Getting to Know AECL's Principal Scientistby Jeremy Whitlock
A capacity audience gathered last Thursday (January 29) at the J.L. Gray Centre to "Meet AECL's Principal Scientist", as the latest offering of the Canadian Nuclear Society was billed. Dr. Romney Duffey, the guest speaker for the evening, was appointed to the prestigious new post last fall, and the CNS event allowed many to see and hear him for the first time.
The "Principal Scientist" is the research-equivalent of AECL's Chief Engineer, with a mandate to provide both leadership and quality-assurance to the company's long-range R&D program. Accordingly, Dr. Duffey will oversee the so-called "CANDU X" project, which incorporates AECL's evolutionary goals for the CANDU product. He will also assist senior managers in ensuring the high quality and relevance of their R&D programs, and interact with international experts to keep abreast of new technologies.
On Thursday evening, however, Dr. Duffey goal was simply to "get acquainted" with those whose interests (vested or otherwise) he now represents. By way of an introduction, Dr. Duffey began with a spirited slide-show highlighting the career steps leading him to his current posting.
Starting with a PhD in Physics, Dr. Duffey has progressed through a diverse series of research positions, mostly associated with thermalhydraulic and hydrodynamic studies related to nuclear safety. His list of senior positions includes associations with Brookhaven National Laboratory, Idaho National Engineering Laboratory, and the Electric Power Research Institute in the U.S., as well as Berkeley Nuclear Laboratories in the U.K. Dr. Duffey comes to AECL directly from the South Carolina Universities Research and Education Foundation, where he was the Director and Chief Operating Officer.
As well as sharing some of his past research experience, which includes natural circulation in reactor loops, hydrogen detonation shock-wave profiles, and LOCA (loss-of-coolant-accident) experiments in Zircalloy tubes, Dr. Duffey's slide show also emphasized his involvement with both the TMI (1979) and Chernobyl (1986) accident follow-ups.
While visiting Russia as part of a post-Chernobyl workshop, Dr. Duffey was struck by the enormous psycho-social impact that the accident has had on the surrounding population - completely independent of any radiological effect. Today, this poignant memory colours much of his thinking on the future direction that nuclear technology should be taking. Dr. Duffey supports the popular view that evolutionary designs should be safer and simpler (the technical need for this was challenged later by members of the audience).
Assuming that new designs move in this direction, Dr. Duffey sees a bright future for nuclear power. He touched on global warming, atmospheric pollution, and the undeniable link between increasing GDP and electricity usage, to make his case. At the same time, AECL's competitors in the nuclear market are advancing revolutionary designs, and it is his mandate to help ensure that we stay relevant.
In this light, Dr. Duffey introduced the evolution of the CANDU reactor, embodied in the "CANDU X" concept. This design achieves higher thermal efficiencies (40% or greater) through the use of higher temperatures (600 degrees Celsius) and pressures (25 MPa). At these conditions the coolant is termed "supercritical". Since many attractive properties characterize this operating regime, fossil-fuelled plants are also moving in the direction of supercritical coolant. Currently, CANDU thermal efficiency hovers around 30% or less, with 300-degree coolant at 10 MPa.
Other features of CANDU X are: higher passive safety, negative void coefficient, zero plant releases, possibly light-water coolant, and competitive costs compared to natural gas. Once again, many would argue against the technical need for some of these changes, but few question the need for increased competitiveness.
A theme of Dr. Duffey's message was his desire to think "outside the box" in his current posting, and he enjoined his colleagues to speak up if ever his thinking became noticeably "institutionalized". He claims to enjoy free access to anyone in the company, free of the constraints of line management and compartmentalization. As examples of what such thinking produces, Dr. Duffey offered two "observations" for consideration, generating some discussion.
The first was a statistical analysis of airline accidents, linking larger airlines (with more flights per day) with the smallest rate of accidents. Interestingly, this "smallest rate" appears to be a constant lower limit, roughly equal to the average rate of human error.
Secondly, Dr. Duffey used international reactor performance figures, by country, to demonstrate that a slight decrease in average reactor capacity factor is related to an increasing number of reactors operated by a given country. Thus, by this implication, the declining performance of Ontario Hydro's nuclear fleet was inevitable, with the expansion of the fleet itself.
A lively discussion period followed Dr. Duffey's talk. Some questioned AECL's ability to reach the lofty goal of CANDU X, both in terms of financial and human resources - especially since many proposed changes preclude using "off-the-shelf" components. Duffey agreed that it presented a challenge, but one that could be met with a more modest program and a longer timeline.
As already mentioned, others questioned the real (i.e. technical) need for "increased safety", when already the resources spent on marginally improving reactor safety are far out of proportion to the health risk involved. Dr. Duffey acknowledged that the initiative is market-driven, and absolutely necessary.
Finally, there were questions about the scope of Dr. Duffey's mandate, the extent of his "freedom" from institutional barriers, and the degree of consultation (especially with scientists "on the shop floor") that he will encourage. Dr. Duffey appeared confident in his role, encouraged input from all AECL employees (and retirees), and generally exuded the optimism of a scientist embarking on a new quest. He agreed that his ultimate "performance review" will be measured by the health and prosperity of the CANDU product down the road.