The nuclear power plants in service today were conceptually designed and developed during the 1960s. At that time, it was deemed necessary to achieve maximum efficiency and minimum cost in order to compete successfully with coal-or oil-burning plants. Safety features were exemplary for that era, and even for current safety practices in other industries. But they were not up to present-day demands for super-super safety in the nuclear industry.The latter were priced at 15% of their present cost and used fuel that was very cheap by current standards. In order to maximize efficiencies in the nuclear plants, temperatures, pressures, and power densities were pushed up to their highest practical limits.Nuclear Regulatory Commission required that new safety equipment and procedures be added on as "regulatory ratcheting." The amount of labor and materials for these add-ons exceeded that for the plant as originally conceived.

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