The access to reliable sources of energy is the key to sustainable development of mankind. The major part of the energy consumed by people is generated with a chemical reaction of fossil fuel burning. This leads to quick depletion of natural resources and progressing environmental pollution. The contribution of the renewable energy sources to the general energy production remains insignificant.
A modern 1,000 MW coal-fired thermal power plant (TPP) burns 2.5 million tons of coal per year and produces significant amount of solid and gaseous waste. TPPs are the largest consumers of atmospheric oxygen and sources of carbon dioxide. A nuclear power plant (NPP) of the same power consumes less than 50 tons of fuel per year. Environmentally significant NPP’s waste (liquid, solid and gaseous) is carefully collected, reduced in volume (evaporation, filtering, compaction, incineration, etc.) and securely isolated from the environment at the plant. The annual volume of waste for storage is less than 100 m3. The waste is under the control of a special NPP’s service and regulatory authorities.
The energy of fission reaction millions of times exceeding the energy of burning has an enormous potential that mankind can receive.
Four hundred and thirty-three nuclear power units with a total capacity of about 400 GW exist in the world. The accident at the Fukushima Daiichi NPP in Japan in March 2011 caused anxiety about nuclear safety throughout the world and raised questions about the future of nuclear power. Now, it is clear that the use of nuclear power will continue to grow in the coming decades, although the growth will be slower than was anticipated before the accident. Many countries with existing nuclear power programmes plan to expand them. Many new countries, both developed and developing, plan to introduce nuclear power. Some countries, such as Germany, plan to abandon nuclear energy. The IAEA’s latest projections show a steady rise in the number of NPPs in the world in the next 20 years. They project a growth in nuclear power capacity by 23% by 2030 in the low projection and by 100% in the high projection [1,2].
The basis of modern nuclear power comprises water-cooled nuclear reactors which use the energy potential of natural uranium inefficiently (thermal reactors). The thermal reactors use isotope U-235 in which the content of natural uranium is <1%. Breeder reactors are capable of using the significant part of energy potential, which is unavailable to thermal light water reactors. As a result, the same starting quantity of uranium can produce 50 times more energy. These reactors can transform U-238 into fissile Pu-239 in larger amounts than they consume fissile material. This feature is called ‘breeding’ .
The key problem of using the basic benefits of nuclear power is to ensure the safety of its use, as well as decommissioning and reliable isolation of process waste from the biosphere. The long-term large-scale nuclear power should possess guaranteed safety, economic stability and competitiveness, absence of the raw material base restrictions for a long period of time and environmental sustainability (low waste). The nuclear power systems with fast neutron reactors and liquid metal coolant can satisfy these conditions.
More than 40 years of Russian experience in the field of construction and operation of sodium fast reactors makes it possible to summarize and analyze the ecological features of reactors of this type, the possibility of their use for sustainable energy supply of mankind and solving environmental problems.
closed nuclear fuel cycle, collective dose, fast breeder reactor, nuclear energy systems, nuclear power plant, safety
 Amano, Y., Nuclear power in the 21st century, https://www.iaea.org/sites/default/files/ publications/magazines/bulletin/bull54-1/54104710202.pdf
 Bychkov, A., Nuclear power today and tomorrow, https://www.iaea.org/sites/default/ files/publications/magazines/bulletin/bull54-1/54104710707.pdf
 Ponomarev-Stepnoy, N.N., Zrodnikov, A.V. & Koltun, O.V., Perspectives of development and implementation of closed fuel cycle. Proc. of the 9th International Scientific Technical Conference ‘Safety, Efficiency and Economics of Nuclear Power Engineering’, Rosenergoatom: Moscow, pp. 19–22, 2014.
 Tashlykov, O., Shcheklein, S., Sesekin, A., Chentsov, A., Nosov, Y. & Smyshlaeva, O., Ecological features of fast reactor nuclear power plants (NPPs) at all stages of their life cycle. 1st International Conference on Energy Production and Management in the 21st Century: The Quest for Sustainable Energy; Russian Federation: Ekateringburg; 23–25 April 2014 . WIT Transactions on Ecology and the Environment, 190, pp. 907–918, 2014.
 Nosov, Y.V., Smyshlaeva, O.Y., Tashlykov, O.L. & Shcheklein, S.Y., Ensuring of ecological safety over a long period of exploitation of the fast breeder reactor on the example of Beloyarskaya NPP. Alternative Energy and Ecology, 4(108), pp. 64–68, 2012.
 Tashlykov, O.L., Shcheklein, S.E., Bulatov, V.I. & Shastin, A.G., Problem of the lowering of the nuclear power plant personnel exposure. Communications of Higher Schools, Nuclear Power Engineering, 1, pp. 55–60, 2011.