Olkiluoto-3 EPR, Finland

In November 2000 Teollisuuden Voima Oy filed an application with the Finnish Government for a decision in principle on a new nuclear power plant unit. In January 2002 the Government made the decision in principle in favour of the new unit. This decision was ratified by the Parliament in May 2002. The project then proceeded to a bidding competition that took over a year. In October 2003 Olkiluoto was selected as the site for the new unit on technical and financial grounds. In December 2003, TVO selected the pressurised water reactor of the consortium formed by Framatome ANP and Siemens from the solutions offered in the bidding competition.

In January 2004 TVO filed an application with the Government for the construction licence of Olkiluoto 3. According to the plans, the actual construction of the unit will start in the spring of 2005. Electricity generation at the new plant will start in 2009.

The new nuclear power plant unit is built at the west end of the island of Olkiluoto, next to plant units Olkiluoto 1 and 2. The total area required for the new unit is about four hectares.

The new power plant unit will utilise the existing infrastructure in Olkiluoto to a maximum extent. The infrastructure is also complemented in many respects.

The new power plant unit will provide permanent employment to 150 - 200 people. During the annual outages, some thousand people will be employed.

According to TVO, the consortium has assigned 700 designers to work on the project. Steam generator manufacturing is proceeding at Framatome ANP's factory in France, manufacturing of the pressure vessel has been started at Mitsubishi Heavy Industries, and the generator rotor has already been cast in Japan. The generator will be manufactured at Siemens' facilities in the US.

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Siemens’ Muelheim an der Ruhr, Germany, engineering center is responsible for architecting design rules and tools used by the company’s worldwide engineering network to design turbines to customer specifications. In the early 1990s, the company moved from traditional 2D parallel-sided blades to 3D airfoil designs as part of a continuing effort to improve turbine efficiency. The change required major modifications to both design and manufacturing processes. The first generation of 3D blade designs were based on conventional quasi-3D blade design concepts addressing the issue that flow conditions vary along the height of the blade, along with the rotational speed. However, amid the development process, engineers recognized that fully optimizing the geometry of the blade would lever further efficiency improvements leading to a novel fully 3D blade design concept. "The use of a model turbine is only partially suitable of exploring these issues," Deckers explains. "One disadvantage is that it is very expensive to build and to instrument. Another issue is that the test results do not provide much information on the detailed flow fields inside the turbine, which are critical in understanding the underlying physics. We needed to get a better understanding of the flow and pressure fields inside the turbine, so we began looking at the various CFD tools in an effort to determine which one would give us the most help."

To achieve high efficiencies at Boxberg, Siemens engineers performed a comprehensive series of parametric simulations using CFX computational fluid dynamics (CFD) software from ANSYS Inc., Canonsburg, PA, in order to derive design rules that are used subsequently to generate optimized blade-path designs based on the pressure, temperature and mass flow rate defined by the customer. They varied the blade airfoils over the height of the blade to better suit local flow conditions, reducing losses associated with secondary flows. The company has also used CFD to reduce losses in the intake and exhaust flow channels. "CFX software played an important role in the development process by allowing us to predict flows and pressures inside the turbine with a minimum amount of model turbine tests", says Mathias Deckers, manager of Steam Turbine Blading Technology for Siemens, Muelheim an der Ruhr. "The CFD software also provides accurate trends in efficiency predictions, making it possible to try a large number of alternatives and pick the one that works best."