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Knowledge of the nature of the energy load alterations not only in time, but also in space will allow achieving the optimal structure of energy sources in the city and thereby reducing unproductive energy costs of energy resources and increasing energy efficiency. Changing the paradigm of power supply systems development towards the development of small distributed power production, intellectualization and demand management requires a more accurate understanding of the planned local loads in the city. At present it is still difficult to obtain such data; it requires analysis of many sources and, consequently, takes a lot of time. The article presents a possible algorithm of formation of the space-time profile of energy resources consumption. At the heart of the load disaggregation there is a spatial distribution of consumers in the city, estimated by the density of the distribution area of buildings of energy consumer groups. The dimension of the model is not limited in both temporal and spatial resolution: the model is flexible and can be adapted to different cases and local conditions. The proposed algorithm has been applied to the modeling of the profile of electricity consumption in St. Petersburg. The profile is based on an annual graph of electricity consumption by hour (8760 values). The spatial resolution of the model ranges from hundreds of meters to several kilometers and depends only on the availability of initial data. In the example, the division of the city territory into administrative districts (18 districts of St. Petersburg) is used as a spatial unit. The obtained results showed their logicality and compliance with empirical observations.

The goal of the study is to propose the basis for the concept of expanding the fuel balance in Russia through the development of a closed-loop resource cycle. We propose to use the criterion of energy potential of waste to generate new data on the resource base of the fuel and energy complex at the regional level. In order to form a reliable source for replenishment of the resource potential of the fuel and energy complex through waste recovery, the basic principles of data collection are proposed and the methodology for determining the energy potential at the city level is demonstrated using municipal solid waste (MSW) in 11 Russian cities as an example. The results of the evaluation have shown that due to energy recycling, MSW can cover from 2.11% to 6.01% of the heat demand of the territory under consideration. In the study, we propose to supplement the maximum involvement of waste in the fuel and energy balance (FEB) in Russia with the criterion of optimization of the energy balance at all levels and to distinguish a separate column “energy potential of waste” in the balance structure. This approach fundamentally changes the structure of the balance and gives the grounds for revision of plans for production and transportation of traditional energy resources.

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The problem of the emergence of turbulence is one of the unsolved problems of physics and technology of the 20th century. It is noted that in order to understand the emergence of turbulence in a viscous heat-conducting gas, it is necessary to take into account the compressibility of the medium. A definition of turbulence in a viscous heat-conducting gas is given, which is a cyclically repeating process of the emergence and decay of coherent vortex structures described by a vector wave equation. The decay of vortex structures is accompanied by an explosive, asymptotic increase in pressure pulsations, which triggers a new cycle of turbulence generation. The emergence and decay of coherent vortex structures in the boundary layer on a plate and in a round jet is considered.