Bibliometric Studies on Renewable Energy—Poland Compared to Other EU Countries
Abstract
:1. Introduction
1.1. Literature Review
1.2. Research Framework
- Step 1. Downloading and consolidation of the Scopus bibliographic data.
- Step 2. Data preprocessing; data cleaning and development of the thesaurus.
- Step 3. Quantitative analysis; summary statistics, Lorenz curves, and Gini coefficients.
- Step 4. Identification of scientific research topics related to renewable energy in Poland and in other EU countries.
2. Data and Methodology
2.1. Collection of Scopus Bibliographic Data
2.2. Data Preprocessing/Preparation
- incorrect records with truncated line endings were removed,
- entries [No abstract available] and [No author name available] were replaced with the Null value,
- square brackets and the text between them were deleted from the title field (these usually were the titles in authors’ national languages),
- typographic (curly) apostrophe characters (’ or ‘) were replaced by their straight equivalent ('),
- inverted comma characters (", “, and”) were deleted from the title field,
- both the dash character (–) and the hyphen character (-) appeared in article titles. In order to unify the titles in this aspect, a dash appearing in a date range was replaced by a hyphen; for other cases a dash was replaced by a hyphen including spaces around it,
- the last character of the title was examined; dots and special characters were deleted where appropriate,
- all duplicated records were removed.
2.3. Methods
- n—total number of journals in the RE bibliographic data obtained from Scopus,
- nj—number of journals in j-th class,
- xj—number of articles published by journals of j-th class.
- occurrence wi (or weight), which is defined as the number of documents containing the corresponding keyword, thus indicating its relevance,
- links ci, which denotes the total number of connections of the node, that is:
- total link strength TLSi, which is the sum of the link strengths for all links (connections outgoing from the node):
3. Results and Discussion
3.1. The Concentration of RE Publications
3.2. Thematic Analysis—Knowledge Maps of Bibliographic Data
- for 630 publications concerning Poland, the minimum number of occurrence was fixed to 10, which resulted in 88 phrases out of 3723,
- for 13,798 publications concerning other EU countries, the minimum number of occurrence was fixed to 50, which resulted in 411 phrases out of 46,755.
- bioenergy power generation: power plants (2012), biomass power (2012), crop production (2012), energy crops (2012), biomass (2013), biofuels (2013), forestry (2013), harvesting (2013), forest management (2013), biofuel production (2013),
- clean energy issue, climate topics, economic aspects: renewable energy resources (2014), biogas (2014), renewable energy (2015), solar energy (2015), photovoltaic cells (2016), alternative energy (2016), climate change (2015), global warming (2015), greenhouse gasses (2015), costs (2015), economics (2015), sustainable development (2015), commerce (2016), investments (2016),
- renewable energy storage technologies and areas related to energy transformation: solar power generation (2017), electric energy storage (2017), heat storage (2017), electric batteries (2017), electric vehicles (2017), renewable energy consumption (2018), energy transition (2019).
4. Conclusions
- (1)
- The selected time period of 17 years showed the relevance of RE topic in the last 4 years. A deeper insight into the statistics shows that there were 52% of the scientific publications on renewable energy regarding Poland and 33% referring to other EU countries.
- (2)
- Using the bibliometric analysis made it possible to identify leading journals on the publication market. The strong concentration of published articles around these journals is confirmed by the values of the Gini coefficient (greater than 0.5 for publications relating to both regions). The Energies journal was identified as the leader of recent years (2019–2021).
- (3)
- The obtained results revealed the researchers’ interest in similar topics in the last seventeen years (from 2005 to 2021) regarding both Poland and other EU countries, i.e., wind power and electricity generation from wind, bio-energy, environmental protection, climate change, solar energy in general, and energy transition. It is worth noting that the studies on hydropower, which are undertaken relatively often in other EU countries, are not very popular in works concerning Poland.
- (4)
- There are the following six hotspots (keywords with the highest occurrence and total link) in Poland articles: renewable energy resources (195; 769); energy policy (91; 460), renewable energy (89; 388), biomass (71; 307), sustainable development (53; 233), energy efficiency (53; 197), and the following six hotspots in other UE countries: renewable energy resources (2835; 16,660), renewable energy (2125; 11,642), energy policy (1354; 9195), wind power (1234; 6456), biofuels (1183; 6468); biomass (1150; 7422). The four terms in common confirm that the research course on RE in Europe is consistent.
- (5)
- The development history of the RE scientific research is divided into three phases. In Poland, the initial phase (till 2015) refers to biomass; the stable growth phase (2016–2018) refers to renewable energy resources and energy policy; the rapid development phase (2019–2021) refers to climate change and selected solar technologies. In other EU countries: the initial phase (until 2013) refers to biomass (during this period, most publications appeared in the Energy Policy journal); the slowdown growth phase (2014–2017) refers to subjects that seem to be in line with the EU Renewable Energy Directive (2009/28/EC) main resolutions (Renewable and Sustainable Energy Reviews is a dominant journal); rapid development phase (since 2018) refers to renewable energy storage technologies (Energies as a leading journal).
- (6)
- Interestingly, the result of the study shows a delay in the publication on RE topics for Poland in relation to other EU countries.
- (7)
- Research on renewable energy in Poland is relatively new; the first three articles registered in the Scopus database appeared in 2007, while in relation to other EU countries in 2005, there were 37 of them.
- (8)
- The analysis results show new scientific horizons of renewable energy in Europe but also the necessity to continue research on certain existing topics.
Author Contributions
Funding
Conflicts of Interest
References
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Authors (Year); Number of Citations | Period Region | Database Software | Literature Research Subject and Main Findings |
---|---|---|---|
Wuni et al. (2019); 85 | 1992–2018 The whole world | Database: Scopus Software: VOSviewer | Subject. Green building. Findings. In the world, 44% of countries are involved in green building research; US, UK, China, Canada, and Hong Kong play the most important role. Some areas still require further research, i.e., green building policies and rating tools, application of complexity theory and system dynamics, best practice framework for green buildings implementation, and assessment of green building financing initiatives [5]. |
Shi et al. (2021); 67 | 1992–2019, the whole world | Database: WoS Software: CiteSpace | Subject. Carbon footprint. Findings. The theme of carbon footprint research has changed from ecology and botany (before 2008) to international trade and household behaviors (after 2008). The research has shown a significant trend of diversification and interdisciplinary development since 2008 [6]. |
He et al. (2019); 41 | 1990–2013, US | Database: WoS Software: CiteSpace | Subject. Agricultural waste management, agricultural greenhouse gas emission reduction. Findings. US has a leading position in research regarding institutions and scholars. Major topics in the field are as follows: the low-carbon and energy utilization of agricultural waste, the influence of agricultural waste emissions, the material flow and energy flow of agricultural waste, the prevention and control of agricultural waste pollution [7]. |
Andreo-Martínez et al. (2020); 33 | 2001–2019, the whole world | Database: WoS Software: MS Excel, BibExcel, VOSviewer | Subject. Biodiesel production. Findings. The first rank in the field in terms of number of publications are: country—China, institution—Sila Science (Turkey), journal—Fuel. Regarding the author keywords, the transitions from the first to third generation biodiesel * as well as reaction optimization were indicated [8]. * The article content indicates that the authors probably used the word biodiesel instead of biofuel incorrectly. |
Rosokhata et al. (2021); 24 | 1974–2020, the whole world | Database: WoS, Scopus Software: VOSviewer | Subject. Renewable energy. Findings. There is a lack of studies dedicated to less developed economies. The most popular research areas are: energy fuels, engineering, science technology, environmental sciences, ecology, and business economics. The majority of papers are published by scientists from US, China, and India. None of the G7 countries, except for US, is actively involved in the scientific development of renewable energy * [9]. * The final conclusion is not consistent with the results presented in the article. |
Chanchetti (2020); 23 | 2000–2015, China, EU, US, Japan | Database: WoS Software: VantagePoint | Subject. Hydrogen storage materials. Findings. The main publishing countries are: China, EU countries, US, and Japan. There is a division between countries where the number of publications remained stable or slightly decreased after 2010 (European Union countries, USA and Japan), and countries where it grew (China and South Korea) [10]. |
Bortoluzzi et al. (2021); 14 | 1998–2019, the whole world | Database: WoS Software: VoSviewer, RStudio, NVivo QSR, SPSS | Subject. Renewable energy technology, sustainable development, multicriteria models. Findings. Renewable energy issues that are widely studied include: hydraulics, photovoltaics, biomass, wind, thermosolar, geothermal, hydrogen, waves, tides and waste. In recent years, there has been a significant growth in the use of Multicriteria Decision-Making/-Aiding methods for the development of renewable energy policies [11]. |
Ziabina et al. (2020); 12 | 1999–2019, UE | Database: Scopus. Sotware: MS Excel, VOSviewer | Subject. Renewable energy sources and energy conservation in the field of economics and social sciences. Findings. Six clusters that combine 131 terms were identified and labelled as follows: energy, energy conservation, sustainable development, renewable energy resources, and costs. The number of publications are expected to increase as a new cycle in developing a neutral carbon economy is about to begin [12]. |
Reyes-Belmonte (2021); 12 | 1990–2020, the whole world | Database: WOS Software: VOSviewer | Subject. Solar energy. Findings: China, US, and India are the most productive countries in terms of solar energy research publications. The list of ten most productive countries accounted for 83% of total publications between 2019 and 2020. Main scientific thematic areas are divided into the following clusters: the first—devoted to chemical processes and materials science involving solar energy, the second—devoted to green energy generation technologies and simulation, and the third—devoted to heat and energy storage [13]. |
Search Option 1 | Search Option Value 2 |
---|---|
String search for publication title, author keywords, indexed keywords, and abstract | “renewable energy” OR “green energy” OR “clean energy” OR “clear energy” OR “sustainable energy” OR “inexhaustible energy source” OR “solar energy” OR “photovoltaic” OR “solar power” OR “solar thermal” OR “wind energy” OR “shore wind” OR “water energy” OR “hydropower” OR “geothermal energy” OR “tide energy” OR “wave energy” OR “ocean energy” OR “biomass energy” OR “biogas” OR “biofuel” OR “bioenergy” OR “bioliquid” OR “aerothermal energy” OR (“municipal” AND “waste” AND “energy” AND “source” |
String search for publication title, keywords, and abstract | “European Union” OR “Europe” OR “EU” |
Document type | Article OR Review OR Conference paper |
Language | “English” OR “German” OR “Polish” OR “French” OR “Czech” OR “Spanish” OR “Italian” OR “Finnish” OR “Croatian” OR “Lithuanian” OR “Portuguese” OR “Hungarian” OR “Slovak” OR “Slovenian” OR “Romanian” OR “Bulgarian” OR “Maltese” OR “Turkish” OR “Modern Greek” OR “Swedish” OR “Dutch” OR “Luxembourgish” OR “Estonian” OR “Danish” OR “Latvian” |
Timespan | 2005–2021 |
Keyword | Occurrences | Synonym |
---|---|---|
electric energies | 26 | electrical energy |
electric energy | 3 | electrical energy |
electric power | 20 | electrical energy |
electrical energies | 4 | electrical energy |
electrical energy | 38 | electrical energy |
electrical power | 34 | electrical energy |
Statistic Description | Totals |
---|---|
Number of records acquired from the Scopus bibliographic resources | 14,428 |
Number of Poland documents; these are publications with the Poland related term in the Scopus database fields: Title, Abstract, Author Keywords, and Indexed Keywords | 630 |
Number of other EU countries documents; these are publications without the Poland related term in the Scopus database fields: Title, Abstract, Author Keywords, and Indexed Keywords | 13,798 |
Number of distinct values in the Keyword field | 52,639 |
Number of distinct values in the Synonym field | 48,124 |
Number of distinct values in the Synonym field with the number of frequency greater than1 (number of synonyms matched to more than one keyword phrase | 2425 |
Number of distinct values in the Synonym field for which the total Occurrence is greater than 10 | 2293 |
Number of distinct values in the Synonym field for which the total Occurrence is greater than 50 | 469 |
Poland | Other EU Countries | ||||
---|---|---|---|---|---|
Number of Articles in Journals | Number of Journals | Number of Articles | Number of Articles in Journals | Number of Journals | Number of Articles |
1 | 169 | 169 | 1 | 1784 | 1784 |
2–9 | 59 | 198 | 2–17 | 1233 | 5299 |
10–17 | 7 | 93 | 18–177 | 101 | 3781 |
18–26 | 6 | 120 | 178–337 | 6 | 1469 |
27–50 | 1 | 50 | 338–497 | 2 | 809 |
498–656 | 1 | 656 | |||
Total | 242 | 630 | Total | 3127 | 13,798 |
Poland | Other EU Countries | ||||
---|---|---|---|---|---|
Journals | Number of Publications | Percentage of Total Publications | Journals | Number of Publications | Percentage of Total Publications |
Energies | 50 | 7.9% | Energy Policy | 656 | 4.8% |
E3S Web of Conferences | 23 | 3.7% | Renewable and Sustainable Energy Reviews | 443 | 3.2% |
Sustainability (Switzerland) | 21 | 3.3% | Renewable Energy | 366 | 2.7% |
Energy | 21 | 3.3% | Energies | 318 | 2.3% |
Renewable and Sustainable Energy Reviews | 19 | 3.0% | Energy | 278 | 2.0% |
Journals | Issues Per Year | H Index | Article Publishing Charges (EUR) | Business Model | Publisher |
---|---|---|---|---|---|
Energy Policy | 12 | 234 | 2840 | Hybrid | Elsevier |
Renewable and Sustainable Energy Reviews | 21 | 337 | 2100 | Open access | Elsevier |
Renewable energy | 15 | 210 | 3060 | Hybrid | Elsevier |
Energies | 24 | 111 | 2100 | Open access | MDPI |
Energy | 11 | 212 | 3250 | Hybrid | Elsevier |
Sustainability (Switzerland) | 24 | 109 | 1910 | Open access | MDPI |
E3S Web of Conferences | na | 28 | na | na | Web of Conferences (EDP Sciences) |
Poland | |||||||
ClusterPL-1 (16) | ClusterPL-2 (14) | ClusterPL-3 (14) | ClusterPL-4 (14) | ClusterPL-5 (12) | ClusterPL-6 (11) | ClusterPL-7 (7) | |
Rank | Red | Green | Blue | Yellow | Pink | Turquoise | Light Brown |
1 | wind power 46-55-191 | biogas 40-57-167 | climate change 40-65-197 | renewable energy 89-79-388 | biomass 71-68-307 | sustainable development 53-67-233 | renewable energy resources 195-85-769 |
2 | electricity generation 35-58-175 | agriculture 26-59-133 | greenhouse gases 34-64-191 | energy efficiency 53-64-197 | bioenergy 31-50-139 | energy utilizatio 47-70-253 | energy policy 91-80-460 |
3 | economics 27-55-158 | commerce 23-54-124 | carbon dioxide 31-63-168 | solar energy 42-55-151 | biofuels 30-52-110 | energy resources 39-58-152 | natural resources 39-66-215 |
4 | electricity 20-42-75 | rural areas 20-51-103 | fossil fuels 23-57-119 | alternative energy 36-57-149 | forestry 20-37-97 | investments 36-63-189 | energy 26-57-123 |
5 | energy consumption 18-32-57 | methane 17-25-53 | gas emissions 20-54-119 | costs 25-57-111 | crops 19-34-86 | geothermal energy 31-43-73 | power generation 22-55-125 |
Other EU countries | |||||||
Rank | ClusterEU-1 (126) | ClusterEU-2 (112) | ClusterEU-3 (94) | ClusterEU-4 (60) | ClusterEU-5 (19) | ||
Red | Green | Blue | Yellow | Pink | |||
1 | biofuels 1183-335-6468 | renewable energy resources 2835-410-16,660 | renewable energy 2125-409-11,642 | solar energy 1026-370-5175 | hydroelectric power 250-255-1313 | ||
2 | biomass 1150-383-7422 | wind power 1234-370-6456 | energy policy 1354-400-9195 | energy efficiency 973-388-6462 | laws and legislation 229-302-1504 | ||
3 | greenhouse gases 989-401-8445 | electricity generation 819-393-5403 | climate change 1001-404-6697 | energy utilization 773-384-5606 | hydropower 156-214-812 | ||
4 | fossil fuels 726-397-5860 | investments 756-394-5397 | sustainable development 911-395-6136 | photovoltaic cells 541-294-2854 | hydroelectric power plants 155-196-698 | ||
5 | bioenergy 695-320-4445 | commerce 743-380-5090 | carbon dioxide 805-391-6318 | photovoltaics 438-290-2331 | risk assessment 149-269-883 |
Keywords Terms | Poland | Other EU Countries | ||
---|---|---|---|---|
First Publication | Articles | First Publication | Articles | |
alternative fuels | 2008 | 11 | 2005 | 193 |
Biodiesel 1 | 2006 | 10 | 2005 | 560 |
Biofuel 2 | 2006 | 64 | 2005 | 2145 |
Biomass 3 | 2005 | 140 | 2005 | 2182 |
carbon capture 4 | 2007 | 6 | 2005 | 149 |
carbon emission | 2005 | 77 | 2005 | 428 |
clean hydrogen | - | 0 | 2011 | 3 |
emission control | 2009 | 17 | 2005 | 457 |
emission reduction | 2005 | 16 | 2005 | 342 |
energy storage 5 | 2008 | 19 | 2005 | 514 |
fuel cells | 2014 | 4 | 2005 | 200 |
green hydrogen | 2020 | 4 | 2006 | 22 |
hydrogen | 2007 | 8 | 2005 | 274 |
hydrogen fuel | 2019 | 3 | 2005 | 59 |
hydrogen networks | - | 0 | 2021 | 1 |
hydrogen production | 2017 | 4 | 2005 | 106 |
hydrogen storage | 2017 | 5 | 2005 | 65 |
smart grids | 2014 | 7 | 2007 | 247 |
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Brzozowska-Rup, K.; Nowakowska, M. Bibliometric Studies on Renewable Energy—Poland Compared to Other EU Countries. Energies 2022, 15, 4577. https://doi.org/10.3390/en15134577
Brzozowska-Rup K, Nowakowska M. Bibliometric Studies on Renewable Energy—Poland Compared to Other EU Countries. Energies. 2022; 15(13):4577. https://doi.org/10.3390/en15134577
Chicago/Turabian StyleBrzozowska-Rup, Katarzyna, and Marzena Nowakowska. 2022. "Bibliometric Studies on Renewable Energy—Poland Compared to Other EU Countries" Energies 15, no. 13: 4577. https://doi.org/10.3390/en15134577