July-August 2018 NPJ

22 NuclearPlantJournal.com Nuclear Plant Journal, July-August 2018 Passively Safe Plant By Luca Oriani, Westinghouse Electric Company LLC. Luca Oriani As the Vice President for Plant Engineering and Licensing for Westinghouse Electric Company, Dr. Luca Oriani has operational responsibility for design engineering for Westinghouse plants. This includes oversight of the design and engineering for all ongoing AP1000® projects in China and the U.S., as well as design authority responsibility for the AP1000 nuclear power plant. Dr. Oriani has grown through various leadership roles during his 17 years of experience with Westinghouse, where he began as a design engineer for the research and development of new plants. He has worked on the development and international licensing of advanced nuclear safety analysis methods, and led the design efforts for fluid systems and piping for the AP1000 plant prior to his current role. Dr. Oriani holds a patent and has had more than 40 technical papers published on the topics of nuclear passive plants and safety analyses. He is a certified Customer 1st Leader and a black belt in Design for Six Sigma and Lean processes. Dr. Oriani holds a doctorate degree in nuclear engineering from the Polytechnic Institute of Milan, Italy. A telephone interview by Newal Agnihotri, Editor of Nuclear Plant Journal. 1. What makes the AP1000 a special design? We started development of the AP1000® nuclear power plant in the ‘80s, well before I was working: decades of Westinghouse nuclear technology de- velopment were the basis for the design. When you look at the current generations of nuclear power plants, they are robust, safe and reliable technologies. They de- liver safe and clean electricity with mini- mal impacts on the environment. The AP1000 plant rep- resents a significant additional step in the evolution of civil nuclear technology. The key feature of the AP1000 plant is the replacement of complex redundant safety systems that are powered with AC power with pas- sive safety methods such as gravity and heat transfer by con- duction, convection and radiation. One of the fundamental aspects of the current generation of nuclear power plants is that they rely on AC electric power to bring the plant to a safe state and remove de- cay heat. When we designed the AP1000 plant, we wanted to develop a solution that would not only simplify the plant but also provide a design that considers the capability to mitigate potentially cata- strophic environmental events, (seismic, hurricanes, tsunamis, etc.,) within that simpler, and more robust, design. The concept that we focused on developing is the approach that the AP1000 plant embodies. The AP1000 plant does not re- quire AC electric power to achieve safe shutdown nor to establish and maintain, for an extended period of time, safe shut- down mode while removing decay heat from the nuclear fuel. By removing the reliance on AC power, you solve the para- dox in which you need AC power to re- move decay heat. With the AP1000 plant design, you don’t need AC power. You just need the laws of physics and stored energy from DC batteries, compressed gases and gravity to remove decay heat, and that is what achieves the simplicity and robustness. Additionally, the AP1000 plant has been designed since its inception to operate for 60 plus years. It is also designed to be more adaptable to modern grids, with a variety of different electricity generation sources. For example, the AP1000 plant is designed to remain operating after a 100 percent grid load rejection – supporting the grid by rapidly providing power to the grid once the fault is cleared. The current fleet of nuclear power plants would trip due to grid malfunctions and would not be able to provide grid support for several hours after the event. 2. Please describe the application of data analytics to AP1000. In general, data analytics have been a field of development for the entire nuclear industry. It is something that Westinghouse has invested in and has been at the forefront of, in a number of different aspects. Specifically, we have developed tools to analyze component data, such as pumps, motors, heat exchangers, and so forth, to allow the optimization of maintenance activities. I think the key aspect of the AP1000 plant in relation to data analytics is that we were designing the AP1000 plant’s instrumentation and control system and the plant infrastructure in parallel to the maturation of data analytics in operating nuclear plants. The main advantage that the AP1000 plant has compared to operating plants is that, for much of the operating fleet, there are challenges with acquiring additional component data to perform the necessary analytics. We were able to develop the AP1000 plant data analytics within the plant instrumentation and control system and in the plant infrastructure. We were able to take advantage of modern information technology to ensure we have the embedded capabilities to collect extensive data, which can then be utilized in modern data analytics. Another key aspect is that the plant design integrates the data into the plant 3D model. The plant information and control system technology enables an Gen III+ Nuclear Power