Minimizing energy consumption in reverse osmosis desalination using renewable energy sources: A review

In this contemporary era, environmental problems spread at different levels in all countries of the world. Economic growth does not just depend on prioritizing the environment or improving the environmental situation. If the foreign direct investment is directed to the polluting industries, they will increase pollution and damage the environment. The purpose of the study is to consider the relationship between foreign direct investment in Kazakhstan and Uzbekistan and economic growth and renewable energy consumption. The study is based on data obtained from 1992 to 2018. The results show that there is a two-way link between foreign direct investment and renewable energy consumption in the considered two countries. The Granger causality test approach is applied to explore the causal relationship between the variables. The Johansen co-integration test approach is also employed to test for a relationship. The empirical results verify the existence of co-integration between the series. The main factors influencing renewable energy are economic growth and electricity consumption. To reduce dependence on fuel-based energy sources, Kazakhstan and Uzbekistan need to attract energy to renewable energy sources and implement energy efficiency based on rapid progress. This is because renewable energy sources play the role of an engine that stimulates the production process in the economy for all countries.

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Changes in Energy Consumption in Agriculture in the EU Countries

Energies ◽

10.3390/en14061570 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1570

Author(s):

Tomasz Rokicki ◽

Aleksandra Perkowska ◽

Bogdan Klepacki ◽

Piotr Bórawski ◽

Aneta Bełdycka-Bórawska ◽

...

Keyword(s):

European Union ◽

Renewable Energy ◽

Energy Consumption ◽

Correlation Coefficient ◽

Renewable Energy Sources ◽

Energy Sources ◽

The European Union ◽

Eu Countries ◽

Research Hypothesis ◽

The Eu

The paper’s main purpose was to identify and present the current situation and changes in energy consumption in agriculture in the European Union (EU) countries. The specific objectives were the determination of the degree of concentration of energy consumption in agriculture in the EU countries, showing the directions of their changes, types of energy used, and changes in this respect, establishing the correlation between energy consumption and changes in the economic and agricultural situation in the EU countries. All member states of the European Union were deliberately selected for research on 31 December 2018 (28 countries). The research period covered the years 2005–2018. The sources of materials were the literature on the subject, and data from Eurostat. Descriptive, tabular, and graphical methods were used to analyze and present materials, dynamics indicators with a stable base, Gini concentration coefficient, concentration analysis using the Lorenz curve, coefficient of variation, Kendall’s tau correlation coefficient, and Spearman’s rank correlation coefficient. A high concentration of energy consumption in agriculture was found in several EU countries, the largest in countries with the largest agricultural sector, i.e., France and Poland. There were practically no changes in the concentration level. Only in the case of renewable energy, a gradual decrease in concentration was visible. More and more countries developed technologies that allow the use of this type of energy. However, the EU countries differed in terms of the structure of the energy sources used. The majority of the basis was liquid fuels, while stable and gaseous fuels were abandoned in favor of electricity and renewable sources—according to which, in the EU countries, the research hypothesis was confirmed: a gradual diversification of energy sources used in agriculture, with a systematic increase in the importance of renewable energy sources. The second research hypothesis was also confirmed, according to which the increase in the consumption of renewable energy in agriculture is closely related to the economy’s parameters. The use of renewable energy is necessary and results from concern for the natural environment. Therefore, economic factors may have a smaller impact.

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Utilization of Renewable Energy Sources in Road Transport in EU Countries—TOPSIS Results

Energies ◽

10.3390/en14227457 ◽

2021 ◽

Vol 14 (22) ◽

pp. 7457

Author(s):

Joanna Kisielińska ◽

Monika Roman ◽

Piotr Pietrzak ◽

Michał Roman ◽

Katarzyna Łukasiewicz ◽

...

Keyword(s):

Renewable Energy ◽

Energy Consumption ◽

Renewable Energy Sources ◽

Road Transport ◽

Energy Sources ◽

Topsis Method ◽

Total Energy Consumption ◽

Eu Countries ◽

Relative Closeness ◽

The Status

The primary aim of this study was to assess and compare EU countries in terms of the use of renewable energy sources in road transport. The following research tasks were undertaken to realize this aim: (1) a review of the literature concerning the negative externalities in road transport, the concept of sustainable development, and legal regulations referring to the utilization of renewable energy sources; (2) presentation of changes in energy consumption (both traditional and renewable) in road transport in EU countries in the years 2008–2019; and (3) identification of leaders among the EU countries in terms of consumption of renewable energy sources in road transport. The aim and tasks were realized using the literature review and TOPSIS method as well as descriptive, tabular, and graphic methods. The analysis was conducted for 28 EU countries according to the status for 2019. The period of 2008–2019 was investigated. Sources of materials included literature on the subject and Eurostat data. Although renewable energy sources accounted for as little as 6% of total energy consumption in road transport in EU countries in 2019, this is a significant topical issue. It results from the direction in which changes need to be implemented in terms of energy generation in this area of human activity. It turned out that blended biodiesel and blended biogasoline were the most commonly used fuels originating from renewable sources. The application of the TOPSIS method resulted in the identification of five groups of EU member countries, which differed in terms of the degree of utilization of renewable energy sources in road transport. Luxemburg, Sweden, and Austria were leaders in this respect. In turn, Malta, Estonia, and Croatia were characterized by very low consumption of renewable energy. The greatest progress in the utilization of renewable energy sources in road transport was recorded in Sweden, Finland, and Bulgaria (changes in the relative closeness to the ideal solution from 0.15 to 0.27), while the greatest reduction in relation to other countries was observed in Austria, Germany, and Lithuania (changes from −0.35 to −0.22).

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Energy benchmarking in educational buildings in the city of Kragujevac - possibilities for energy efficiency improvement

Serbian Journal of Electrical Engineering ◽

10.2298/sjee2101095r ◽

2021 ◽

Vol 18 (1) ◽

pp. 95-114

Author(s):

Ana Radojevic ◽

Danijela Nikolic ◽

Jasna Radulovic ◽

Jasmina Skerlic

Keyword(s):

Energy Efficiency ◽

Renewable Energy ◽

Energy Consumption ◽

Co2 Emissions ◽

Renewable Energy Sources ◽

Electricity Consumption ◽

Energy Sources ◽

Efficiency Improvement ◽

Energy Efficiency Improvement ◽

Energy Benchmarking

The implementation of energy efficiency measures and use of renewable energy sources in educational buildings can significantly contribute to reducing energy consumption, but also to CO2 emissions in the entire public sector. The paper shows the comparison of energy consumption indicators for 61 elementary school buildings which have previously been divided in 12 groups, according to the period of construction and size, based on the national typology called TABULA, as the first step of further study on how to use the renewable energy sources. The aim of this paper is to use the energy benchmarking process to select representative facilities which are suitable for applying renewable energy sources, for their further energy efficiency improvement. Indicators of annual specific electricity consumption and CO2 emissions per unit area [kWh/m2] and per user [kWh/user] were calculated. After that, from two groups (in which the highest electricity consumption and CO2 emissions are 68.37% and 74.53% of the total consumption/ emissions), one representative facility was selected.

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