Is Small Nuclear Beautiful?

Confidence in large-scale nuclear is ebbing in the United Kingdom. Can small-scale projects rescue this technology, and with it ambitions for a low-carbon economy? Perhaps, but government support, such as that announced this week, is an ambiguous blessing.

The troubles facing nuclear generation, as argued in a previous post, may simply be a feature of its novelty, and a hangover from involvement with the Cold War weapons program. Putting immature technology at the service of a government-driven military objective is, obviously, unlikely to lead to efficient and cost-sensitive engineering, and the obsession with progressively larger reactors, Sizewell B is 1.2 GW, while the proposed Hinkley and Sizewell Cs would be 3.2 GW, is perhaps just a wrong turning, an outcome of the persistent Big Project Syndrome that afflicts state and particularly military projects. The hazards of such schemes are well known.Being necessarily few in number, there is little competition, so errors in technology and over-runs in cost are all but inevitable. Still more to the point, they fail to provide what people in actual fact want or will want, a failing that can be fudged in the case of military matters (the pseudo-finality of Victory is all), but is embarrassingly plain in the case of civil economics.The history of the computer provides a perfect example. While development was still a state and military activity, the industry could only conceive of a future dominated by ever-larger super-computers offering central processing of a narrow band of pre-defined tasks. Once handed over to the neural network of the complete economy, the trend was rapidly in the other direction, towards very small, but powerful desktop and then hand-held devices serving an unforeseeably wide and expanding range of human requirements.That example does not augur well for large scale nuclear. And lest there is any doubt of the overwhelming vastness of the nuclear build contemplated, EdF themselves admit on their Sizewell C website that “Sizewell C would be one of the biggest and most technologically complex construction projects ever built in the UK.” On that sobering ground alone it seems likely to miscarry, either technically or economically.Fortunately, the UK government is showing signs of having recognized that larger may not be better. This week the Department of Energy and Climate Change announced a competition to discover the best Small Modular Reactor (SMR). Such reactors would have an electrical capacity of 300 megawatts or under, less than one tenth of the capacity contemplated at Hinkley and Sizewell.There are numerous advantages. Such plant would be capable of location relatively close to centres of load, cities and would not necessarily require large bodies of water for cooling. Perhaps most importantly they would not add to electricity system costs as the mega-reactors would. The System Operator must have sufficient rapid response generation capacity to take up the slack should the largest generating unit on the system fail whilst online. At present that largest unit is the 1.2 GW Sizewell B. More than doubling it to 3.2 GW will increase the Operator’s requirement for extremely rapid response, and add significantly to consumer costs. Small reactors would not come with the same penalty. Furthermore, the lower capital requirement, shorter construction times and hence lower interest on capital during construction, should make SMR development potentially attractive to private investors, another major point in favour of the technology.However, while the government competition is a good sign in one sense, it remains to be seen whether the announcement will actually help the many international companies and entrepreneurs already interested in this field. One of these potential investors, who asked to remain anonymous, told me that while he appreciated DECC’s gesture, “Unfortunately, the competition will clog up the works at the Office for Nuclear Regulation. (ONR), and delay everyone.”This need not happen, but the Carbon and Capture and Storage competition is hardly encouraging. If it does fail, the casualty list will not be limited to nuclear technology. There is currently no other plausible candidate for a fundamentally economic low carbon energy source. If nuclear fails, the climate change agenda falls with it.