*3.1. Nuclear Energy Sector*

Nuclear industry, accounting for 4.5% in the global energy balance, has already made a considerable contribution to energy sector development (Figure 3), due to the relatively low cost of electricity generation [55]. The development dynamics of the nuclear energy sector differ greatly in various countries, because of varying available resources and access to alternative sources of energy, as well as project experience.

Prospects for its further development are questionable. On the one hand, the low production cost of energy generation, as well as the higher efficiency of the plants (the majority having a capacity use rate of more than 80%) [56], could mitigate the technological transformation of the energy sector. On the other hand, the diagram shows that sharp declines in nuclear energy generation are caused by accidents at plants that directly influence not only the energy generation process, but also produce fears on the expediency of the further use of nuclear energy. Here, for example, a final decision about the immediate decrease in the share of the nuclear energy in the country balance was taken by Germany in 2011 after the accident at Fukushima and the first-step measures included the shutdown of power units commissioned before the 1980s.

**Figure 3.** Dynamics of nuclear energy generation volumes. Based on BP Energy Overviews.

The problem of existing physical depreciation of energy generating facilities is topical for the nuclear energy sector even today. As of the end of 2018, the number of nuclear reactors in the world amounted to 450 [57], 281 of which (62.4%) were more than 30 years old, 26% were aged 10 to 30 years, and only 11.6% were younger than 10 years old. In accordance with IEA data [58], the highest average ages of nuclear plants are seen in the USA (39 years old), Europe (35 years old), Russia (31 years old) and Japan (29 years old). The highest shares of nuclear plants under 10 years old are observed in China (80%), India (40%), Russia (25%) and Korea (24%).

Strengthening security measures taken during the construction of the third-generation reactors enables the mitigation of risk of accidents, but increases the unitary cost of the generated energy (more than doubling the cost, compared to fully depreciated facilities) [59]. In general, with the increasing wear and tear of the reactor, the risk of unforeseen incidents increases, and therefore, activities in the field of nuclear energy should be accompanied by the availability of an appropriate license confirming the safety of power generating facilities.

It can be said that nuclear energy has some advantages compared to other energy technologies. First of all, a comparatively low energy generation cost with a minimal carbon footprint. Secondly, technology readiness with high technical efficiency. Thirdly, the technological scalability of both smalland large-scale capacities, which may ensure stable and uninterrupted energy generation.

Despite this, there are three key barriers that do not allow a significant expansion of nuclear plant usage. Firstly, the development of nuclear energy generation is associated with the development of nuclear weapons, which is a very negative and destabilizing factor [60].

Secondly, notwithstanding their higher reliability, global history knows examples of man-made catastrophes, which has produced a very adverse effect upon acceptance of the technology. To restore its image, grea<sup>t</sup> pains must be taken in terms of marketing and notifying society about the safety measures taken at modern energy generating facilities [61].

Thirdly, one of the most complicated problems is the handling of nuclear waste [62], requiring significant financial costs on the one hand and availability of hi-tech facilities preventing radioactive contamination of the environment on the other.
