The Rooppur Nuclear Power Plant (RNPP) is the largest energy project in Bangladesh. It comprises of two units – each having power generation capacity of 1,200 MW. Prime Minister Sheikh Hasina inaugurated the pouring of the first nuclear safety-related concrete at unit-1 and unit-2 respectively on 30 November 2017 and 14 July 2018. Bangladesh Atomic Energy Commission (BAEC) prepared the safety report of the plant at international standard and the Bangladesh Atomic Energy Regulatory Authority (BAERA) issued the concrete pouring license on the foundation of reactor plate, unit-1 on 18 February 2018, and unit-2 on 08 July 2018 after examining the safety report. The RNPP unit 1 and unit 2 will be producing electricity on experimental basis at the beginning of 2023, and finally in 2023 and 2024 respectively. Presently, the construction works of RNPP for the development of containment walls, outer walls, inner walls, reactor pit walls, core catcher placement foundation and core catcher walls are in progress with due compliances of the design and other regulatory requirements of BAERA.
Over the last several years, Bangladesh has made a significant progress in power sector. The government has undertaken various projects to increase the generation of electricity to support the economic development. Bangladesh has fixed generation targets of 24,000 MW, 40,000 MW and 60,000 MW in the year 2022, 2030 and 2041 respectively. The Power System Master Plan (PSMP) aims to ensure supply of electricity for all citizens and economic sector at affordable costs through a well-balanced generation environment. About 70% of the power generation will be covered by coal and gas and the remaining 30% by nuclear, hydropower, renewable and imports from neighboring countries. The RNPP has taken all necessary safety measures with latest technologies that are expected to cover all possible disasters. The generation of electricity by using nuclear power will make a revolutionary change in the economic sector and improve the people’s living standard.
Development of RNPP
The importance of nuclear power plant in Bangladesh is now well recognized. Nuclear power is environmentally friendly and cost effective option. In this process, there is no emission of carbon-di-oxide, a major factor for global warming and climate change, nor produces any harmful chemical that causes disasters like acid rain, or depletion of ozone layer. That is why this plant is safe.
Nuclear power plants involve very low fuel cost compared to fossil fuel plants. The new generation nuclear reactors are more reliable and efficient than the earlier ones. Bangladesh is introducing the new technology in RNPP for ensuring more safety. Generation of electricity from nuclear power is a dependable option. In this process, a stable and easily changeable fuel Uranium (135U) is used. The amount of free energy contained in nuclear fuel is million times higher than that of the chemical fuel like gasoline. With nuclear power plant, it is possible to generate more than 2000 kWh electricity by using only one gram of Uranium. Whereas, several tonnes of coal is required for the same. Moreover, the cost of electricity generation in this process is much lower than other conventional options.
Bangladesh has created the legislative framework through a comprehensive nuclear law “Bangladesh Atomic Energy Regulatory Authority Act 2015” that empowers the authority with the power, independence and resources it needs to carry out its function and responsibilities. The authority, BAERA, is developing the licensing process, performing regulatory supervision of project activities at different phases, and ensuring the highest standards of safety and security measures. The RNPP has started developing for its necessary manpower through the cooperation of international partners and contract signing country by education and training programs abroad to make available trained manpower during the commissioning and operation phases.
Bangladesh signed an intergovernmental agreement (IGA) with the Russian Federation for cooperation concerning the construction of two VVER-type reactor power units at Rooppur on November 02, 2011. The scope of the IGA included design, construction, installation, start up, commissioning and warranty operation, and also financing, fuel supply during the entire operational period, take-back of spent fuel to Russian, education and training of RNPP personnel, cooperation for operation and maintenance of the plant, management of radioactive waste and decommissioning of the plant and other services as required. Under the provision of the IGA, the governments of Bangladesh and Russian Federation signed an intergovernmental credit agreement (IGCA) of US$ 500 million state export credit on 15 January, 2013 for financing the preparatory stage construction activities. Bangladesh also signed another IGCA amounting $11.385 billion on 26 July 2016 for financing the construction of the plant.
Safety Features
The RNPP is one of the latest addition to the Russian VVER (Water-cooled Water-moderated Power Reactor) reactor plant of AES-2006 (VVER-1200, V-392M) technology by adopting the site specific safety features. The design of unit 1 and unit 2 reactor is developed based on VVER-1200 reactor plant with elaboration of designing, equipment manufacturing, construction and commissioning experience of Novo Voronezh NPP-II and experiences in operation of the most recent VVER reactors in Russia and abroad. The high quality of engineering solution and design documentation has been developed based on application of modern Russian rules, regulations and standards, recommendations of international agencies, domestic regulatory requirements, and site-specific seismic and climatic conditions.
Safety Layer
The design of RNPP meets the high level of safety standard. The lessons learnt from the major nuclear accidents of Chernobyl, and Fukushima were incorporated in the design by defense in-depth principle. Reliable five layers of barriers prevent the radiation exposure to people and environment even in the worst-case scenario, as shown in Figure.1.
Fig. 1: Five layers of barriers against the radiation exposure to people and environment:
Source: Ministry of Science and Technology, July 2018
The safety system of RNPP is based on active safety systems with both normal and emergency power supply. To prevent severe accidents, or to mitigate their consequences, passive safety systems are foreseen which function without the involvement of NPP personnel, and do not require any power supply. In case of a severe accident with extreme power loss due to grid failure (like Fukushima NPP accident), the RNPP will remain safely automated shut-down for 72 hours without the involvement of external assistance and off-site power supply. The active and passive safety systems with 2-4 times effectiveness and diversity will make this plant a really safe one. The active safety systems includes emergency and planned cool down protection, high pressure emergency injection, emergency boron injection, emergency feed water system, emergency gas removal, primary and secondary circuit overpressure protection, spray system, containment isolation, intermediate circuit and service water supply, ventilation and essential power supply system. The passive safety system includes quick boron injection, emergency core cooling, hydro-accumulators, passive containment heat removal, passive steam generator heat removal, hydrogen concentration monitoring and hydrogen passive recombination, inside containment, molten corium trap and cool down system. There will also be emergency power supply and standby diesel power system.
Safety Systems from Natural and Manmade Disasters
The RNPP has specific safety features with detailed design that are safe from natural and manmade disasters, and any other disastrous situation. A systematic safety measures have been taken in RNPP according to the plant site safety design, i.e. seismic design parameters, and other parameters relating to natural disasters: cyclone, tornado, floods, temperatures, winds, any meteorological constraints and manmade hazards.
A systematic engineering-geological study completed at the project site. Necessary equipment are installed and the aero-meteorological model, the engineering-hydro-meteorological model, and the seismic-geotectonic models have been developed. The design of seismic hazard measures provided the seismic design parameters: average safe shutdown earthquake intensity 8 points on MSK-64 scale (peak acceleration 0,33g) and average design basis earthquake intensity 7 points on MSK-64 scale (peak acceleration 0.17g).
Based on comprehensive hydrological, hydraulic and morphological studies of the site, the scenario of the maximum probable flood formation has been determined. In prediction of the MPF scenario, the combination of all possible hydrological events were taken into consideration with probability of 0.01% (with frequency once per 10,000 years): (1) simultaneous flood peak occurrence including precipitation on all major river basins, (2) Bay of Bengal water fluctuation impact, (3) additional precipitation and sea level rises due to global climate change impacts, and (4) a failure of the Farakka dam located higher up the river Ganges (Padma).
The engineering protection against all possible flooding is provided by the design. In addition, the catch drains are designed for removal of surface and overflow waters from the lower relief areas to ensure normal operation of the plant related to I-III safety categories. The RNPP site protection design is also developed from the possible river erosion of Padma.
The project site is located in tropical climate zone. The detailed engineering and climatic survey on extreme winds including a tornado and extreme temperatures were performed. The observed air temperature: max: +44°С and min: +3.5°С. Based on the study of the climatic conditions, the design parameters of the ventilation systems, plant cooling capacity, fluid coolant consumption parameter, supply pipelines diameters, air conditioning systems, architectural and planning concepts of the rooms have been designed. With due consideration of the quality and physio-chemical properties of the water of the Padma River with water level, the chemically demineralized water preparation system, structure of the cooling system (two cooling towers per unit), and auxiliary power supply system have been designed.
The feasibility evaluation, site engineering survey and environmental impact assessment have justified the techno-economic feasibility of the project and corroborate the site for nuclear power plant construction. The outcomes of these studies also refer for the site location, safety infrastructures, and its protection from any adverse natural or manmade effects.
Conclusions
The construction of this power plant is going to enhance the development of social, economic, scientific and technological potential of the country and promoting Bangladesh to become a member of the nuclear power producing countries. The plant is using similar technology to Kudankulam NPP in India. The RNPP is expected to provide not only low cost electricity but also provide clean, reliable electricity 24X7 basis so that people can meet their daily basic needs.
The plant will play an important role in providing a stable baseload and ensure energy security in Bangladesh. The Rooppur Nuclear Power Plant is a milestone in the national development program.
AKM Monowar Hossain Akhand, Former Additional Secretary, Ministry of Science and Technology, Email: makhand14@yahoo.com
