The nuclear renaissance – technologies and challenges
It is rare that we all seem to agree on any- “double jeopardy” – whereby a plant can thing these days, but one thing few people be built but still not be allowed to operate disagree with is that global demand for en- – are prohibitive barriers to potential in- ergy in general – and electricity in partic- ular – is set to rise steadily over the com- This trend poses some difficult challenges Long-term electricity contracting: No as policy makers are tasked to deliver elec- baseload stations have been built in a fully tricity supply systems in ways which meet Director of Technology and Operations
is a particular issue for nuclear, with long affordably whilst allowing significant im- is responsible for BNFL Group’s investment in lead times and the relatively high capital cost of generating units. Renewable plant She is a recognized world expert on nuclear fuel and was the 1993 winner of the UK’s Hinton operators can secure 20-year contracts at Policy to deliver this balance is set at the Medal for outstanding contribution in nuclear premium prices – if similar contracts were engineering. A fellow of the Royal Academy of available to nuclear utilities, the reduced Engineering, the Institute of Materials and the Institute of Nuclear Engineers, she is also a mem- investor uncertainty would make nuclear a ber of various international/national bodies including the IAEA’s Standing Advisory Group on Radioactive waste policy: On UK ra- the generic issues discussed above, indi- is the past, but there is no doubt it has left For instance, in the UK over 70% of elec- tricity is set to come from a single fuel source (gas) by 2020, as traditional coal • Nuclear is the only large-scale source of reliable low-carbon electricity.
is shut down. The predicted decline of nu- clear’s share is a concern to many opinion- placing the UK’s entire nuclear fleet with not technical, as will be discussed later.
• Finally, nuclear is affordable. With the
around 10% over their lifetime to the vol- • Nuclear power in the UK and worldwide has an impressive safety record. In spite
could easily turn out to be cheaper.
So why is the world not awash with appli- However elsewhere challenges remain.
• Prolonged safe storage is a viable ap- hibit “passive safety”, for example the Again it is helpful to focus on the UK sit- There are five main areas where obstacles exist – all of them connected with policy • Future nuclear generators need clarity • Nuclear makes a positive contribution and regulation, rather than technology or in respect of their obligations for spent to overall reliability and security of
Climate change mechanisms: Current Skills and training: There is also a need to sity within the overall portfolio of sup- ensure the maintenance of the skill base.
generation (and large hydro plant) by fail- The depth of skills in some critical areas ing to recognize their environmental con- for new reactor design, licensing and con- tribution. A level playing field is needed and such skills cannot be re-created over a ation and it is credible to retain strate- Planning and regulatory approvals: Nuclear Europe Worldscan / Spring 2002 Edition needed, as is participation in international R&D collaborations on next-generation The Pebble Bed Modular Reactor
The key was to simplify rather than further Like the AP series, the PBMR is not a new complicate the design in the drive for im- concept. The design benefits from the ma- special pleading for nuclear – instead they liant on passive rather than active safety viding incentives in a competitive market place, targeted at delivery of the stated the major systems, factory build and much enhanced constructability were called for • Competitive generating costs relative signs and technology, it is important to re- alize that as well as delivering safe sys- tems, the industry will need to deliver eco- the first pouring of concrete to fuel load- • Low projected capital cost per module, • High degree of utility flexibility, for use risk to investors. Paradigm shifts in ap- lowest-cost nuclear option, it was felt that proach and avoidance of past mistakes are essential. Principally, the industry must be • Short construction time – the target is disciplined enough to resist “one-off ” de- signs. A series of near-identical units is technology, fed by gas at prices lower than • Inherent safety characteristics elimi- nate accidents with potential for off-site economies of replication – probably on an the development of the AP1000 – the big- Yet in today’s global marketplace require- over 80% of the original design basis.
• Irradiated fuel is very stable – well ments do differ considerably, impacted by By delivering safety through the inherent tion of achieving licensed status in 2003 or characteristics of the plant, rather than ‘big is beautiful’– with economies of scale through dedicated systems – whether they through bigger and bigger units – is no are active or passive – significant eco- be achievable because the costs of expen- overnight capital costs down, to introduce concrete and cable are all well known. The short construction period are of particular safety and to yield better generation eco- kilometers of pipe, cables and so on in ex- module is much easier to swallow as an in- isting plants are recorded. The bill of ma- To illustrate the way reactor vendors have terials for the AP600 and AP1000 calls for responded to these challenges, it is useful difference, in terms of reduced capital out- lay, is also clear. The industry can there- tractive in the longer term. BNFL’s in- fore be confident in claims that projected projects like Dragon and the solid techni- yield generating costs in the range 2.2 – cal base in gas-cooled systems generally.
and a 60-year operating lifetime can con- leading to a demonstration plant to be built The Advanced Passive (AP) series
nents and systems routinely called upon to the technologies necessary to meet the needs sive (AP) platform builds on proven, well- of nuclear utility customers in the short term and in the future. If the political, policy and improved over the past one or two decades.
regulatory frameworks can be rectified to The goal of the AP project was to meet the with large systems is likely to be evolu- utility challenge to deliver a unit of 600 where this is not already the case, then the MW (set as an initial target in the US) and smaller, typically 100 – 300 MW, concepts industry will be able to play its key role in is to deliver excellent and reliable eco- achieving the elusive “win-win” outcome to plants operating at the time. A decade of Nuclear Europe Worldscan / Spring 2002 Edition

Source: http://tts.lt/~sirand/ens/pdf/feature_Ion.pdf

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