Perspective on Nuclear Construction

by Will Davis

Indian Point Unit 1 under construction.  Photo in Will Davis library.

Indian Point Unit 1 under construction. Photo in Will Davis library.

A new article published by the Korea Times, entitled “Korea is second-fastest nuclear plant building country: IAEA” points up the fact that South Korea has historically built its nuclear plants on the average of 56 months (from construction start to commercial operation.)   The article points up the fact that two nations normally thought of as nuclear power leaders and pioneers, France and the United States, have historically seen this average way up at 126 months and 272 months, respectively.  I’d like to offer some comments — not a defense, but just some comments — on those numbers to provide perspective, since they’re pretty long and, in the case of the U.S., extremely long.


The French nuclear program began, as did so many others, with some questions about which type of reactor would be best suited to the varied needs of that nation.  It was a short time before the Pressurized Water Reactor (PWR) was settled upon as a national standard and built in increasing numbers to ensure the energy independence of the country.  Orders for the first standardized type, known as the CP1, began in 1974.  Even as these were under construction and planned, a design revision was made that rearranged a significant portion of the power plant without changing intrinsically the important systems contained therein. This was the CP2 series ordered starting in 1976.  The CP2 series showed a wider variance in construction times, unit for unit, than did the CP1 series.

All of these were not yet complete — and in fact the last of the CP1 units not even yet ordered — when a newer, much larger and different design, known as the P4, was ordered in 1977.  It’s important to note that the French had at this point begun to transition from a solid national standard to having three designs of nuclear plant under construction simultaneously. Unfortunately, the P4 did not fare well in its cost to construct and no economy of scale savings were experienced.  A revised P’4 design was launched in 1978 to simplify plant arrangement and construction with the aim of reducing costs. The design was ready for order by EDF, the nationalized utility, in 1980.  Still after this, several more P’4 units were ordered.

I could go on through the N4 design in France, and the fact that by 1988 there was a very deliberate slowdown in nuclear construction as the nation reconsidered its needs and faced actual oversupply, potentially, for several years.  However, one point in comparison with the Korean standard plants now being built is clear — in Korea, which also is building nationwide standard plants, when a design revision is made, it immediately and totally replaces other plants in the pipeline.  In France, a very considerable overlap occurred, which in itself may have led to overstretching of design talent and the unpredicted economic problems (in terms of cost to construct) of the P4 series.

In the end, France was victorious in its effort to achieve a very high degree of nuclear power on its grid with about 75% of its total electricity being generated by nuclear energy.  Even with delays introduced later in the program, the program’s intent was carried out completely successfully, to the well justified pride of the industry and entities involved in France.

Palisades Nuclear Plant under construction; promotional photo in Will Davis library

Palisades Nuclear Plant under construction; promotional photo in Will Davis library


Conditions of course in the United States, with many different private and public electric utilities, architect-engineers (to design the plants), construction managers (to build the plants), and vendors (to supply equipment to the plants), were exceedingly different from those found today in Korea, and in the days of old in France, so that direct comparison isn’t particularly useful.  However, it suffices to point up the fact that a number of factors both inside the nuclear enterprises themselves (owners and all of their contractors) and outside of them served generally to drive construction times out.

Estimates of electric power demand increases for the future, which were made in the 1960’s and early 1970’s and which led to the ordering or announcement of very many nuclear plants, turned out to be quite optimistic in most cases.  The energy crises of the early 1970’s led not to a sense of the need of increased use of nuclear electricity but rather to a national sense that economy and austerity were the watchwords of the future.  As a result of this, and other pressures, the demand flattened.  However, by this point quite a number of utilities which had not cancelled their in-progress nuclear plants elected to slow construction (not wishing to abandon facilities partly built, to write off income already spent and to ‘get out of line’ for major components that were on long lead times), so that artificially the average construction time dragged out longer.

In the late 60’s, when the US Atomic Energy Commission was suggesting that a utility could expect that it could have a nuclear plant in commercial operation about six years after the award of the first contract (normally to an architect-engineer) a flood of orders coming in to the various firms involved in designing and constructing plants here began to result in a paper backlog for equipment.  For example, the large and heavy reactor pressure vessels could not just be turned out like toasters, and the general rule of ordering the vessel five years before the expected commercial operation date for the plant (actually it would be delivered well before this) began to look short.  This and other equipment delays began to push the average construction time out.  The insertion into the competitive field of foreign makes for both pressure vessels and turbine generators, as well as the early cancellation or delay of a number of plants in the pipeline, alleviated this delay somewhat prior to 1970. But then, there was a serious shock to the system.

Calvert Cliffs Nuclear Plant; from promotional brochure in Will Davis library.

Calvert Cliffs Nuclear Plant; from promotional brochure in Will Davis library.

The whole episode known generally in the business as “The Calvert Cliffs Decision” is too lengthy for inclusion here in appropriate detail, but it will suffice to say that the legal decisions over this case which forced the nuclear utilities to develop and file Environmental Impact Statements for all nuclear plants being built, in line with the National Environmental Policy Act, was a very serious blow to the schedule average.  One architect-engineer firm estimated that this process, coupled with more stringent site selection (and the narrowing of available sites on which to build plants) added more than two years to the overall schedule of building a nuclear plant in the United States.  In fact, by this time in the middle 1970’s the schedule was more like nine or ten years from first contract award to commercial operation.  Also, a licensing moratorium while the Calvert Cliffs legal decision played out did not help matters.

Much the same effect followed the Three Mile Island (TMI) accident in 1979, after which a tremendous impact was felt throughout the fields of nuclear utilities and every one of their vendors and contractors. In all reality TMI had a deeper effect on the industry than Calvert Cliffs could ever have had.  Plants still under construction after about 1980 experienced very serious delay because of this incident.

Serious complications were experienced more and more as the 1970’s wore on, as well, in the area of protest and intervention by outside parties.  Legal wrangling by outside parties, usually allied with environmental groups of the day whose leadership lived nowhere near any given nuclear plant being protested and who “shipped in” opposition, seriously delayed many projects.  Some groups even took full credit for having killed off projects, although they by themselves had no power to do this, per se.

TVA's Browns Ferry Nuclear Plant under construction, late 1960's.  This is a rare example wherein the owner also acted as engineer-constructor (although GE assisted in design because of the proprietary pressure suppression containment.)

TVA’s Browns Ferry Nuclear Plant under construction, early 1970’s. This is a rare example wherein the owner also acted as engineer-constructor (although GE assisted in design because of the proprietary pressure suppression containment.) Photo from TVA brochure in Will Davis library.

This isn’t to say that internal factors weren’t discovered.  In some cases, less than optimal design made plants or portions of plants difficult to construct. New construction methods, such as over-the-top, helped alleviate these problems. In other cases, the constructor began, or was directed to begin, construction work without having the final complete drawings from the architect-engineer — only to find that some components or structures had to be changed or modified. This led invariably to not just significant cost problems but delay as procedures had to be developed for rework of jobs which were never intended or planned for rework in the first place. Sometimes coordination between the architect-engineer, the constructor, and the utility was poor or poorly managed.  There was a little benefit obtained by some customers, who contracted firms that could act as both architect-engineer and as constructor (sometimes referred to as “engineer-constructor” or “AE-constructor), but such firms, even at the height of nuclear construction in this country, did not have the qualified manpower to take on all the jobs they were offered.

For all of these, and many other reasons, the whole situation in the United States during the years of what we sometimes today call “The First Nuclear Build” was almost constantly in flux, and was throughout its history, subjected to both external pressures and to internal complications.  The difficulties of those years first led to standardized nuclear plant drawings. Eventually, it led to whole standardized nuclear steam supply systems and nuclear plants complete. In today’s world in the U.S., a whole nuclear power plant is pre-certified by design before it is even ordered, and only customer and site-specific alterations within permissions are to be made.  Today’s new builds are still first-of-a-kind, even though they’re designed with a generation or three worth of experience.  We can, and should, hope that with continued experience in construction of today’s standardized and design certified plants that inroads will be made on that national average for time-to-construct our nuclear plants here in the United States.


ANS member Will DavisWill Davis is Communications Director and board member for the N/S Savannah Association, Inc. He is a consultant to the Global America Business Institute, a contributing author for Fuel Cycle Week, and he writes his own popular blog Atomic Power Review. Davis is also a consultant and writer for the American Nuclear Society, and serves on the ANS Communications Committee and on the Book Publishing Committee. He is a former US Navy reactor operator and served on SSBN-641, USS Simon Bolivar.

4 thoughts on “Perspective on Nuclear Construction

  1. Stephen Maloney

    Obviously, Korea’s “fast-track” construction program has been impacted by the recent scandals. Whenever I hear “partnerships” with regulators, the well-documented phenomenon of “regulatory capture” quickly comes to mind.
    I also recognize this short piece cannot provide a robust history of US construction experience. But, I think the emphasis on the Calvert Cliffs decision may inadvertently overllok the disruption associated with a naive engineering designs and ambitious construction schedules. This naiveté was as much a reflection of the immaturity of the designs as it the immaturity of safety standards the designs were supposed to satisfy.
    Recognize many plants were ordered before the US Atomic Energy Commission (AEC) thought through what safety systems were supposed to do. This is like selling and beginning to deliver a fleet of airliners without any idea what would be required for an airworthiness certificate.
    It took more than 10-years before most safety standards were initially defined – measured from the AEC’s release of General Design Criteria (proposed July 11, 1967) and subsequent publication of regulatory guidance in the form of Regulatory Guides and Standard Review Plans.
    That meant every US reactor was subject to backfits and rework.
    Key AEC rulemakings had very significant impacts and yet are not mentioned anywhere in this posting. Industry standards were also embryonic during this period (e.g., IEEE-STD-384).
    10 CFR Part 100 expanded on GDC 2 and refined the requirements applicable nuclear power plant structures, systems, and components important to safety to withstand the effects of natural phenomena such as earthquakes, tornadoes, hurricanes, floods, tsunami, and seiches without loss of capability to perform their safety functions.
    Part 100 also imposed siting requirements which relocated many sites to less populated areas. For example, Pilgrim Station was originally envisioned to be built on an island in Boston harbor. It was relocated to Plymouth MA which was lightly populated some 45 years ago.
    The Fukushima accident demonstrates what happens when safety systems are improperly designed to withstand natural phenomena. The population density near Pilgrim today is comparable to Fukushima Prefecture. Pilgrim is scheduled to shut down next year.
    10 CFR 50.46 became a final rule in 1974 and specified requirements for emergency core cooling system (ECCS) for design basis loss-of-coolant accidents. Some reactors were unable to comply with this rule without significant backfits and wisely shutdown for economic reasons.
    The Reactor Safety Study (WASH-1400) revealed further inadequacies in the GDC and the Standard Review Plan resulting in the AEC/NRC to define a series of “unresolved safety issues” (USIs) that became the subject of other rulemakings and backfits over the better part of the next decade. Among the more notable rulemakings were ATWS and station blackout. A tsunami-induced station blackout at Fukushima led to the accidents at the operating units. The tsunami also disabled cooling to spent fuel pools causing decay heat removal systems to fail.
    The hydrodynamics issues that arose in the mid-1970s led to significant backfits on primary containment at operating boiling water reactors (BWRs) as well as major rework at BWRs under construction.
    Then there was the fire at Browns Fire which led to the Appendix R rulemaking, and the accident at TMI-2. I could go on and on, but I think the point is clear.
    Construction cost and schedule can be very risky when you design a reactor to immature or nonexistent safety requirements.
    It took more than a generation of regulatory change and backfits before the inadequacies in plant designs were fully revealed. Many improvements were backfit into plants at significant cost. Notwithstanding the regulatory changes over that period, many plant designs are still vulnerable to accidents identified more than 40 years ago simply because the backfits were limited.
    Of course, one can always ignore the risk and simply “fast-track” a design-build program to standards arbitrarily defined and casually enforced. That didn’t work out too well at Fukushima.

  2. Ann MacLachlan

    A couple of comments on an interesting and useful article:

    – The CP2 series of 900-MW-class PWRs was not introduced arbitrarily, but resulted from industrial policy: the CP2 reactors were originally supposed to be BWRs, hence a new series.The design layout differed from the CP1 series due to the accommodation of an alternative turbine-generator supplier. The original CP1 series was designed around large sites (4 to 6 units) and construction was considered urgent. That was less the case for the CP2 units.

    – The introduction of the larger 1300-MW-class PWR series, P4, was aimed at improving economics and site usage. However, French nuclear safety regulators seized the opportunity (a generic safety authorization was required for the new design) to tighten safety requirements, and the increased safety margins erased scale effect savings for that series. The follow-on P’4 mini-series units did better in terms of cost, a clear example of lessons learned.

    – Construction schedules in France in the 1980s were slowed first by the election of F. Mitterrand, whose government imposed a halt of several months at five sites where construction had begun, and later by design, as electricity demand slumped and it was decided (by government, EDF and suppliers) to stretch out reactor construction schedules in order to maintain steady orders at Framatome’s (main supplier) manufacturing plants, rather than cancel orders outright.

    – On the US side, I believe that reactor construction schedules were also held up in the early 1970s by the legal issue around the adequacy of ECCS performance; it seems this delay was not as significant as the Calvert Cliffs EIS decision you mentioned.

    – As for Korea, clearly Korea’s nuclear power program benefited from early experience in the United States (as did France), having well-tried reference plants on which to base their reactor series. I do not know what role changing nuclear safety requirements may have played in the costs of successive series, but as you mention the industrial organization of the nuclear construction program around coherent design series, as well as the concentration of construction on a limited number of sites, certainly contributed to better cost control.

  3. Will Davis

    I cannot answer that at the moment in detail, but I absolutely suspect that the deliberate slowdowns placed on nuclear plant construction by the owners of more than one plant in the US (quite aside from the regulatory-induced slowdowns) are a significant part of this average.

  4. R. Stuart Bondurant

    What is the source of “…France and the United States, have historically seen this average way up at 126 months and 272 months…” A US average of 272 months (22.6 years) seems longer than I recall. Is this taking into the average plants like Watts Bar II, that were in mothballs for years?