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The variety of possible solutions for the integration of heat pumps (HP) into the circuits of generation facilities dictates the need for preliminary selection of the most promising options. Determining the maximally economically efficient HP capacity may be the key limiting factor for the potential range of solutions. The purpose of the study is to analyze the influence of the type of power equipment of a thermal power plant (TPP) on the choice of HP capacity. In the course of the study, we identified factors that can influence the choice of HP capacity. The correlation between the limitation of the maximum capacity of HP (from the point of view of break-even operation in the electricity market) from the electric capacity and the efficiency of the TPP equipment was established. The ranges of HP capacity for the most common types of TPP power equipment in the Russian Federation were determined. The maximum HP capacity for TPPs based on a steam turbine unit (STU) of type K-300-170- 1P was determined. The method proposed in the paper allows limiting the number of circuits options, as well as TPPs and external conditions suitable for the use of HP. Firstly, under the conditions of a given power system and fuel prices, it is possible to determine the type of power equipment of a TPP in combination with which HP can be used. Secondly, under the conditions of a given power system and type of equipment, the maximum fuel price at which HP can be used at thermal power plants can be determined. Thirdly, under the conditions of a given type of equipment and fuel price, it is possible to select an energy system (region) in which it is possible to build a TPP with HP. It was found that increasing the efficiency of thermal power plant equipment contributes to increasing the HP power capacity and expanding the range of external conditions under which the use of HP becomes rational. It was verified that for TPP equipment of a given type, the use of HP is more rational when operating in cogeneration mode. It was found that, all other conditions being equal, an essential factor determining the range of HP capacity is the electric capacity of TPPs. [ABSTRACT FROM AUTHOR]

• Foundations of experimental geothermic studies were significantly improved. • Advanced technique was applied to study the Volga-Ural oil and gas basin. • Field experiment included 7 cycles of temperature logging during 186 days of well shut-in. • Unique data on temperature and its gradient behavior after drilling were obtained. • A significant increase in heat flow with depth was established. • The necessity for new, special experimental estimations of heat flow is demonstrated. • Thermal core profiling is needed for estimation the detailed variations of heat flow. • One more prove that heat flow data obtained with common technique are unreliable. The paper describes the results of experimental geothermal studies of the formation surrounding Savitskaya-300 well (depth 3555 m) drilled in the Volga-Ural oil and gas basin (Orenburg region, Russia). The work was aimed, firstly, at obtaining geothermal data for basin modeling and, secondly, at improving the instrumental and methodological foundations of experimental studies. Continuous core profiling of the rock thermal conductivity, volumetric heat capacity, and thermal anisotropy was performed on all 2886 recovered core samples with the total length of 329.1 m. Additional measurements were conducted at fluid saturation and elevated temperatures. For non-cored intervals, the rock thermal properties were determined from well-logging data and via measurements on rock cuttings. The studied formation is characterized by high thermal heterogeneity at both the level of strata (horizons) and individual samples. Significant thermal anisotropy up to 1.50–1.66 in the lower part of the well has been observed. To obtain data on vertical variations of equilibrium temperature and its gradient, temperature logging was performed 7 times within the 2 to 186 days of well shut-in. New data on the recovery of temperature and its gradient after drilling are important for the practice of applied and fundamental geothermal surveys. A significant increase in heat flow with depth was established based on the results of temperature gradient and rock thermal conductivity determination for 34 depth intervals. The observed general vertical variation in the whole depth range of the well up to ∼3.3 km depth can be attributed to paleoclimatic effect in the Late Pleistocene-Holocene, while the sharp increase in heat flow at ∼3.3 km within Fransian sediments is possibly due to advective heat transfer by fluid filtration. The apparent heat flow was established to be 84.3 mW⋅m−2 in the lower section of the well, below 3.3 km. The value may be close to the steady-state heat flow value, which is 84% higher than the previous published average data for the studied area. [ABSTRACT FROM AUTHOR]

In Russia, the legislative support for the construction and operation of heating systems is permanently developing and improving. The Federal law "On heat supply" adopted in 2010 is the basic and most important document that regulates the work of heating systems. Moreover, the country has more than 10 additional documents that regulate this industry, and a great number of documents that establish rules for building and operating energy systems. The paper presents the main documents that regulate the heat supply industry in the Russian Federation, and a brief description of the main stages of heating system life cycle and problems solved in each of them. Despite the national policy of energy conservation and energy efficiency enhancement, there are still problems related to heat supply management due to large extension, complexity and a variety of types and structures of the systems. The main cause of the poor heat supply efficiency in Russia is explained by a considerable change in the structure of heat loads that has occurred of late years, a decrease in the loading of the main generating equipment and heat networks, which amid other things is fostered by an increasing wear of the systems. Upgrading of generating capacities and heat networks is considered in the framework of long-term investment projects for their modernization and expansion. The obtained solutions are reflected in the Schemes of urban heat supply. This paper proposes solutions aimed at enhancing the effectiveness of decisions made in the field of heat supply. It formulates the proposals on organization and regulation of the activities of all the participants in heat supply in the stage of long-term planning of heating system expansion, because well-founded and rational planning of construction and expansion of the systems is a basis for their efficient operation. [ABSTRACT FROM AUTHOR]

Experiments on determination of main thermophysical parameters (heat conductivity, heat capacity, thermal diffusivity) and thermokinetic characteristics (activation energy of pyrolysis and flaming) of typical forest combustible materials and their mixtures, taken from the Siberian, Central, Southern, and Far Eastern Federal Districts of Russia, have been performed in the wide temperature range 298–423 K corresponding to the initiation of thermal decomposition and subsequent flaming of forest combustible materials. Results of these experiments were compared with experimental data obtained by other researchers. A database, which can be used in the mathematical simulation of the thermal decomposition and flaming of forest combustible materials as well as in the determination of conditions necessary for the localization and suppression of a forest fi re, has been developed. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of recent eastern Siberian land surface changes, such as water surface expansion, on water-energy fluxes and precipitation and focused on land surface parameters using a three-dimensional atmospheric model [the Japan Meteorological Agency Nonhydrostatic model (JMA-NHM)]. Five parameters were set (viz., surface albedo, evaporative efficiency, roughness length, heat capacity, and thermal conductivity), and a response of evaporation and precipitation was evaluated. Increased precipitation corresponded to 75% of the increased evaporation on interparameter average, indicating strong land-atmosphere coupling. Water-energy flux and precipitation responses to water surface expansion were evaluated by two methods: JMA-NHM and the parameter sensitivity method. The latter method used a linear combination of parameter sensitivity on the fluxes and precipitation and parameter changes with land surface change. JMA-NHM demonstrated an increase in evaporation and precipitation and a decrease in downward shortwave radiation with low-level cloud increases. The parameter sensitivity method gave the same order as JMA-NHM in the estimation. This method has minimal calculation cost; thus, water-energy flux and precipitation response with further water surface expansion and decreases in forest area were simulated, producing various land surface data. The enhancement of the precipitation response to evaporation was weak for further water surface expansion in the largely expanded water surface area; however, the ratio increased dramatically for the small water surface expanding area, indicating intense water cycle enhancement at the beginning of water surface expansion. Although grassland formation from forest has minimal impact, if incoming downward shortwave radiation were to increase because of the disappearance of the forest shading effect and the water surface formed by permafrost melting, the water cycle would be enhanced intensely. [ABSTRACT FROM AUTHOR]