In article the theoretical explanation of business cycles offered by N. D. Kondratyev is compared with modern conditions of economic development. The need to consider how the relative scale of «creative destruction» vary from cycle to cycle and affect this development is proved. Economic advisability of use of technologies of the previous long waves after raising of the next long wave is discussed. Existing views on the interaction of technologies of different long waves are considered. The simple model of the accumulating (overlapping) generations of technologies when the new technological paradigm is formed, is offered. In contrast to the overlapping generations model of the population, where generations have a fixed term of life, here the duration of the existence of certain technologies is not an exogenous parameter. The attention is focused on infrastructural conditions for economic development. The model illustrates process of formation of long waves even at monotonous nature of development of technologies. The presented option of formation of these waves is beyond the scheme corresponding to «a technological determinism» in an explanation of business cycles. The part of parameters of model reflects institutional conditions of economic development, in particular, business lending conditions. It is shown that reduction in price of resources required for the new technology may be the cause of the observed shortening of the Kondratyev cycles.