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Overview of Nuclear Power Development in China
Tong Jiejuan Sun Yuliang
Institute of Nuclear and New Energy Technology
Tsinghua University, Beijing 100084, PR China


1. Energy and power economy
Continuous rapid economy growth in China has been taking place in the past years, along with the remarkable increase in primary energy and power consumption (Figure 1). According to the latest statistics[1] , the annual primary energy consumption in China reaches 2613 Mtoe in 2011 with an average annual increase of 9.02% over the period of 2000-2011. Electricity generation and consumption experienced even more vigorous growths in the past decade.

Figure 1 Primary Energy Consumption and Electricity Generation (2000-2011)

In order to catch up with the social-economic development, China has taken a series of reformatory measures in the energy industry. Energy supply capability has been improved significantly. For example, the installed electricity generating capacity in China has been developed with an average annual increase of 9.2% and reached 1056 GW in 2011[2] (Figure 2).
According to the general social-economic development goals which Chinese government has set for the next decades[3], the per capita GDP by 2020 will quadruple relative to that in 2000, and by the middle of this century, the per capita GDP value will increase from the current value of about 3,000USD to 25,000USD, about the level of some moderately developed countries. Therefore, it is expected that primary energy and electricity consumption in China will continue to grow significantly in the next decades.


Figure 2 Electricity Generation Capacities (2000-2011)
Besides the challenges brought by the economic development demand, the challenges from the energy restructure are notable either. One of the most striking characteristics of China’s energy economy is its heavy reliance on coal (Figure 3)[1], which takes up about 70% in primary energy consumption. Hydropower contributes to 17.67%, and the rest is contributed by oil, gas, nuclear and some renewables. This coal-dominant energy structure leads to huge pressures in terms of environmental protection and carbon dioxide emission reduction.


Figure 3 Primary Energy by fuel in 2011

These boundary conditions set by the social-economic growth and clean energy policies make the energy economy development in China rather challenging. The following two aspects would be of special significance in the mid- and long-term energy development strategies in China:
Promotion of energy saving and overall control of total energy consumption.
 Acceleration of energy economy restructuring towards a low-carbon energy economy. The share of non-fossil energy forms is expected to reach 15% by 2020 and over 30% by 2050.

What roles should nuclear power play in the future? Before Fukushima, very few people questioned about the important role of nuclear energy. Fukushima crisis then has led to some discussions and debating. It is believed that China will resume its nuclear power development program based on enhancing nuclear safety.

2. Past development and current status of nuclear power
China’s civil nuclear power development started in 1970’s. The first nuclear power plants were built in 1980’s and put into operation early 1990’s. But the pace of nuclear power development had not been particularly fast until several years ago when China’s government shifted its nuclear power policy from “moderate” to “active” development. In 2006 China’s central government approved the plan for nuclear power development until 2020, which sets up the framework for introducing and constructing Generation III advanced water cooled reactors and for constructing moderate numbers of improved Generation II nuclear power plants. That plan foresees 40GW of nuclear power to be constructed and some 18GW under construction by 2020. Under that framework, nuclear power construction has been very much active. Currently there are 15 nuclear power reactors under operation, having a total generating capacity of 12.6GW. 26 units are under construction with a total capacity of about 29.4GW. Most of these units are improved Generation II reactors, except for 4 AP1000 units and 2 EPR units. Besides, there are still around 20 nuclear reactor units under planning with the total estimated capacity of 20GW.

The nuclear power plants under operation and construction in China have already incorporated a lot of technical and safety improvement and experience feedback since the Three Mile Island and Chernobyl nuclear accidents. And Chinese nuclear power plants have got excellent operation records over the past years[4]. According to WANO operational performance statistics, Chinese nuclear units are generally at high international levels. The average load capacity factor over the five years is 85.7%. Some units are at advanced levels and even top ranking.

There are also advanced nuclear power technology development programs. These programs include the development of advanced light water reactor technology, sodium cooled fast reactor technology, high temperature gas cooled reactor technology and some other even more advanced technologies such as accelerator driven systems or molten salt reactors. On 21st of July 2011, the China Experimental Fast Reactor, having a thermal power of 65MW and electric output of 20MW, was constructed and successfully put into power operation. The first industrial scale demonstration nuclear power plant of high temperature gas cooled reactor with the pebble bed design (HTR-PM) is being projected in Shandong province. The project has been part of the national mid- and long-term science and technology program till 2020 which requires that by 2020 the HTR-PM demonstration plant be finished and a good industrial basis be established for future applications.
As the indispensable part of the nuclear energy development, the Chinese nuclear safety regulatory authority was established in 1980’s. Good regulatory experience and practices in the world have been studied and reflected into the regulatory system in China. In particular, the nuclear safety standards have been derived mostly from IAEA standards series which have absorbed worldwide experience in nuclear safety.
3. Actions after Fukushima and future outlook
The Fukushima accident has resulted in profound impact on nuclear power programs in many countries in the world including China. Right after the outbreak of the Fukushima nuclear accident, the central government of China made, on the 16th of March 2011, several decisions in order to check and assure nuclear safety of the Chinese nuclear power programs. The decisions require immediate nuclear safety inspections and examinations of all nuclear power plants under operation and construction against most strict regulations, enhancement of safety management at operating nuclear units, enhancement of national nuclear safety programs, and adjustment and optimization of nuclear power development programs.
3.1 Nuclear safety inspections and examinations after Fukushima
The nuclear safety inspections and examinations lasted for 9 months in 2011 extensively, and were carried out to all the units under operation and construction. The inspection aspects covered include validation of external events used for siting evaluation, anti-flooding procedures and the actual capability evaluation, seismic design and seismic margin evaluation, prevention and mitigation measures in case of concurrence of multiple extreme natural events, evaluation and contingency guideline for station blackout, severe accident prevention and mitigation measures as well as the corresponding reliability evaluation, effectiveness of environmental monitoring and emergency response frameworks and so on.
The above mentioned inspections and examinations were implemented by several ways such as self-examination, expert walk-down, document inquiry and review, etc. The final findings and conclusions were approved for release formally by the State Council in June 2012. In order to increase the public acceptance and involvement, full text of the inspection report is published for public comments. The following conclusions are stated in the report.
Nuclear industry in China has certain advantages of “later start”, benefiting from the international good experiences in design, construction and operation, and nuclear safety has been always regarded as the essential principle of the nuclear industry. Since it was founded in 1984, National Nuclear Safety Authority (NNSA) of China has set up the complete set of nuclear safety regulations and standards, which are closely connected with the international level. NNSA has fulfilled the independent inspection and review successfully. Chinese nuclear units have got excellent operation records, e.g. no operational events are serious than INES level 2. Generally speaking, all the operating nuclear units meet the existing nuclear safety regulations of China and the latest IAEA standards, having sufficient capability to deal with the design basis accidents and having certain capability for severe accident prevention and mitigation. Hence, the risks are under control and the safety of these nuclear units continuing operation can be assured.
With respect to the units under construction, the series of self-designed units are of higher safety over the similar units in the world, because the technologies adopted are the integration of continuous upgrade and optimization over the 30 years, based on the introduced international mature technology. Besides, AP1000 and EPR are the representatives of the new advanced nuclear units in the world. They have had sufficient considerations on severe accident prevention and mitigation from the design stage, the design safety levels have been improved further. In general, all the nuclear power plants under construction meet the existing nuclear safety regulations of China and the latest IAEA standards. Effective management has been implemented to the processes of siting, design, manufacture, construction, installation and testing. Quality assurance procedures are working as normal; the engineering construction meets the design requirements. Hence, overall construction quality is under control.
All the civil nuclear facilities have undergone sufficient investigations about the earthquake and flooding occurrence. It is very rare that the extreme nature event like Fukushima nuclear accident can occur in China”
The report also identifies potentially vulnerable aspects and gives recommendations for modification actions in order to promote even higher safety of Chinese nuclear power plants.
 Recommended modification action No. 1: To meet with the functional requirements of reactor core cooling, spent fuel pool cooling as well as necessary post-accident monitoring capabilities given the situation of station blackout like Fukushima, measures such as providing portable power supply, portable pumps and the matched interface devices shall be taken.
 Recommended modification action No. 2: Recent researches and evaluations about the Fukushima shall be traced closely. Nuclear power plants shall refine the severe accident management guidelines, evaluate and improve the availabilities and reliabilities of the devices and systems used for severe accident mitigation. The possibility of hydrogen explosion shall be evaluated and mitigation devices shall be modified if necessary.
 Recommended modification action No. 3: Anti-flooding capabilities of doors, windows, ventilations and penetrations shall be examined one by one in case of beyond design basis flooding. Blocking and sealing measures shall be taken if necessary.
 Recommended modification action No. 4: Qinshan nuclear power plant is required to perform the specific modification action against flooding by dam height extension, anti-wave wall setup, water proof and drain measures implementation and so on. Before the modification action finishes, if there would be a high tide together with typhoon condition, the reactor shall be set back to the cold shutdown mode.
 Recommended modification action No. 5: All the nuclear power plants shall start the external event probabilistic safety assessment (PSA), including seismic PSA and seismic margin analysis; Daya Bay nuclear power plant has the specific requirement to carry out the seismic-tsunami risk analysis and take the necessary modification actions.


 Recommended modification action No. 6: All the nuclear power plants shall enhance the maintenance and management of seismic monitoring and recording instruments and devices to ensure the effectiveness of monitoring system; Operator actions after the earthquake shall be improved to increase the plant seismic emergency response capability.
 Recommended modification action No. 7: All the nuclear power plants shall improve the environment monitoring capability and emergency control center functions under severe accidents; Response guidelines shall be defined to deal with multiple units in the site entering the emergency state simultaneously; Emergency control capability and coordination and distribution solutions of human and material resources shall be evaluated.
 Recommended modification action No. 8: Cooperation companies such as CNNC and China Guangdong Nuclear Power Cooperation (CGNPC) shall improve the emergency response capabilities in the cooperation level. These forces shall also be part of the national nuclear emergency response management. Emergency resources and capabilities shall be shared over the region or throughout the country by effective coordination and organization.
 Recommended modification action No. 9: Information release procedures shall be refined according to the characteristics of nuclear accident. Nuclear facility information transparency shall be enhanced to increase the public acceptance.
 Recommended modification action No. 10: Recent development and trend of international nuclear safety regulations and standards shall be studied and traced, so that we can keep up with the advanced level in the world and promote the continuous safety improvement of civil nuclear facilities.
 Recommended modification action No. 11: Management to the restricted planning zones around the nuclear power plants shall be enhanced to control the population increase in the zones strictly. It is forbidden to set up and expand the big enterprises and resident living areas until the proposal would be approved by national development and evolution agency, national energy administration and NNSA.
3.2 Nuclear safety plan
Another important action after Fukushima is the formulation of nuclear safety plan[5] in China, which has been just approved by the State Council together with the nuclear safety inspection report. The nuclear safety plan sets up the overall working goals for nuclear and radiation safety by 2020, and these working goals are specified into detailed objectives, and corresponding support projects and programs are also planned for each of them.

Objective in the field of nuclear facility safety improvement
Operating units shall maintain the excellent operation performance. INES level 2 events shall be avoided; events and accidents beyond INES level 3 and more shall be prohibited definitely. New nuclear units shall have sufficient measures for severe accident prevention and mitigation. Severe core damage frequency per reactor year shall be lower than 10-5, frequency of large release of radioactive material per reactor year shall be lower than 10-6.
 Objective in the field of nuclear accident defense
Safety modification actions shall be taken to increase the capabilities against external events and severe accident prevention and mitigation.
 Objective in the field of emergency response
The capability construction of emergency control, emergency response, emergency monitoring and emergency technical support at different levels of government and organizations shall be enhanced accordingly. Engineering contingency capabilities in case of nuclear accident shall be established in a consistent and coordinative manner. Emergency resources and equipments shall be increased.
 Objective in the field of nuclear safety regulation
The national R&D base for nuclear and radiation safety regulatory techniques shall be completed primarily, as well as the technical support platform, to own the relatively independent and complete capabilities of safety analysis and assessment, calculation verification and experimental verification. National network of radiation environment monitoring shall be completed, reaching the capability construction criteria by 100% in the province level and national level.
The new nuclear safety plan foresees that in 2020, safety of the nuclear facilities under operation and construction will be enhanced continuously. All the new units after 13th five year plan shall strive from the design for the practical elimination of the possibility of large release of radioactive materials.
Nuclear safety plan is actually in cooperation with the nuclear safety inspection report. It defines phased arrangements (immediate, by 2013 and by 2015) of the modification action recommendations proposed by the inspection report for the operating units, as follows. There are similar arrangements requirements also for the units under construction.
 Immediate modification actions
(1) Implementation of anti-flooding measures of doors, windows, ventilations, penetrations based on the careful re-examination one by one.
(2) Installation of portable power supply, portable pumps and new adequate interfaces, taking into account the balanced requirements of reactor core cooling, spent fuel pool cooling, prevention of seal LOCA and necessary post-accident monitoring.
 Effectiveness assurance measures to the seismic monitoring and recording system, and the improvement of the seismic response capabilities in the nuclear power plants,

 By the end of 2013
(1) Put into effect the flooding prevention measures of each nuclear power plant based on the possible scenario evaluations; Qinshan Nuclear power plant shall finish its specific modification project against flooding.
(2) Complete the re-evaluation to the seismic and tsunami effect on the coastal nuclear power plants, as well as the necessary modification.
(3) Develop severe accident management guidelines for each nuclear power plant and put it into effect.
(4) Evaluate the availabilities of systems and equipments used for severe accident and the possibility of hydrogen explosion, and take modification actions accordingly.
(5) Carry out safety margin analysis and evaluations under external events
(6) Carry out the research about the response solution in case of multiple units entering emergency states simultaneously.
 By the end of 2015
(1) Carry out the external event PSA of the nuclear power plants.
In order to assure the implementation of the plan, the plan also sets up a set of management assurance measures in the following areas.
(1) Accelerate the development process of the law of atomic and the law of nuclear safety, as well as the standards and guidelines, to refine the regulation foundations
(2) Optimize the management and regulatory structure and enhance the regulatory efficiency.
(3) Improve policies and institutions, especially for licensing permit and nuclear safety responsibility clarification among the nuclear cooperation company, the licensee company and the professional service company.
(4) Promote the nuclear safety culture framework to assure the effective quality assurance implementation with all the parties involved in nuclear matters.
(5) Enhance the human resource training and education，including establishing the shared network by government, universities, commercial training agencies and utilities.
(6) Enhance the international collaboration activities in the fields of cooperation research, information exchange, experience feedback, peer review, emergency response and assist and so on.
Expand the pubic involvement to increase the public confidence, e.g. building the information communication platforms in a open and transparent manner, increasing the nuclear knowledge spreading in basic educational level, and the public relationship maintain solutions in case of nuclear crisis
(7) Ensure the financial support and investigation based on the sufficient utilization of the government leading roles and multiple investigation mechanisms.

There are still other work items underway. Obviously, a new round of discussions of safety enhancement and debates on development pace and scale of nuclear power is taking place, which is actually very much beneficial for the healthy and sustainable development of nuclear power in the future. The latest nuclear development plan has not been approved and released by the government. It seems that nuclear electricity generation capability of 60~70GW by 2020 is likely. It is generally believed that China will continue its policy of intensive utilization of nuclear energy, and nuclear power will become one of the main contributors in the Chinese energy economy, in particular in the power generation sector.
4. Summary
China’s fast economic growth in the past decades triggered correspondingly fast growth in both primary energy supply and power generation. Various studies on the mid-term and long-term economic development in China have all predicted the continued economic and energy demand growth in the coming decades. Energy supply assurance to support the economic growth has already become a tremendous challenge.
Although China is very actively implementing renewable energy programs, their contributions seem to be limited in the overall energy supply picture. Environment protection and the reduction of green-house gas emission present increasingly more rigid boundary conditions on the energy supply economy. Nuclear energy is a practical energy source which can help to greatly ease the challenge, and will be expectedly an important part in the energy economy of China.
Nuclear safety has always been the highest priority in the development of nuclear power. Nuclear safety performance in China has been very good. The excellent operational records which Chinese nuclear power plants have got during the past decades constitute a strong basis for the continuous nuclear power development. After Fukushima, a series of actions aiming at enhancing nuclear safety are being taken to draw lessons from Fukushima. A relatively large number of nuclear power plants are being operated, constructed or under planning. It is believed that nuclear power will play increasingly important roles in the Chinese energy economy.

Reference
[1] BP Statistical Review of World Energy, June 2012.
[2] http://tj.cec.org.cn/tongji/
[3] http://news.xinhuanet.com/newscenter/2007-10/24/content_6938568_3.htm
[4] Integrated safety inspection and examination report for the civil nuclear facilities in China, June 2012
[5] The 12th five year plan and the 2020’s perspectives on the field of nuclear safety and radioactive pollution prevention and rescue, June 2012

SUN YULIANG