a safety margin of 5 to accommodate unknowns and future changes. The NRC then revises the local seismic site accelerations reducing the safety factor to 4.5 and the NRC tells you to never mind the original margin, redesign or re-qualify to the original design margin of 5.
A generic plan design will help but the crazies will still find judges who will hear them and impose absurd requirements for the political purpose of delaying the plants, driving up costs and cancellation.
The problem is political and until these enemies of America
and our secure future are routed and disposed of, we will endlessly spin our wheels on progress.