ITER Participation and Possible Fusion Energy Development Path of Korea

Transcription

1 1 ITER Participation and Possible Fusion Energy Development Path of Korea C. S. Kim, S. Cho, D. I. Choi ITER Korea TFT, 52 Eoeun-dong, Yuseong-gu, Daejeon , Korea The objective of this paper is to explore Korean plan of fusion energy R&D and technological innovations which is very likely to make fusion technology a promising power source for future national developments. In other words, this aims at a long-term strategic planning of fusion energy R&D and technological innovation in order to promote the socio-economic contributions of science and technology for the nation's future competitiveness and sustainable development and to contribute to develop the global energy security and clean environments. Korean fusion research activities up to now including ITER participation will be described, and we would like to emphasize the importance of ITER. Then, the future needs of fusion energy would be predicted briefly, and we will provide the possible Korean fusion energy development path. We are aiming at the operation of a demonstration fusion power plant in To achieve this goal, the efficiency of Korean fusion energy R&D and technological investment should be promoted by centralizing our whole activities. Assuming the hurdles ahead of us, possible fusion energy development plan of Korea should be arranged by taking into account the international cooperation. 1. Introduction There is a quite long history on the fusion research program in Korea. SNUT-79, KAIST Tokamak, KT-1, HANBIT, KSTAR(in construction) were the major steps in our history. Now Korea is participating in ITER project in collaboration with China, Europe, Japan, Russia and the United States. ITER is the indispensable experimental step between today s studies of plasma physics and tomorrow's electricity-producing fusion power plants. More and more interests and activities would be put on this program, and we hope that Korea would be the major player to develop the fusion energy for human beings. 2. Korean Energy Program Korea has lack of domestic natural resources. 97% of energy is imported, and 80% of energy import is crude oil from Middle East. Anticipated average annual growth rate of energy demand through 2035 is 2.3%. Korea has rapid increase of electricity demand. About 7 times in 20 years from 1980 to 1999 with an average annual growth rate of 10.3%. Anticipated average annual growth rate of electricity demand through 2015 is 4.9%. Korean total CO 2 emission amount ranks 10th in the world. Emission per unit area is the highest in the world.

2 2 Export expected to lose price competitiveness due to CO 2 Tax. We need to prepare future social demand for the unification of Korea. First commercial nuclear power plant Kori Unit 1 started operation in Currently there are 16 PWRs and 4 CANDUs in operation. 8 out of 16 PWRs are KSNP (Korea Standard Nuclear Plant), 6 in preparation, and total 28 units planned by Nuclear power shared, as of Dec. 2003, 28% of total installed capacity (6th in the world) and 40% of total electricity generation. Korea has a substantial infrastructure on nuclear technology, shares the key technologies with fusion reactor, design of various fission reactors, experiences with tritium recovery and storage from CANDUs, relatively young and experienced staffs. 3. Korean Fusion Research Program SNUT-79 and KAIST Tokamaks Korea has been involved in plasma and fusion research in a modest way since the mid-1970s. Most activities were small in scale and housed within various universities. Based on basic plasma and fusion researches at Universities in 1970 s, Seoul National University developed a small scale fusion research device named SNUT-79. And, KAIST (Korea Advanced Institute for Science and Technology) developed another device named KAIST Tokamak. These programs have valuable meanings to launch real tokamak projects in Korea, and to develop human resources in Korean fusion program up to now. Fig. 1. SNUT-79 Tokamak. Fig. 2. KAIST Tokamak. KT-1 and HANBIT In the mean time, KAERI (Korea Atomic Energy Research Institute) developed KT-1 tokamak in a research institutional territory. In 1995, the Korea Basic Science Institute installed a medium-sized device called HANBIT, which is now fully operational. HANBIT is

3 3 devoted to basic plasma research such as basic plasma diagnostics and radio frequency/microwave heating method development. It is operating as a national-user facility and drawing more than 20 research work groups from universities and research institutes throughout the nation. Fig. 3. KT-1 Tokamak in KAERI. Fig. 4. HANBIT Tandem Mirror in KBSI. Within the Korean Physical Society, the plasma physics division was formed in 1982 and has grown steadily, with over 300 members today and numerous activities from low-temperature plasmas to high-temperature fusion plasmas. Other related societies are the Korea Accelerator and Plasma Research Association (KAPRA), the plasma division of the Korean Vacuum Society, IEEE of Korea, and the Korean Nuclear Society. Along with an active accelerator program centered at Pohang Accelerator Laboratory (PAL), these societies are covering a vast range of plasma applications activities from plasma-assisted semiconductor fabrication to plasma waste disposal. Industrial and academic sites are closely involved with this community by exchanging materials and research personnel. Membership in the community and overall funding support from industrial sites is growing rapidly every year. KSTAR KSTAR stands for Korea Superconducting Tokamak Advanced Research. The mission of the KSTAR project is to develop a steady-state-capable advanced superconducting tokamak [1,2]. To support this project mission, the three major research objectives have been established: (i) to extend present stability and performance boundaries of tokamak operation through active control of profiles and transport; (ii) to explore methods to achieve steady state operation for tokamak fusion reactors using non-inductive current drive; and (iii) to integrate optimized plasma performance and continuous operation as a step toward an attractive tokamak fusion reactor. By KSTAR project, we can approach to construct and handle medium size superconducting tokamak.

4 4 Fig. 5. KSTAR Tokamak in KBSI. 4. ITER Participation Korean ITER participation impacts huge things on her fusion research as an energy development program. As you know, Korea has no major oil field at all up to now. So, we are much interested in developing future energy source with the other parties. ITER is the indispensable experimental step between today s studies of plasma physics and tomorrow's electricity-producing fusion power plants. Up to now, the fusion research program is not an energy development program, but it changed with ITER participation. And, we have a substantial infrastructure to join ITER and the fusion energy development. Furthermore, Korea has very active nuclear society which shares technologies with fusion society. Anyway, we have good reason to participate ITER and fusion energy development program. This is the Mid-Entry for Korea. Korean ITER participation makes a really big progress in Korean fusion program now. We concluded that ITER is the indispensable experimental step between today s studies of plasma physics and tomorrow's electricity-producing fusion power plants. So, we are going to launch not just Korean ITER participation program but also the fusion energy development program in good collaboration with the other partners. 5. Tritium Supply Consideration Right now, only Canada can supply large amount of civilian tritium, and around or over 20 kg

5 5 is available from Canada. For the fusion energy production of 1000 MW including alpha heat for a year, we need 55.8 kg of tritium. This is a huge amount of tritium considering the available tritium in our hands now. Furthermore, fusion has never bred tritium up to now. ITER startup tritium inventory is estimated to be around 3 kg, and the DEMO startup tritium inventory is likely to be between 4-10 kg. Fig. 6 shows the worldwide tritium inventories without fusion, with ITER-FEAT and with 1000 MW fusion by 10% availability and no tritium breeding. [3] Availability of external tritium supply for continued fusion development beyond ITER first phase is an issue. Large power D-T facilities must breed their own tritium. This is why ITER s extended phase was planned to include the installation of a tritium breeding blanket. Blanket development and ITER-TBM are necessary in the near term to allow continued development of D-T fusion. Wolsong Tritium Removal Facility (WTRF) is now under construction to remove the tritium from heavy water at CANDU reactors in Korea. That means that more than 10 kg of tritium from Korea is available additionally. [4] WTRF will start its operation at the end of this year. Additional Korean tritium supply can be a marginal source to the startup inventories and the consumption in ITER and DEMO. Korea is to deliver the tritium storage and delivery system to ITER and this can be very good opportunity to take advantage of Korean tritium supply. The achievable tritium breeding ratio should be somewhat larger than the required tritium breeding ratio. The achievable tritium breeding ratio is a function of technology, material and physics. Most of our works on Korean fusion energy development path should be focused on increasing the achievable tritium breeding ratio by the developments of technology, material and physics. The required tritium breeding ratio is 1+G, where G is the margin required to account for tritium losses, radioactive decay, tritium inventory in plant components, and supply inventory for start-up of other plants. Physics and technology R&D needs to assess the potential for achieving Tritium Self-Sufficiency. So, we are going to establish the conditions governing the scientific feasibility of the D-T cycle, i.e., determine the phase-space of plasma, nuclear, material, and technological conditions in which tritium self-sufficiency can be attained. And, we need to develop and test FW/Blankets/PFC that can operate in the integrated fusion environment under reactor-relevant conditions. The ITER Test Blanket Module (TBM) is essential for experimental verification of several principles necessary for assessing tritium self-sufficiency. R&D on FW/Blanket/PFC and Tritium Processing Systems should be done by minimizing Tritium inventory in components, much faster tritium processing system, particularly processing of the plasma exhaust, and improving reliability of tritium-producing (blanket) and tritium processing systems. The R&D on physics concepts should be added to improve the tritium fractional burn-up in the plasma.

6 6 Fig. 6. World Tritium Supply Would be Exhausted by 2025, if ITER were to Run at 1000 MW at 10% Availability. [3] 6. Korean Fusion Energy Development Path We can set up our fusion energy development path as Fig. 7, which will be approved by Korean Science and Technology Council in months. Based on the Korean fusion energy development path, we are going to launch various activities on ITER test blanket, tritium fuel cycle including breeding blanket, fusion material, safety assurance, DEMO and power plant studies, hydrogen production, etc. The world needs major sources of environmentally responsible energy, and fusion is one of very few options. By Korean Fusion Power Plant Studies, it is time to move to a project oriented approach through fast track with DEMO and following KFPP. This will require a change in mind set, organisation and funding. First steps are for fusion community to agree an guiding fast track model and for government to fund to turn aspirations to reality Korean Fusion Power Plant Study should be launched soon. Korea has a substantial nuclear infrastructure which shares technologies with nuclear fusion. Korea would be serious about the development of the fusion energy. The information accumulated in and out of Korea is being investigated. Systems code varies the parameters of the possible designs, subject to assigned plasma physics and technology rules and limits, to produce economic optimum. Plasma physics, cost, material, maintenance and safety concern. The outputs are to keep the cost of electricity lower,

7 7 to keep safety and environmental features excellent with external costs to health and environment of those of wind power, and to make economically acceptable fusion power stations, with major safety and environmental advantages. It seems to be accessible on a fast-track through ITER and material testing by IFMIF, even without major material advances. Fig. 7. Korean Fusion Energy Development Path. DEMO is regarded as the last step before commercial fusion reactor. The requirements of DEMO is to demonstrate a net electric power generation, to demonstrate a tritium self sufficiency, to have a reasonably high thermal efficiency to show an extraction of high-grade heat and positive evidence of a low COE, to demonstrate the safety aspect of a power plant and to be licensable as a power plant. With limited extension of the expected plasma physics and technology from the 2nd phase of the ITER operation, major technical parameters can be derived. Those are the fusion power of about 2 GW for a net electricity generation, neutron wall loading of above 2.0 MW/m 2, maximum FW heat flux of less than 1.0 MW/m 2, low-activation structural material usage and thermal efficiency of above 30%. Based on the DEMO concept, Korean ITER Test Blanket Module concepts are solid and liquid breeders. The sold breeder features technically mature and all 6 parties have interests. Conceptual design of HCSB with graphic reflector is underway. Small size sub-module will

8 8 be tested from a day-one operation of ITER and independent TBM will be tested from a later phase (D-T phase) of the ITER operation. For the liquid breeder concept, conceptual design of He-cooled Li-breeder/FS (HCML) is underway. HCML TBM will be tested from a day-one operation of the ITER. And we are also interests in the R&D progresses of other TBM families, and we will contribute to the development of TBMs through collaboration. Blanket concept as well as the DEMO concept needs to be updated based on the R&D achievements We may propose International Center for Energy Research in Korea later. That may contain Proto/DEMO Fusion Reactor in Unified Korea! This is another fusion program in Korea. References [1] D.I. Choi, et al., The KSTAR tokamak, Proceedings of the 17th IEEE:NPSS Symposium on Fusion Engineering, vol. 1, 1997, pp [2] W. Reiersen, et al., The design of the Korea superconducting tokamak advanced research (KSTAR), Proceedings of the 17th IEEE:NPSS Symposium on Fusion Engineering, vol. 2, 1997, pp [3] M. Abdou, Fusion Nuclear Technology, presented at ISFNT-7, Tokyo, May 25, [4] C.S. Kim, et al., WTRF Tritium Production and Fusion Consumption, presented at Tritium 2004, Baden-Baden, Germany, September 14, 2004.