The challenge of deregulation - a supplier's view

The characteristics of nuclear energy use in Sweden and Finland have provided particular challenges for the world-wide active, Scandinavian based ABB concern. These special factors include not only the earlier de-regulation of the energy market and the resulting pressure on costs but also the decision made in Sweden and subsequently Finland to dispense with re-processing and instead to terminally store spent radioactive fuel elements. Furthermore, both of these countries had previously placed value in extension of the life cycles and therefore arranged extensive modernisation programs for older nuclear power stations ranging from repair or replacement of internal components in reactor pressure vessels up to complete replacement of reactor pressure vessels. TVO in Finland has made the greatest progress here, where the thermal efficiency of their nuclear power station Olkiluoto was increased by a further 15 per cent. This meant an actual increase of 25 per cent in comparison with the original performance. In the BWR 90+ which incorporates numerous passive components, ABB Atom had developed a new evolutionary reactor type. The modernisation, partly due to requirements of the supervisory bodies, included renewal of instrumentation and monitoring equipment and their conversion to a digital basis. The type-SVEA 10x10 fuel elements developed by ABB Atom were first installed in 1981 in block 1 in Ringhals. Characteristically they have particularly low leakage rates and use the element Gd for neutron absorption. Meanwhile around 1700 such fuel elements have achieved burn-up rates of 40 MW d/kgU and more. Recently burn-up rates averaging as high as 45 MW d/kgU are being achieved. Although this is lower than in nuclear power stations that have opted for re-processing, the considerably lower disposal costs for direct terminal storage must also be considered. (orig.)