scholarly journals Comparison of Single- and Multipipe Earth-to-Air Heat Exchangers in Terms of Energy Gains and Electricity Consumption: A Case Study for the Temperate Climate of Central Europe

Energies ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 8217
Author(s):  
Łukasz Amanowicz ◽  
Janusz Wojtkowiak
Keyword(s):  
Heat Exchangers ◽  
Experimental Studies ◽  
Electric Energy ◽  
Electricity Consumption ◽  
User Preferences ◽  
Temperate Climate ◽  
Pressure Losses ◽  
Electric Energy Consumption ◽  
Energy Gains ◽  
Single Pipe

Earth-to-air heat exchangers (EAHEs) can be used in the ventilation systems of various types of buildings. Multipipe structures can be found in large-volume buildings, yet scientific analysis of such systems is rare. Annual energy gains and electricity consumption for equivalent single-pipe and multipipe systems are typically not available. This paper bridges this gap, presenting the results of experimental studies on pressure losses in three-, five- and seven-pipe EAHEs and analysis for the annual energy gains and electric energy consumption as compared to a single-pipe exchanger. The results showed that the multipipe EAHE can be successfully replaced by a single-pipe structure with the same thermal performance and similar pressure losses if a tube with the appropriate diameter is used. However, multipipe heat exchangers can also use pipes of larger diameter (manifolds and/or branches), which improves their energy efficiency and may then make them more advantageous than single-pipe structures. From this reason, ultimately, the final selection of exchanger geometry should take into account economic and environmental issues and also user preferences and their importance in the hierarchy.

scholarly journals Parallel Evolutionary Biclustering of Short-term Electric Energy Consumption

2021 ◽  
Author(s):  
Diego P. Pinto-Roa ◽  
Hernán Medina ◽  
Federico Román ◽  
Miguel García-Torres ◽  
Federico Divina ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Electric Energy ◽  
Electricity Consumption ◽  
Search Space ◽  
Consumption Pattern ◽  
Electric Energy Consumption ◽  
System A ◽  
Time Period ◽  
Computation Scheme ◽  
Significant Patterns

The discovery and description of patterns in electric energy consumption time series is fundamental for timely management of the system. A bicluster describes a subset of observation points in a time period in which a consumption pattern occurs as abrupt changes or instabilities homogeneously. Nevertheless, the pattern detection complexity increases with the number of observation points and samples of the study period. In this context, current bi-clustering techniques may not detect significant patterns given the increased search space. This study develops a parallel evolutionary computation scheme to find biclusters in electric energy. Numerical simulations show the benefits of the proposed approach, discovering significantly more electricity consumption patterns compared to a state-of-the-art non-parallel competitive algorithm.

scholarly journals Electric energy consumption of milking process on some Finnish dairy farms

2017 ◽  
Vol 26 (3) ◽  
Author(s):  
Mari Rajaniemi ◽  
Tapani Jokiniemi ◽  
Laura Alakukku ◽  
Jukka Ahokas
Keyword(s):  
Energy Consumption ◽  
Energy Savings ◽  
Electric Energy ◽  
Cooling Water ◽  
Electricity Consumption ◽  
Dairy Farms ◽  
Energy Costs ◽  
Heating Systems ◽  
Electric Energy Consumption ◽  
Energy Saving Potential

The aim of this study was to examine the electric energy consumption of milking process on dairy farms and to evaluate the methods to improve the energy efficiency. The electricity consumption of the milking process was measured on three dairy farms in Southern Finland, and it varied between 37–62 Wh kg-1 milk.  The largest energy saving potential was identified in milk cooling and the heating of cleaning water. Even simple methods, such as placing the condenser of the refrigeration system outside, may reduce the energy consumption of milk cooling by 30%. Efficient milk pre-cooling can reduce the energy consumption of the whole milking process by more than 25%. Even larger energy savings are possible with a sophisticated milk cooling – water heating systems. It was concluded that there is a significant potential to reduce the energy consumption and energy costs of the milking process, and thus to improve the profitability and sustainability of the sector at the same time.

MATHEMATICAL MODELS FOR MONITORING AND CONTROL OF ELECTRIC ENERGY CONSUMPTION WITH ACCOUNT OF THE SEASONAL FACTOR

2017 ◽  
Vol 11 (5) ◽  
pp. 133-140 ◽  
Author(s):  
Сергей Лавренченко ◽  
Sergey Lavrenchenko ◽  
Людмила Згонник ◽  
Lyudmila Zgonnik ◽  
Инна Гладская ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Power Consumption ◽  
Electric Energy ◽  
Electricity Consumption ◽  
Daily Basis ◽  
Monitoring And Control ◽  
Theoretical Level ◽  
Electric Energy Consumption ◽  
Energy Meter ◽  
Seasonal Factor

The article proposes a method for predicting the daily energy consumption level for every day of a whole year, taking into account the season-al factor, based on only twelve actual power consumption data by the months of the year. Then a mathematical model is developed for moni-toring and controlling the level of electricity consumption on a daily basis, taking into account the seasonal factor. The model is consistent with a common model for the length of daylight (in hours). In addition, on the basis of this model, a method of monitoring and diagnostics of electricity consumption is presented, which will allow users to monitor the level of power consumption and be timely notified of any deviations from the theoretical level. Finally, this method gives rise to the operational principle for a proposed device, a smart energy meter, for detecting suspicious deviations from the theoretical level. The device will help timely detect over-consumption (or under-consumption) of electricity in order to take preventive measures. The proposed method consists of the following steps: (1) choice of a function to model the level of electricity consumption (theoretical calculated level), (2) choice of a tubular control neighborhood of the graph of the model function, (3) choice of a criterion on when the smart energy meter should notify the user of an unexpected deviation from the theoretical level in the case of exit from the tubular control neighborhood.

scholarly journals Bagging Ensemble of Multilayer Perceptrons for Missing Electricity Consumption Data Imputation

Sensors ◽  
2020 ◽  
Vol 20 (6) ◽  
pp. 1772 ◽  
Author(s):  
Seungwon Jung ◽  
Jihoon Moon ◽  
Sungwoo Park ◽  
Seungmin Rho ◽  
Sung Wook Baik ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Energy Management ◽  
Missing Values ◽  
Electric Energy ◽  
Electricity Consumption ◽  
Multilayer Perceptrons ◽  
Imputation Methods ◽  
Electric Energy Consumption ◽  
Consumption Data ◽  
Bagging Ensemble

For efficient and effective energy management, accurate energy consumption forecasting is required in energy management systems (EMSs). Recently, several artificial intelligence-based techniques have been proposed for accurate electric load forecasting; moreover, perfect energy consumption data are critical for the prediction. However, owing to diverse reasons, such as device malfunctions and signal transmission errors, missing data are frequently observed in the actual data. Previously, many imputation methods have been proposed to compensate for missing values; however, these methods have achieved limited success in imputing electric energy consumption data because the period of data missing is long and the dependency on historical data is high. In this study, we propose a novel missing-value imputation scheme for electricity consumption data. The proposed scheme uses a bagging ensemble of multilayer perceptrons (MLPs), called softmax ensemble network, wherein the ensemble weight of each MLP is determined by a softmax function. This ensemble network learns electric energy consumption data with explanatory variables and imputes missing values in this data. To evaluate the performance of our scheme, we performed diverse experiments on real electric energy consumption data and confirmed that the proposed scheme can deliver superior performance compared to other imputation methods.

scholarly journals The Impact of the COVID-19 Pandemic on Electricity Consumption and Economic Growth in Romania

Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2394
Author(s):  
Georgeta Soava ◽  
Anca Mehedintu ◽  
Mihaela Sterpu ◽  
Eugenia Grecu
Keyword(s):  
Economic Growth ◽  
Linear Regression ◽  
Regression Model ◽  
Linear Regression Model ◽  
Negative Impact ◽  
Electric Energy ◽  
Electricity Consumption ◽  
Electric Energy Consumption ◽  
The One ◽  
The Impact

This paper analyzes the impact of the COVID-19 pandemic on economic growth and electricity consumption and investigates the hypothesis of the influence of this consumption on the gross domestic product (GDP) for Romania. Using time series on monthly electricity consumption and quarterly GDP and a multi-linear regression model, we performed an analysis of the evolution of these indicators for 2007–2020, a comparison between their behavior during the financial crisis vs. COVID-19 crisis, and empirically explore the relationships between GDP and electricity consumption or some of its components. The results of the analysis confirm that the shock of declining activity due to the COVID-19 pandemic had a severe negative impact on electric energy consumption and GDP in the first half of 2020, followed by a slight recovery. By using a linear regression model, long-term relationships between GDP and domestic and non-household electricity consumptions were found. The empirically estimated elasticity coefficients confirm the more important impact of non-household electricity consumption on GDP compared to the one of domestic electricity consumption. In the context of the COVID-19 pandemic, the results of the study could be useful for optimizing energy and economic growth policies at the national and European levels.

scholarly journals Calculation of specific rates of the electric energy consumption at frequency regulation of electric drives: A case study of pumping stations

2021 ◽  
Vol 939 (1) ◽  
pp. 012001
Author(s):  
T Kamalov ◽  
A Isakov ◽  
A Shavazov ◽  
A Elmuratova ◽  
B Tukhtamishev
Keyword(s):  
Energy Consumption ◽  
Experimental Studies ◽  
Electric Energy ◽  
Electrical Energy ◽  
Design Parameters ◽  
Frequency Regulation ◽  
Electric Drives ◽  
Electric Energy Consumption ◽  
Pumping Stations ◽  
Pumping Units

Abstract The issues of developing a methodology for calculating the specific rates of electrical energy consumption during frequency regulation of electric drives of pumping stations are considered. When calculating specific consumption rates, experimental studies were carried out at the Chirchik pumping station. When developing the methodology, technological, design parameters, water consumption, as well as the total capacity of pumping units based on frequency-controlled electric drives are taken into account. At the same time, the characteristics of the main parameters that must be taken into account when choosing variable frequency drives for pumping units are determined.

scholarly journals Analytical Treatment of Forecasts of Electric Energy Consumption in Latvia

2014 ◽  
Vol 51 (3) ◽  
pp. 3-14
Author(s):  
M. Balodis ◽  
V. Gavars ◽  
J. Andersons
Keyword(s):  
Energy Consumption ◽  
Structural Changes ◽  
Electric Energy ◽  
Electricity Consumption ◽  
Time Span ◽  
Analytical Treatment ◽  
East European ◽  
Electric Energy Consumption ◽  
West Central ◽  
Specific Electricity Consumption

Abstract In the paper, the changes in electric energy consumption are analyzed as associated with structural changes in the Latvian economy of postsocialistic period. To the analysis, a particular approach is applied, which consists in comparison of the basic and specific electricity consumption indices in West-, Central-, and East-European states for the time span of 1990-2010, with differences and tendencies of changes revealed. Tendencies of the type are determined for the electric energy consumption in Latvia, and recommendations are given for the use of such indices in the relevant forecasts.

scholarly journals Prospects of the Russian Coal Industry in the Conditions of Transition to a New Energy Pattern

2020 ◽  
Vol 9 (4) ◽  
pp. 1831-1835
Keyword(s):  
Energy Production ◽  
Electric Energy ◽  
Electricity Consumption ◽  
Coal Industry ◽  
Electric Energy Consumption ◽  
The World ◽  
New Energy ◽  
Forecast Models ◽  
To Come ◽  
Competitive Products

The article analyzes the prospects for changes in the volume of exports of Russian coal due to the reduction of its consumption for energy production by the importing countries. The importance of Russian power generating coal for the energy supply to the world as a whole and to individual importing regions in particular is shown. It is justified that a radical and abrupt refusal to use coal as an energy source in the next few years would hardly be possible because the per capita and the total electric energy consumption has been growing all over the world. To a large extent, this is due to the increase in the number of data centers around the world, which centers do not yet have enough “green” sources of energy to ensure the uninterrupted operation thereof. Therefore, coal exports from Russia to the European countries, China and DPRK will continue to grow in the years to come; this is confirmed by the forecast models built by the authors, which models consider changes in the coal and electricity consumption by major importers. By the time the conditions are ensured for the majority of countries in the world to abandon coal as a source of electricity in order to stop air pollution, Russia will need to find opportunities for its alternative use, an example of which would be the creation and development of production of competitive products of the coal chemical industry.

scholarly journals EDITORIAL

2015 ◽  
Vol 14 (1) ◽  
pp. 02 ◽  
Author(s):  
A. B. Mariano
Keyword(s):  
Fossil Fuels ◽  
Waste Heat ◽  
Electric Energy ◽  
Electricity Consumption ◽  
Global Solutions ◽  
Heat Pumps ◽  
Thermal Engineering ◽  
Simulation And Optimization ◽  
Electric Energy Consumption ◽  
Biotechnological Processes

The need for diversification of the global energy grid is present in the speeches of most governments, the motivation of scientists and the perception of a growing segment of the population. Even so, the dependence on non-renewable fuels, such as fossil fuels, has been increasing progressively due to the rapid global growth, rising consumption and increasing purchasing power of the population. Besides searching global solutions to resolve the energy quest, efforts must be directed to short-term actions, taking advantage of the available scientific and technological knowledge to improve the performance of existing systems and in use today. Improving the efficiency of cooling systems, which are responsible for much of the world electricity consumption through intelligent control of compressors can reduce up to 50% electricity consumption, and thus provide economic and strategic advantages to countries that encourage this type of initiative. Likewise, the reduction of electricity for domestic heating or showering can be obtained by waste heat recovery, solar heating or the use of heat pumps with immersed condensers, among others, contributing to the reduction of electric energy consumption. A challenge to be overcome is the popularization of such technologies in the form of final product at affordable costs. Also, for popular use, it is the important the interest of nation leaders in order to drive the use of those technologies through tax incentives and public policies. Other advances could be achieved by the use and improvement of biotechnological processes, coupling the treatment of emissions and effluents to the production of biofuels, as well as high aggregated value products. Through exergy analysis, thermoeconomics, mathematical modeling, simulation and optimization, thermal engineering is able to contribute to the efficient coupling of such different biotechnological processes and contribute to decreasing dependence on fossil fuels.

Theoretical and Experimental Analyses of Energy Efficient Air Dehumidification Systems for Tropical Climates Using Membrane Technology

2011 ◽  
Author(s):  
Zaw Khin ◽  
Kim Choon Ng
Keyword(s):  
Water Content ◽  
Air Conditioning ◽  
Electric Energy ◽  
Electricity Consumption ◽  
Membrane System ◽  
Ambient Air ◽  
Electric Energy Consumption ◽  
Set Up ◽  
Comsol Simulation ◽  
Air Conditioning Systems

This paper presents the analytical and experimental analysis of a membrane based air-dehumidification system for handling the latent loads efficiently. This is important for tropical countries like Singapore where the humidity content of ambient air is high and therefore, air conditioning systems need to handle large latent load. A detailed COMSOL simulation model was set-up in order to simulate the water diffusion through the membrane. Experimental results from a real size membrane dehumidification unit are used to validate the mathematical model. Our investigations show that the moisture content of ambient air may be reduced by more than 5 g per kg of air if the dehumidification process is driven by the gradient between the water content of ambient air and the water content of exhaust air form air-conditioned spaces. With the exception of low electricity requirement for air transport, there is no electric energy consumption in the system. Therefore, the membrane system discussed in this paper is an efficient and alternative way of air dehumidification for air conditioning applications, potentially reducing the electricity consumption of air conditioning system in tropics.

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