World Survey

2004 load factors analysed by NSSS vendors

15 July 2005

Analysis of load factors as at end December 2004 by nuclear reactor vendor. By Richard Knox

The tables of load factors show the averages, maxima and minima, for load factors as indicated, together with other operating and rating data for each of the main reactor types analysed according to the original reactor vendors as covered in our regular review of nuclear power station performance. Where the vendors have changed names, the most recent has been used. Vendors with less than four units in operation are not included (AEG, for example) and reactors are grouped into ‘small’, ‘medium’ and ‘large’ according to gross ratings of less than 600MWe, 600-1000MWe, and 1000MWe and over, respectively. This was done in past years in these pages as a very approximate way of ensuring comparisons of like with like, and for roughly grouping units by age, (although this turns out to be by no means very precise!).

It was also widely believed, in what might be deemed nuclear power’s ‘Golden Age’, that increasing reactor output ratings was having an adverse effect of average performance levels – a case of bigger not being better. Although this was apparently a clear trend some 20 years ago or more, the effect has certainly disappeared now, as can be seen from these tables over the years. If anything, the reverse appears to be true, but this probably does reflect the fact that the lower ratings are predominantly also the oldest units.

The world total in the bottom line of the tables excludes three fast reactors, all of the Ukraine and about four units in China (unavailable), and those units that were produced in total quantities of less than four by any one vendor. As a result, the figures are calculated on 409 of the 427 total units that are included in NEI’s regular quarterly analyses.

The total of 2576.7TWh produced by these 409 units in 2004 increased the average output per unit to 6.3TWh (from 6.1TWh in 2003) and returned to the 2002 level. The total number of reactor years of experience clocked up by individual vendors was headed by Westinghouse (1909.2 reactor years), followed by GE (1388.5) and Framatome (1272.2). No other vendors have got close to achieving four-figure experience in this league (AECL’s 604.3 is the closest). The average annual load factors for these three top vendors were 89.1% for Westinghouse’s 80 units (up from 88.1% in 2003), 82.0% for 52 GE units (up from 81.7% last year), and 76.5% for 65 Framatome reactors (76.7% the previous year). However most of the Framatome units operate in France, where the nuclear proportion of the national installed generating capacity well exceeds the base load, resulting in more extensive load-following than is common for nuclear plant. The highest average annual load factor over all sizes was 90.6% for ten ABB Atom BWRs, only just surpassing the Westinghouse achievement with 80 units.

The level of both the average annual and lifetime load factors is remarkable, and their proximity to each other also reflects an impressive history of reliability that exceeds most other power generation technologies. The world market for new nuclear units has shrunk considerably: the net gain in units in operation was only one in 2004, and indeed is only two for this century to date. The forthcoming planned shutdowns and decommissioning figures will turn this figure sharply negative within a few years. No doubt this turning of the tide will bring sighs of relief from the so-called environmental movements. But watch the carbon emissions soar, and ask which of the world’s leading nuclear plant vendors will have the engineering skills needed for designing new plant capable of repeating the excellence of performance reflected in these figures.


Nuclear reactir performance by vendors: PWRs
Nuclear reactor performance by vendors: BWRs
Nuclear reactor performance by vendors: PHWRs
Nuclear reactor performance by vendors: AGRs
Nuclear reactor performance by vendors: Magnox
Nuclear reactor performance by vendors: RBMKs
Nuclear reactor performance by vendors: All types & vendors
Table of net start ups:
Abbreviations and notes

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