www.vtt.fi/nuclear

VTT Technical Research Centre of Finland is an impartial multidisciplinary expert organisation and creates new technologies and innovations by combining knowledge and expertise in different fields. VTT´s main technical focus areas are applied materials, bio and chemistry processes, energy, information and communication technologies, industrial system management, microtechnologies and electronics, and technology in the community. VTT´s turnover in 2007 was 232 M€. VTT is employing about 2,740 persons, out of which about 200 are active in nuclear energy R&D. VTT has a central role in the Finnish national research programmes and coordinates the NPP operational safety research programme (www.vtt.fi/safir2010).

VTT is the major technical support organisation for the Finnish nuclear safety authority STUK as well as for the power companies Fortum and TVO operating the Finnish nuclear power plants and the for the waste management company Posiva. VTT has also broad international co-operation network and has numerous contracts also from foreign utility, industrial and regulatory customers. Recently VTT’s expertise has been employed in the major modernisation projects of the Finnish NPPs and in the systematically proceeding implementation of the nuclear waste management programme.

VTT has been involved in the studies on different types of advanced light water reactors and the Advanced Light Water Reactors (ALWR) research programme of VTT (1998 ‑ 2002) concentrated on safety aspects of the new design features of ALWRs, such as ESBWR, EP1000 and BWR90+. The focus of the work was in those reactors, which could be built in Finland by the year 2010. Thorough understanding of the technical solutions was needed to evaluate the fulfilment of the tight Finnish safety requirements. After the Decision in Principle (DiP) to build the 5th reactor, VTT has acted as the main Technical Support Organisation for the Radiation and Nuclear Safety Authority (STUK). Based on the broad knowledge acquired in the ALWR research programme VTT started with the funding from STUK a comprehensive preparation to the forthcoming independent safety review support to STUK. In this phase the utility TVO was evaluating tenders from different vendors. Therefore in the preparatory phase of the support activities to STUK, several different concepts (EPR 1600, ABWR, SWR-1000, VVER‑1000) were studied in parallel and generic studies were conducted for them to improve the preparedness to perform later detailed analyses for any of the concepts. After the choice of an EPR to be built at the Olkiluoto site, the studies on other concepts were discontinued and all the efforts were concentrated to the evaluation of EPR. During 2003 – 2004 VTT performed a comprehensive set of independent studies on EPR to support STUK in its licensing review of the construction licence application. After the approval of the application, STUK has continued to use VTT’s support in the regulatory control of the construction and main component fabrication works for Olkiluoto 3. In the forthcoming independent studies to support STUK’s review of the operating licence application VTT is going to have a key role again.

VTT has a comprehensive computer code system for safety analyses of LWRs. The system provides tools from basic nuclear data to three-dimensional transient and accident analyses as well as transient fuel behaviour and severe accident studies. The modelling capabilities include also the assessment of environmental impacts and the support tools for off-site emergency preparedness activities. The key codes, three-dimensional reactor dynamics codes and the APROS simulation environment have been developed at VTT, APROS jointly with Fortum Nuclear Services.

Additional information

Rauno Rintamaa Vice President, Business Solutions Tel: +358 20 722 6879 Email: rauno.rintamaa@vtt.fi	Seppo Vuori Customer Manager, Nuclear Energy Tel: +358 20 722 5067 Email: seppo.vuori@vtt.fi
www.vtt.fi/nuclear