Reduction In Natural Gas Consumption Research Articles

Advancing sustainable laundry practices utilizing waste heat from commercial laundry facilities

To enhance efficiency and reduce operational costs in mechanical drying for energy equipment, this study introduces a novel sustainable laundering approach using an innovative waste heat recovery (WHR) method in commercial laundry facilities utilizing gas dryers and boilers as waste heat sources. The proposed WHR system serves as a pre-dehumidification stage, where laundry undergoes centrifugation, initial drying in the WHR chamber, and final drying with a gas dryer. Building on established foundational data and models for heat and moisture transfer from previous research, this study rigorously evaluates the performance of the proposed system. The evaluation integrates three mathematical models to simulate the WHR laundry drying system: heat exchange, laundry drying, and mass movement. The laundry drying model utilizes the thermodynamic energy of moisture for water transfer. Various simulations are conducted, adjusting the laundry's forward speed and interval. The effectiveness of the system is assessed using three indicators: quantity of laundry processed, latent heat load, and degree of laundry dryness. The simulations reveal that the system can handle an annual latent heat load between 970.1 and 1827.1 GJ, corresponding to a reduction in natural gas consumption of approximately 21,560–40,600 m3 and achieving laundry dryness levels of 40 %–68.2 %.

Data-driven optimal placement of minichannel-based solar water heater using satellite-derived and ground-telemetry weather information

The aluminum minichannel solar collector is a novel technology for solar water heating. Minichannel-based solar collectors have higher thermal efficiency than conventional flat plate collectors and do not suffer from potential loss of vacuum as evacuated-tube collectors. This technology can play a significant role in reducing natural gas consumption that translates into lower greenhouse gas emissions to the atmosphere. However, the performance of solar collectors depends on the geographical location of the installation due to solar resource availability and weather pattern. The potential reduction in natural gas consumption using aluminum minichannel solar collectors is assessed using solar irradiance, ambient temperature, and wind data obtained from ground weather station and satellite-derived data. A data-driven numerical analysis is performed using a validated solar water heater (SWH) model, population, and natural gas consumption data for the entire state of California to assess the best locations to install these systems. The SWH model is validated based on data collected from an actual SWH system installed at a single-family house in Northridge, California. A K-means clustering method is then applied to select the best regions for installation of this technology. Based on performance, population density, and natural gas consumption, the regions of Southern California and the Central Valley are chosen as having the highest potential for reduction of natural gas consumption. The analysis was performed from weather data obtained based on two full years (2020 and 2022), where the effect of COVID-19 (year 2020) is observed as having higher water tank temperatures and higher solar fractions, which could be associated with lower hot water consumption.

Impact of steam flow into a combustion chamber of a contact gas-steam installation on its energy characteristics

Relevance. Reduction of natural gas consumption and emissions of harmful substances into the environment based on introduction of water vapor into a combustion chamber of a contact gas-steam installation. Aim. To carry out numerical studies on the influence of relative steam flow into the combustion chamber of the contact gas-steam installation on its energy characteristics. Objects. Contact gas-steam installations based on gas turbines with steam injection into the combustion chamber. Methods. Numerical methods based on material and energy balances of systems and elements of gas-steam installations. Results. Based on the calculation of the thermal circuit of the contact gas-steam installation, the authors have studied the influence of the relative steam flow into the combustion chamber on its energy characteristics. It was determined that the absolute electrical efficiency of the contact gas-steam installation increases linearly with growth of relative steam flow into the combustion chamber. The range of changes in the relative steam flow into the combustion chamber strongly depends on the temperature of the gases behind the combustion chamber and the compression ratio in the air compressor; the smaller these parameters are, the greater the range of changes. The maximum efficiency of 56% for all options is achieved at the maximum relative steam flow into the combustion chamber. It was established that the excess air coefficient, depending on the relative steam flow rate, decreases linearly, and the higher the temperature of the gases behind the combustion chamber and the compression ratio in the air compressor, the greater the rate of decline and the smaller the range of changes in the relative steam flow rate. It was revealed that the efficiency coefficient strongly depends on the relative steam flow into the combustion chamber, the temperature of the gases behind it and the degree of compression in the air compressor; with increasing these parameters, it increases linearly. It was determined that the temperature of the gases at the outlet of the gas turbine also strongly depends on the relative flow of steam into the combustion chamber, the temperature of the gases at its outlet and the compression ratio in the compressor. With an increase in the relative flow of steam into the combustion chamber, this temperature increases linearly from 600 to 700°C, while the higher the temperature of the gases at the outlet of the combustion chamber and the compression ratio in the compressor, the higher the temperature of the gases at the outlet of the gas turbine. The authors revealed the dependence of useful work on a gas turbine shaft on the relative steam flow into the combustion chamber. With an increase in the relative steam flow, the useful work on the gas turbine shaft increases along the branch of the parabola. The higher the temperature of the gases behind the combustion chamber and the compression ratio in the compressor, the steeper the branch of the parabola, but the smaller the range of changes in the relative steam flow. It was established that with an increase in the relative steam flow, the gas flow to the gas turbine decreases according to a hyperbola. Moreover, the lower the temperature of the gases behind the combustion chamber and the compression ratio in the compressor, the more the gas flow to the gas turbine drops.

A novel temporal mixed-integer market penetration model for cost-effective uptake of electric boilers in the UK chemical industry

The UK chemical industry is the largest consumer of natural gas for process heating and power generation, with an annual consumption of 26.3 TWh. Reduction in natural gas consumption and associated carbon emissions can be achieved through electrification of heat. However, the adoption of electric boilers is lethargic due to economic barriers. Hence, market-based policy interventions are required. This study aims to accelerate the adoption of electric boilers in the UK's chemical industry, aligning with the UK's ambitious 2035 industrial decarbonisation goals while considering economic impacts, by designing market-based policy interventions and comparing two adoption patterns. A novel multi-period Mixed-Integer Market Penetration Optimisation Model is developed and applied to inform decisions about transitioning from natural gas to electric boilers. The model is applied to a case study of all the heating systems (490 boilers) in the UK chemical industry from 1 MW to 60 MW boilers. Results show that effectively implementing a gas tax, electricity subsidy, annual grant and carbon tax can generate sufficient demand-pull to reduce the cost of electric boilers from 30 to 85 % depending on the boiler size. A carbon tax starting at £280 per tCO2e and reducing to £170 per tCO2e coupled with electricity subsidies is essential for this transition. The policies are designed such that a win-win is achieved between government and industry; specifically, revenue from the carbon tax and gas tax is used to support the grant and electricity subsidy thereby achieving cost neutrality for government. At 100 % uptake of electric boilers in 2033, the total carbon emissions reduce by 89 %, which is above the 2035 UK industry goal of 60 % reduction. The research establishes a robust policy timeline that can drive industrial electrification in the UK's chemical sector. It highlights the need for a multi-faceted approach, incorporating various policy instruments to overcome the barriers of high initial capital costs.

Environmental and Economic Assessment of the Italian Energy Transition Scenarios

The aim of this work is to assess the environmental and economic impact of the Energy Transition of the Italian Electrical Sector, as planned by the PNIEC (Integrated National Energy and Climate Plan), published in December 2019, and by the scenarios, developed by Terna and Snam, updated to reach the Fit-for-55 objectives. The analysis of the historical trends related to RES (Renewable Energy Sources) capacity increase, allows comparing the historical effort with the one expected to reach the 2030 goals. In particular wind off-shore production is expected to have a larger impact than envisaged before. On the technical side, some scenarios assumptions are going to be revised to more realistic values. The technological and economic efforts, besides an estimation of the expected global environmental benefit, are assessed taking into account: i) the revised RES capacity increase, ii) the grid infrastructure enhancement, and iii) the envisaged installation of new storage and electrolyzer capacity. With flexibility items, ii) and iii), requiring a similar level of capital cost as the new RES capacity. The reduction in natural gas consumption in the different scenarios is expected to reduce both the Green House Gas emissions and the operating cost with a large impact on the average efficiency of the natural gas-fed power plants.

The Future of the Czech Gas Industry

In the Czech Republic, the gas industry is a key sector for ensuring the successful growth of industrial production and the growth of the standard of living. However, the set of Green Deal agreements recently adopted by the European Union envisages the gradual reduction of natural gas consumption and its replacement by ecologically produced (green) hydrogen. However, the production of green hydrogen in the Czech Republic is not yet industrially established, and its realisation will require considerable financial sums as investments in the relevant infrastructure. This will be reflected in a significant increase in the price of gas containing the prescribed proportion of green hydrogen. The planned addition of a certain proportion of hydrogen to natural gas will bring a number of complications to the gas industry. Production of a sufficient amount of green hydrogen, which should be added to natural gas, is not ensured in the Czech Republic or in the EU and will require considerable investment in the production infrastructure, which will in the final phase be transferred for the most part to the end consumer of the mixed gas. Total gas consumption will increase by 13%, as hydrogen has three times lower calorific value compared to methane, which is the majority component of natural gas. The reduction in greenhouse gas emissions will therefore be minimal or, taking into account the carbon footprint of the additional equipment needed for hydrogen production, even negative.

Standalone hybrid system energy management optimization for remote village considering methane production from livestock manure

Recently, many efforts have been done to overcome increasing fuel consumption. One of the vital solutions is utilization of standalone renewable energy resources hybrid systems. This paper attempts to develop a cost-effective methodology to ascertain optimal design and energy management for a remote village. Different energy resources such as wind and solar, fuel cell, and energy storage systems are employed to satisfy total demands including agriculture, residential, school, and health center. Different hydrogen production methods are proposed to verify the efficiency of the developed methodology. In the proposed village, different waste types such as rice husk, maize straw, livestock, and residential wastes are used to generate the required hydrogen for fuel cells to generate electricity. The main objective of the proposed methodology is minimizing the total cost of the village including total costs of each Distributed Generation (DG), cost of natural gas consumption, penalty for interruption the demands, and cost of CO2 emission. A Particle Swarm Optimization (PSO) algorithm is employed to solve the optimization problem by minimizing the total system costs while the customers required Loss of Power Supply Probability (LPSP) is satisfied. The suggested hybrid system not only increases the renewable energy penetration but also decreases the natural gas consumption. The results achieved in the course of the present study depict that utilization of energy produced from different types of wastes plays a significant role in conserving fossil fuels and overcoming the fossil fuels depletion. It is concluded from the results that there is about a 17.46% reduction in natural gas consumption when all available waste is utilized. In addition, considering 100% availability for the animal manure reduces the natural gas consumption by reformer from 2.373 to 1.605 million liters which means reduction of the natural gas consumption is 32.35%. The results conclude that H2 produced by livestock waste is dominating among available wastes. However, there is about 18% reduction in the Cost of Energy (COE), when 100% availability is considered for this type of waste.

Designing a toolset for assessing the organizational and technological inertia of energy consumption processes at enterprises

The object of this study is the assessment of the organizational and technological inertia of energy consumption processes at enterprises. The task to design effective toolset for such an assessment was tackled. The indicators for assessing the organizational and technological inertia of energy consumption processes at enterprises have been determined and systematized. The factors that influence the level of this inertia were highlighted. A method for decomposing the relative level of organizational and technological inertia of energy consumption processes has been developed. The level of organizational and technological inertia of the processes of natural gas consumption was assessed on the basis of a sample of enterprises. It has been established that this level is quite high. In particular, the duration of lag in the reduction of natural gas consumption, averaged over 2016–2021, ranged from 1.3 to 1.8 years. At the same time, the relative level of organizational and technological inertia of the processes of consumption of natural gas in terms of its natural volumes ranged from 36.5 % to 47.9 %. The empirical results are explained by the presence of significant obstacles to the implementation of organizational and technological measures to save natural gas. A feature of the designed toolset for assessing the organizational and technological inertia of energy consumption processes is that its use makes it possible to obtain a comprehensive and accurate assessment of the specified inertia. This toolset can be used by enterprises of all types of economic activity in assessing the reserves for reducing the organizational and technological inertia of energy consumption. In addition, the designed tools can be used by state authorities and local governments in the formation of strategies for energy-saving economic development

Development of hardware and software support of computer-integrated technology of complex of secondary condensation of ammonia production

The object of research is the technological complex of secondary condensation (TCSC) and the control system of a typical ammonia synthesis unit of the AM-1360 series. The analysis of the conditions of its functioning and hardware and technological design was carried out. The coordinates of the control vector are determined. The features of the proposed functional diagram and the necessary algorithmic software for the computer-integrated control technology of the TCSC with a correction subsystem for decision-making under uncertainty are established. The implementation of the proposed solutions is complicated by the use of the information and control complex TDC-300 (USA) with closed-type software installed on the existing ammonia synthesis units. The need for such a control complex to implement a decision-making subsystem under conditions of uncertainty is shown to supplement the existing control system with hardware and software of an «open» type. A computer-integrated TCSC technology based on a three-level hierarchical structure has been created. The implementation of the zero and first levels of such a structure form single software and hardware complex consisting of a programmable logic controller and an automated operator's workplace based on an industrial computer with installed software. A software implementation of decision-making on the correction of the coordinates of the control vector by additional hardware and software based on the VIPA logic controller and the Zenon SCADA system was made. A scheme of network information flows has been implemented, which illustrates the functioning of the decision-making correction subsystem in the general structure of the TCSC computer-integrated control technology. Implementation of the developed system allows, under the existing uncertainties, to reduce the secondary condensation temperature by an average of 3 °C, which ensures an annual reduction in natural gas consumption by 1 million nm3. The proposed approach to the possibility of combining «open» and «closed» type hardware and software can be applied in other industries.

ASHRAY: Enhancing Water-usage Comfort in Developing Regions using Data-driven IoT Retrofits

In developing countries, majority of the households use overhead water tanks to have running water. These water tanks are exposed to the elements, which usually render the tap water uncomfortable to use, given the extreme subtropical weather conditions. Externally weatherproofing these tanks to maintain the groundwater temperature is short-lived, and only results in a marginal (0.5°C–1°C) improvement in tap water temperature. We propose Ashray , an IoT-inspired, intelligent system to minimize the exposure of water to the elements thereby maintaining its temperature close to that of the groundwater. Ashray learns the water demand patterns of a household and pumps water into the overhead tank only when necessary. The predictive, machine learning based, approach of Ashray improves water comfort by up to 8°C in summers and 3°C in winters, on average. Ashray is retrofitted into existing infrastructure with a hardware prototyping cost of $27, whereas it can save up to 16% on water heating costs, through reduction in natural gas consumption, by leveraging groundwater temperature. Moreover, we also consider a transiently-powered Ashray , which uses the energy harvested from the ambient environment, and propose an intermittent data pipeline to improve its prediction accuracy. The transiently-powered Ashray is suitable for long-term deployment, requires minimal maintenance and delivers approximately the same performance. Ashray has the potential to improve the thermal comfort and reduce energy costs for millions of households in developing countries.

ANALYSIS OF DIRECTIONS OF ENERGY SAVING POTENTIAL MANAGEMENT IN INDUSTRIAL PRODUCTION OF UKRAINE

Annotation. The aim of the work is to substantiate the areas of energy saving potential management of the industrial sector of the national economy. To achieve this goal, the methods of economic and mathematical modeling were used and a function was obtained that reflects the relationship of structural changes with the energy intensity of Ukraine's GDP. The assessment of the energy saving potential in Ukrainian industry by structural and technical factors allowed to prove a positive impact not only on the energy efficiency of industrial production, but also to determine the potential reduction of energy intensity of the country's GDP by supply of primary energy resources. Thus, structural shifts in the economy of Ukraine towards reducing the share of industrial production and increasing the share of services in the field of information technology, scientific and technical activities, lower rates of primary energy supply compared to GDP, it is possible to achieve target energy efficiency targets by 2030. The result of the research is to determine the potential reduction of energy intensity of the country's GDP by the supply of primary energy resources as a result of structural and technical changes (reduction of industrial production and increasing the share of services in information technology, science and technology, lower primary energy supply GDP, modernization of electricity, gas, steam and air conditioning technologies by reducing coal consumption). The scientific novelty of the study is to improve methods of analysis and forecasting of energy saving potential in industrial production of Ukraine. Improving the technical characteristics of industrial production will significantly reduce the share of coal and natural gas savings. In the sectoral context, the greatest potential for energy savings in industry is to modernize technologies for the supply of electricity, gas, steam and air conditioning by reducing coal consumption. A significant share of potential energy saving technologies is made by the processing industry mainly due to the reduction of natural gas consumption at metallurgical enterprises. The practical significance of the study is determined by further development of appropriate management measures that can affect energy efficiency of Ukraine's industrial sector.

Asymmetric Effects of Consumption of Renewable and Nonrenewable Energies on Human Development Index

This paper investigates the asymmetric short and long-run effects of the consumption of renewable (biomass and biogas and hydro) and nonrenewable energies (oil and natural gas) on the human development index, a proxy of sustainable development. Reaching this goal, the study uses NARDL (Nonlinear Autoregressive Distributive Lag Model) model with yearly data from 1990 to 2018. It also investigates the effect of nuclear sanction on the human development index. The results show consumption of hydro energies has no effect on the human development index neither in the short-run nor in the long run while the consumption of biomass and biogas positively affects the human development index. A reduction in crude oil consumption negatively affects the human development index in both the short and the long run. However, a unit reduction in natural gas consumption reduces the human development index in both the short and long run. The results also indicate natural gas has by far a stronger effect on the human development index that may be due to the abundance of this resource in Iran. Human development index has not significantly influenced by sanction.

COMPARATIVE CHARACTERISTICS OF UTILIZATION INSTALLATIONS OF FLUE GASES OF BOILERS WITH HUMIDIFICATION OF AIR

Reduction of natural gas consumption in industrial and municipal heat power engineering in particular industrial CHP`s (combined heat and power plant) and boilers plants can be achieved by increasing its utilization rate. It is known that the smoke gas temperature in the outlet of many steam and hot water boilers exceeds 140 oC, which is also characterized by increased heat loss with flue gases and low efficiency of these units. The use of utilization installations of flue gases for deep cooling of combustion products below the dew point temperature will increase their efficiency and in general increase the COP (coefficient of performance) of the boiler and reduce the consumption of natural gas. Condensing contact mixing heat exchangers or film heat exchangers or surface heat exchangers can be used for these purposes. In last years the requirements to the operation of boilers are increasing for reducing emissions of nitrogen oxides that are harmful to the environment. One of the effective methods of reducing nitrogen oxides is humidification of air, for example, in contact air heaters. The methods and results of calculations of energy and ecological efficiency of heat utilization installations with KTAN (contact heat exchanger with active header) utilizer and KTAN air heater, ecologically clean installation and surface utilizers-heaters are given in the work. Calculations were performed for units installed in a water-heating boiler house in Kyiv with a KV GM-10 (water-heating boiler that burns gas and fuel-oil) water-heating boiler. It is shown that the surface utilize heater unit is characterized by the highest indicators of energy and environmental efficiency. It has the highest power of utilized heat (2312 kW) and the lowest operating and consolidated costs (25950 and 119140 UAH / year, respectively), as well as the lowest emissions of nitrogen oxides with flue gases (0.06 g / s). Further on these indicators there is the ecologically pure heat utilization installation, and the installation with KTAN-utilizer - KTAN - air heater is characterized by the lowest ecological and energy efficiency and at the same time ecologically pure installation has the same ecological efficiency.

OPTIMIZATION OF CEMENTATION TECHNOLOGY OF TRACK LINK SLEEVES IN THE ATMOSPHERE METHANE-AIR MIXTURE

New three- and four-cycle experimental cementation regimes for a layer thickness of up to 4.0 mm in an atmosphere of natural gas with air additives have been developed. Rational schemes for adding air to the atmosphere of methane for carburizing in shaft furnaces at different thicknesses of the hardened layer have been determined. Industrial testing of new modes has shown the possibility of reducing the total duration of the cementation process by 25%; significant reduction in energy consumption for heating furnaces and reduction of natural gas consumption for one carburizing mode by 35%.

HIGH TEMPERATURE COMPACT CERAMIC REGENERATIVE HEAT EXCHANGER

The subject of the research is the high-temperature compact ceramic heat exchanger of a regenerative type with a honeycomb structure. In relation to high-temperature processes of basalt smelting and glass melting, the possibility of its application in a system of high-temperature air combustion is considered. It is noted that heating of the air pursues both energy goal – reduction of natural gas consumption, and technological goal – increasing the amount of free oxygen in the basalt processing zone. The methods of determining the transient temperature field in the wall of the solid heat-storing material of the regenerator and the operating time of the heat exchanger from the condition of ensuring the permissible surface temperature of the heat regenerator are given. It is established that for the range of the Fourier number Fo≤2.5, it is possible not to take into account the temperature distribution in the wall of the solid heat-storing material of the regenerator and to operate with its average temperature. Features of compact ceramic regenerative heat exchangers are given – heat exchanger efficiency, heat recovery coefficient, number of transfer units, power – as applied to the conditions of the heat engineering process. The heat exchanger efficiency is confirmed. The operating time of the heat exchanger and its effect on the surface temperature of the solid heat-storing material are determined. It is shown that in relation to the conditions of the basalt melting and glass melting processes, the material of the regenerative heat exchanger – mullite – is not an optimal solution. Only for one of the considered variants of the technological process, the surface temperature of the regenerative heat exchanger was lower than the permissible temperature of prolonged use of mullite. In other cases, the resulting temperature of the regenerator exceeded the permissible value of long-term use. It is advisable to use a material with a permissible temperature of application of 1525 °C and above as of the solid heat-storing material of the regenerator. Testing of the results of the research was carried out on pilot industrial samples of bath melting furnaces equipped with HiTAC (high-temperature air combustion system).

Changes in Energy Consumption, Economic Growth and Aspirations for Energy Independence: Sectoral Analysis of Uses of Natural Gas in Ukrainian Economy

The main objective of the research is to assess the ability of the Ukrainian economy and its individual industries to ensure, in the conditions of economic growth, a stable reduction of natural gas consumption and, consequently, to reduce dependence on its imports. Six types of relationships were identified between the change in sectoral added value and the change in the consumption of certain energy resources, in particular natural gas. The conditions are established under which the growth of sectoral added value is accompanied by a decrease in the consumption of certain energy resources. The index of sectoral efficiency of the use of certain energy resources was proposed and a model of the decomposition of the growth rate of this indicator was constructed. Quantitative indicators of measuring economic barriers on the way to introduction of energy-saving technologies are presented. Conditions under which economic growth is accompanied by a decrease in the level of dependence of the economy on imports of energy resources are modeled. The dynamics of natural gas consumption by sectors of the Ukrainian economy is analyzed. It is proved that reduction of natural gas consumption due to increased energy efficiency occurs mainly in industries with an average value of share of the cost of purchasing this energy in the total operating expenses. An estimation is undertaken of the possibility of achieving independence of the Ukrainian economy from the import of natural gas in different scenarios of changing main parameters that determine the probability of such an achievement.

A practical artificial intelligence-based approach for predictive control in commercial and institutional buildings

This paper presents a methodology for the development and implementation of Model Predictive Control (MPC) in institutional buildings. This methodology relies on Artificial Intelligence (AI) for model development. An appropriate control-oriented model is a critical component in MPC; model development is no easy task, and it often requires significant technical expertise, effort and time, along with a substantial amount of information. AI techniques enable rapid development and calibration of models using a limited amount of information (i.e. measurements of few variables) while achieving relatively high accuracy. In this study, the MPC algorithm targets the reduction of natural gas consumption by optimizing the transition between night set-back and daytime indoor air set-point values as a function of the expected weather. This MPC strategy was implemented in an institutional building in Varennes (QC), Canada, during the heating season 2018–19. A significantly better performance was achieved when compared with “business as usual” control strategies: the natural gas consumption and greenhouse gas (GHG) emissions were reduced by approximately 22%, and the building heating demand by 4.3%. The proposed strategy is scalable and can be replicated in other buildings.

КОМПЛЕКСНЕ ОЦІНЮВАННЯ ЕКОНОМІЧНОЇ ТА ЕКОЛОГО-ЕНЕРГЕТИЧНОЇ ЕФЕКТИВНОСТІ ВИКОРИСТАННЯ ТЕХНОЛОГІЙ «РОЗУМНИЙ БУДИНОК» В СИСТЕМАХ ОПАЛЕННЯ ЗАКЛАДІВ ОСВІТИ

The results of a comprehensive assessment of the economic, environmental and energy effects of using the "smart home" technology to control the heating modes of a natural object - the communal institution "Kharkiv Palace of Children's and Youth Creativity of the Kharkiv City Council of the Kharkiv Region" (CI KPCYC) are presented. The following criteria were considered as efficiency criteria: energy effect - absolute and relative reduction of monthly and annual heat consumption; environmental effect - reduction of monthly and annual fuel consumption by the building's heat supply system, reduction of greenhouse gas emissions into the atmosphere — CO2 and pollutants — NOx in the production of heat energy; economic effect - monthly and annual reduction of fees for the use of heat and fuel by the object of research. A method for the integrated assessment of the efficiency of energy-saving measures has been created, which makes it possible to determine the indicators of energy, environmental and economic effects. In order to improve the environmental and energy and economic efficiency of the heat consumption system of a full-scale facility, it is proposed to use the “smart home” technology to control the modes of space heating, which provides for the introduction of the HERZ Smart Comfort system or its equivalent for the automated regulation of the thermal conditions of the building premises. in the comfort of providing thermal energy. For the natural object - the building of the CI KPCYC, the annual effect from the “smart” control of the heating system is estimated: energy: energy savings: 130.3 Gcal or 7.0%; ecological: reduction of natural gas consumption - 16.5 thousand m3, reduction of CO2 and NOx emissions into the atmosphere - 32.0 tons and 0.035 tons, respectively; economic: reduction of payment for heating - 249.5 thousand UAH.

Energy and environmental analysis of a natural gas pressure reduction station equipped with turboexpander, solar collector, and storage tank

The pressure of natural gas in the transmission pipelines is high, and it is not suitable for urban consumptions. Therefore, it should be decreased to a certain lower amount in the pressure reduction stations near the urban area by the pressure reducing valves. Recently, for recovering the energy losses in these valves and generating electricity, turboexpanders are utilized. However, the pressure decrease in the turboexpander results in a sudden decrease in temperature, which leads to the formation of hydrates. To prevent the hydrate formation, preheating is required, which is conventionally done by a line heater. In this study, the required energy for preheating the natural gas entering the station is supplied from the solar energy and an auxiliary line heater for a case study of Mashhad city (Iran). Parabolic trough thermal collectors are used for the absorption of the solar radiant energy. The collector was modeled through one-dimensional implicit finite-difference method and using discretization of energy balance equation between the working fluid, the absorbent pipe, and the glass envelope. The reduction in natural gas consumption and the produced CO2 emission are computed for the pressure reduction station with a thermal collector and a storage tank. The results reveal that the presence of the thermal collector and the storage tank reduces the consumption of fuel and consequently the generation of pollutant about 90%.

Transpired solar collectors in building service engineering: Combined system operation and special applications

One of the easiest ways to integrate renewable sources of energy into the heat producing system of a building is the application of transpired solar collectors. They are widespread in North America, where air heating is a common heating alternative, but they are gaining bigger share in the European solar thermal market nowadays. Their simple construction, maintenance-free operation and high working efficiency result in low capital and operating costs. The combination of TSC with other system elements results in additional benefits. Preheating the combustion air of large-scale boilers results in the increase of boiler efficiency and thus the reduction of natural gas consumption and CO2 emission. Whether to choose TSC or heat recovery unit for a certain air conditioning system has to be investigated by examining efficiency-influencing factors of both systems. Besides solar air heating, transpired solar air collectors can reduce the cooling demand on a building. Roof ventilation and nocturnal radiant cooling are two alternatives, which are being presented in the current paper.