Hindsight is 20-20, how good is foresight?

The physicist Neils Bohr once said: "Prediction is very difficult, especially if it's about the future." Despite these wise words, executives in the nuclear power industry have to plan for the future of their companies, often looking some distance into the future to develop designs that are going to be in demand when they come to fruition.

In the June 1986 issue of Nuclear Engineering International (NEI), we asked six senior executives from some of the major vendors a series of seven questions.

How well did the experts do in their predictions? It is only fair to mention that the predictions were made just before the Chernobyl disaster, and the negative impact that it had on the nuclear industry. The predictions also pre-date the Kyoto talks, the dissolution of the Soviet Union, the growth in perception of terrorist atrocities, and the global financial crisis of 2008. So the experts have had to predict across some very turbulent years.

One of the questions asked by NEI related to the future of small reactors. The question was: "Is there really any commercial future for reactors of less than 600MWe in either developing or the industrialised countries?"

The six experts questioned were:

• James Donnelly, AECL.
• Lars Torseke, Asea Atom.
• Jean Claude Leny, Framatome.
• Shelby T. Brewer, Combustion Engineering.
• James Moore, Westinghouse.
• George A. Roupe, General Electric.

How did the experts respond to this question? They didn't agree, and their responses ranged from optimism that there is a significant energy market to pessimism resulting from the ability of large plants to operate below capacity if required.

While there has been a lot of interest in the concept of SMRs, with many detailed designs produced, the last 30 years have not seen large numbers begin operations. Designs such as the PBMR have promised much, and have had many innovative ideas. But conversion to commercial, operating reality has proved elusive.

The IAEA conducted an assessment in 2009, and concluded that there could be 96 SMRs in operation around the world by 2030 in its high case, and 43 units in the low case.

What did the experts agree on?

The experts generally agreed on the need to get the economics right. They agreed that the relatively low investment cost of SMRs compared to larger nuclear plants made SMRs attractive in markets where the electrical grid size does not justify large plant sizes, and where large financing is an issue. Shelby T. Brewer pointed out that "serial installation of smaller units can better match uncertain load growth and abate financial risks."

Lars Torseke said: "A number of consecutive small units instead of a single large one also provides better possibilities of keeping continuity in industry and competence alive."

The experts did agree that any demand for SMRs was likely to be based in developing countries, although there was disagreement of whether there would be much demand from industrialised countries. Levy said: "There is a need for reactors of less than 600MW in developing countries and to meet special conditions in industrialised countries such as remote or sparsely populated areas," distinguishing between the market conditions in developing and industrialised countries.

What did they disagree over?

However, several of the experts commented that the smaller size of SMRs removes the advantages of scale, which was the basis
for increasing reactor sizes to build 900MW and 1,500MW plants. Jean Claude Levy said: "It is not always obvious that these plants [SMRs] can compete with conventional fossil fuel-fired stations."

James Moore raised a point with regard to larger units operating at a derated power level. He said: "A 600MW plant can be operated initially at a derated power level on smaller electrical grids and progressively increased in power as electrical demand increases. For utilities with demand growth rates of 5-10% per year, this mode of operation can result in generation costs that are competitive with fossil fuel power plants down to initial power levels as low as 300MW."

The experts didn't agree on the size of SMR for which there would be the largest demand. James Donnelly said studies undertaken by AECL suggested that there was a significant market for units in the 300-400MW range, while George A. Roupe said: "The potential use of modular-type reactor designs in unit sizes of about 100MW may be able to meet some of these future small plant size applications."

Brewer said the big disincentive to construction of SMRs was the difficulty in making them economically viable. He said: "Given the limited number of reactor sites and fixed costs that are not size related, larger nuclear units shared by several utilities make economic sense wherever the grid size can take a larger unit."

Roupe, Donnelly, and Torseke all mention that a small or weak transmission network favours SMR construction.

What they didn't say?

There were a number of issues that the experts failed to mention, presumably because at the time, the issue was not felt to be important.

None of the experts mentioned the possible impact environmental considerations might have on SMR build. The phrase global warming first entered the public arena in 1975, and was starting to gain traction by 1986. It was still something of a fringe view, but while all of the experts talk about the economics of SMRs, none mentioned CO2 emissions as a factor.

All of the experts failed to mention the possible role of very small units, such as the 10MW U-battery under design by Urenco. This is not a big surprise, given that so few have gone beyond the conceptual design phase. Urenco has called for European development of the U-battery, which it describes as an inherently safe plug-and-play reactor based on graphite-moderated HTR concepts.

And finally, given that in 1986, mobile phones weighed around 1kg, and cost around $2,500 in the US, it is no surprise that none of the experts mentioned the communications and information technology revolution.