The question of why the EPR is turning out to be so much more expensive than other reactors is interesting. It looks like the EPR has overspecified safety requirements. For example: rather that just be certain the core could not melt in the event of an accident, the designers went one step further and built a core catcher in as well. Some people blame German Greens for the design complexity: (here:)
- lion :
- The EPR must meet the security demands of the ASN and, above all, the demands voiced by the German Green politician, Jürgen Trittin, who made the restrictions applying to the design and build so severe that it is almost unfeasible. So I wonder whether the EPR is not “over secure” in terms of design and build, a fact that would not even mean that it is optimally secure when it comes to operations.
It seems to me that the design was substantially complete before 1998 when the Greens took over control of the German energy ministry. See this PDF report, which has some history and these NRC slides. The design continued from 1997 to 1999 with an updated "Basic Design Report" for the EPR issued in February 1999.