[en] Consideration is being given to the main factors (safety, sphere of application and fuel supply), dictating competitiveness of nuclear power at the world power market. Requirements of reactor safety are formulated on the basis of risk assessment including analysis of the maximum credible design basis reactor accidents. The social estimation is based on the condition of providing the minimal probability of occurrence of even one accident with dangerous radioactive effluents. The economical estimation derived from the condition that the damage from serious accident doesn't exceed several percent of the reduced power generation cost. It is shown that when determining possible scales of nuclear power development and requirements for reactors of a new generation allowance must be made for the structure of heat production both with respect to the type of energy-transfer medium (steam, hot water, high-temperature coolant) and to its temperature potential, as well as for the factor of registered capacity