Evaluation of the Relationship Between the Individual Actors of the Quintuple Helix Model and Sustainability

Abstract

The article evaluates the relationships between the individual actors of the Quintuple Helix model and sustainability across EU countries. The model is based on the idea that innovation arises from the collaboration of five key subsystems: government, industry (economy), academia, civil society, and natural capital. Various studies have been conducted to assess the development of the EU’s sustainability goals based on the Triple Helix approach from different perspectives and from the view of the Quintuple Helix. However, we see a gap in the research in that key aspects of the success of these models in the EU have not been examined in terms of their mutual relationships. Therefore, this paper focuses on examining Quintuple Helix systems in the EU, eco-innovation, and sustainability using cluster and correlation analysis. Based on the results, we can infer that Finland, Denmark, Sweden, Austria, and Luxembourg are among the leading EU countries in applying the Quintuple Helix model and promoting sustainability through collaborative innovation processes. The most significant contributions to sustainability within this model come primarily from ecological innovations, intellectual capital, and governance.

1. Introduction

Sustainability is now regarded as one of the key priorities of both the European and global economies. Developed countries and regions have shifted from commodity and manufacturing-based economies toward knowledge and innovation driven economies (Ruhanen & Cooper, 2004). In a dynamic economy, knowledge is a vital organizational resource that offers a sustained competitive advantage, and it is often examined at the contextual level (Leydesdorff, 2012; Hakeem et al., 2023).

The Triple Helix (TH), Quadruple Helix (QH) and Quintuple Helix (5H) models have become valuable tools for studying innovation ecosystems and their interactions within the framework of sustainability development. These models evaluate and explore the possibilities of cooperation in creating sustainable innovations in the relationship between different participants.

The Triple Helix Model is based on the assumption that innovations and innovation processes are the result of cooperation among the state, academic institutions, and industry (Etzkowitz & Leydesdorff, 2000; Hasche et al., 2020). In this model, higher education institutions are considered to be the key drivers of innovation, while businesses, regardless of their size, scope, or type of economic activity, act as both creators and/or consumers of innovations. The model envisions a shift in the public sector’s role, moving from a controlling function to one that stimulates innovation, with a focus on offering broad support, including financial assistance, to economically active entities engaged in innovation (Hasche et al., 2020). The key to the Triple Helix model is collaboration between actors in the search for new innovative solutions, including eco-innovations. Such innovations emerging within this model can contribute to the development of technologies that also focus on environmental protection and social good (E. G. Carayannis & Campbell, 2009). This model represents the basis for modern innovation systems and processes with the aim of influencing sustainability. In this model, it is important that all actors actively support the development of technologies that help mitigate environmental problems while ensuring economic sustainability (Mazzucato, 2018). The transition to a sustainable society requires innovative solutions focused on challenges and new collaborations among a wider array of participants from different sectors, uniting various knowledge and practices, including those from civil society. This is why scientists are increasingly focusing on the Quadruple and Quintuple Helix models, which aim to include the direct contributions of civil society and the natural environment to innovation, alongside the participants of the Triple Helix, as a result of the growing need to find creative solutions to environmental and social problems (Grundel & Dahlström, 2016).

The Quadruple Helix model was put forth to rethink society in the twenty-first century, whereas the Triple Helix concept was created as an intellectual reaction to the burgeoning knowledge-driven economy in the 1990s (Cai & Lattu, 2022). The Quadruple Helix model builds on the Triple Helix model by incorporating civil society. This model integrates social ecology, knowledge, and innovation creation, with civil society playing a crucial role in influencing innovation by interacting across different social subsystems. It focuses on collective collaboration, where knowledge exchange occurs through four subsystems: the educational system (including universities, tertiary education, and human resources), the economic structure (comprising industry, services, financial institutions, and economic assets), the political framework (encompassing legislation, as well as political and legal resources), and the civil domain (involving culture, media, traditions, societal values, television, the internet, and informational resources) (E. Carayannis & Grigoroudis, 2014). Public involvement within the Quadruple Helix model supports inclusive solutions to social problems by involving the public in the creation of innovations that are environmentally responsible. This is particularly important in the implementation of green policies and projects that require the support and involvement of the wider community (E. Carayannis & Grigoroudis, 2016; Jørgensen, 2009; Ranga & Etzkowitz, 2013).

The following stage in the Triple Helix approach, developing the Quadruple Helix, is the Quintuple Helix model. This model is considered one of the most effective because it includes environmental and social elements that are essential to support sustainable development (Crilly et al., 2020). According to E. G. Carayannis and Rakhmatullin (2014), the Quintuple Helix model is made up of five interrelated components: the educational sector, the economic sector, the natural environment, the media and culture-oriented public, and the political sector. This model expands upon the earlier Triple Helix framework by incorporating additional dimensions. Within it, the educational sector includes academic institutions and higher education bodies, the economic sector covers industries, financial institutions, and service providers, while the political sector refers to governmental authorities, along with their policies, regulations, and guiding principles. These five helices function as “subsystems,” allowing knowledge to move from one part of the system to another. The introduction of knowledge into one subsystem initiates a process of generating new knowledge or innovation. The fifth helix serves as a catalyst for generating innovative ideas and newly acquired knowledge aimed at tackling environmental problems. The Quintuple Helix model is a significant actor in the natural environment, which can be understood as a key factor in the innovation processes of the model (E. G. Carayannis & Rakhmatullin, 2014). The natural environment and the economy are intertwined, and this influences the creation of knowledge (Villareal & Calvo, 2015). Within the Quintuple Helix model, innovation processes are focused on developing technologies and innovative solutions that not only improve economic processes, but also protect and restore natural ecosystems and promote sustainability (E. G. Carayannis & Rakhmatullin, 2014). The natural environment has gained significance in innovation research as sustainability concerns increasingly influence decisions in business, government, and education (Ratten, 2016).

In the Quintuple Helix Model, knowledge and its transfer among the different subsystems contribute fundamentally to economic development. Universities are essential contributors in generating, transferring, and promoting sustainable knowledge within both society and the business sector. Cooperation among higher education institutions (such as universities), industry, government bodies, and civil society can lay the groundwork for sustainable national economic development. It can also contribute to strengthening environmental protection, lowering CO₂ emissions, encouraging the responsible management of limited resources, fostering the development of eco-friendly products, and enhancing the quality of life for the country’s population (Kholiavko et al., 2021). Knowledge is converted into innovation, fostering sustainable knowledge that influences environmental performance and quality, grounded in principles of democracy and ecology (E. G. Carayannis et al., 2022a). This model is characterized by a strong emphasis on the development and implementation of green technologies, such as circular economy and sustainable energy sources (C. Li et al., 2022).

The Quintuple Helix is a complex model in terms of its analytical and explanatory scope as well as its design by adding additionally a fifth helix and perspective, which is the natural environment of society, that is the natural environment of society (E. G. Carayannis et al., 2022a, 2022b). The Quintuple Helix Innovation System seeks to connect research and knowledge application that is, innovation with considerations of social ecology. Environmental problems, such as climate issues like global warming, are critical to the survival of human civilization as a whole. At the same time, the Quintuple Helix framework views these ecological challenges as potential drivers for new knowledge and innovation. This future knowledge and innovation may ultimately advance society, the economy, and democracy (E. Carayannis & Grigoroudis, 2014; Taratori et al., 2021). The Quintuple Helix supports the main learning processes for the knowledge economy and fosters a win-win situation among ecology, knowledge (intellectual capital), and innovation, thereby creating synergies between the economy, society, and democracy (E. G. Carayannis et al., 2022a, 2022b; Štofkova et al., 2017). It also promotes sustainable development based on intellectual capital and ecological innovations.

Intellectual capital refers to knowledge, expertise, and intellectual capacity. In the context of sustainability and environmental practices, it is often referred to as green intellectual capital. This includes knowledge of green technologies, sustainable production processes, environmentally responsible management, and the ability to develop and implement innovative solutions that promote environmental sustainability (Shehzad et al., 2023). Green intellectual capital and eco-innovation are closely related in the context of sustainability (Asiaei et al., 2023; Trevlopoulos et al., 2021; Ullah et al., 2022; Marco-Lajara et al., 2023). It can represent potential in the eco-innovation process to more easily identify eco-innovation opportunities, develop sustainable solutions, and implement them in their business operations (W. Li et al., 2023). But eco-innovations can also strengthen green intellectual capital because they generate new knowledge and understanding of effective green solutions (Mulatsih, 2025; Loučanová et al., 2022).

The Quadruple and Quintuple Helix innovation systems have emerged in response to the transformation toward Society 5.0. This concept places human beings at the center of innovation, leveraging the technological advancements of Industry 4.0 and promoting deeper technological integration to enhance quality of life, strengthen social responsibility, and support sustainability (Cai & Lattu, 2022). The Quintuple Helix innovation systems adopt a future-oriented perspective, addressing current societal challenges by implementing problem-solving approaches focused on sustainable solutions. They emphasize sustainable development by integrating innovation, entrepreneurship, and democratic participation (Cai & Lattu, 2022; Wahdiniwaty et al., 2022; E. Carayannis et al., 2024).

Innovation is increasingly driven by the Quadruple and Quintuple Helix models, alongside those outlined in the Triple Helix, which includes society and the environment. These factors play a key role in the creation of sustainable innovation ecosystems (Machado et al., 2024). The study by Shkarupeta and Babkin (2024) also shows that an ecosystem-oriented approach, supported by the Quintuple Helix model, facilitates the rapid exchange of knowledge and resources needed to address eco-innovation challenges, such as high R&D costs and the complex integration of sustainable technologies. The Quintuple Helix thus becomes a crucial framework for coordinating efforts aimed at improving resource efficiency and achieving sustainable outcomes. Helix models are characterized as effective tools for supporting innovation aimed at developing sustainability. The use of these models to support innovation and developing sustainability is also known among EU countries. The leaders in the field of innovation and sustainability in the EU are Sweden, Norway, and Finland (Polt et al., 2014; Zarnic et al., 2010). In countries such as Sweden, the Netherlands, and Germany, policies have been introduced that support the development of green technologies and investments in renewable energy sources, which is reflected in successful innovation processes (Ulpiani et al., 2023; Lahi, 2019). Various studies have been conducted with a focus on assessing the development of EU sustainable goals based on the Triple Helix approach (Lahi, 2019), based on the principles of EU competition law (Bernatt, 2021), the integration of education funding within the Quadruple Helix concept (Kholiavko et al., 2021), etc. However, we see a research gap in the fact that the key aspects for the success of these models in the EU have not been examined. The aim of this research is therefore to examine and evaluate sustainability in the European Union (EU) with regard to the relations among the participants in the Quintuple Helix model.

2. Materials and Methods

The purpose of this study is to analyze and evaluate sustainability in European Union (EU) countries with regard to the interactions among the individual actors within the Quintuple Helix model. Based on the literature review presented above, research elements derived from the Quintuple Helix model were identified using data from the Global Sustainable Competitiveness Index (GSCI) for individual EU countries:

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Natural capital—environmental subsystem;

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Social capital—social subsystem;

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Intellectual capital—educational subsystem;

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Economic Sustainability—economic subsystem;

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Governance—political subsystem.

The study’s research components were carefully selected to represent the five main subsystems of the Quintuple Helix model, ensuring a comprehensive assessment of sustainability across all EU member states. The environmental subsystem is specifically reflected in the Natural Capital indicator, which measures the condition and caliber of natural resources that are essential to sustainable development. The social subsystem is represented by the social capital variable, which includes social networks that foster cooperative innovation and sustainable practices as well as societal cohesiveness and trust. The educational subsystem is represented by intellectual capital, which is crucial for promoting the creation and dissemination of information that supports both technical advancement and education that is focused on sustainability. The economic subsystem is covered by the Economic Sustainability measure, which assesses how well markets and sectors can sustain long-term, sustainable growth. The political subsystem is lastly reflected in the Governance indicator, which highlights the function of institutional efficacy, regulatory frameworks, and policies in directing sustainability projects. The Sustainable Development Goals (SDG) Index was also included, considering the growing significance of global sustainability goals to offer a comprehensive assessment of national sustainability performance in line with globally accepted benchmarks. To capture the technological and ecological innovations driven by systemic interactions among EU countries, the Eco-Innovation Index was incorporated, in line with the Quintuple Helix model’s theoretical premise that innovation emerges from dynamic collaboration among subsystems. This approach enables a thorough and detailed examination, ensuring that the study addresses multiple facets of sustainability and the interconnections among the Quintuple Helix’s components (E. G. Carayannis & Campbell, 2010).

Since sustainability in EU countries is the primary focus of this study, we included the SDG Index among the research elements because it reflects the sustainability performance of individual EU member states.

As Etzkowitz and Leydesdorff (2000) state, innovations result from the cooperation among the individual elements of the Helix model. Therefore, the next research element included in this study was the Eco-Innovation Index from the perspective of EU countries. Secondary data used in the research are from 2024.

Measuring and analyzing the interactions among subsystems is essential, as sustainability and innovation are not the outcomes of isolated factors but rather complex, dynamic, and interconnected processes. An individual assessment of each subsystem (e.g., only environmental capital or only economic sustainability) provides only a partial picture, which may not reveal synergies or potential conflicts between subsystems. The interactions among subsystems such as governance, intellectual capital, social capital, eco-innovation, and environmental capital create a dynamic system in which a change or strengthening of one element can positively or negatively affect the others. For example, strong governance can support integrated education policies and research investments, which in turn stimulate eco-innovation and social engagement. Conversely, weak coordination among subsystems can lead to ineffective policies or fragmented actions that do not support overall sustainability. Therefore, assessing the interactions and relationships between subsystems is critical to identifying the most effective strategies and interventions that can lead to sustainable development at both national and regional levels. By analyzing these relationships, it is possible to design more comprehensive and coordinated policies that take into account interdependencies and synergies across the system. The SDG Index and the Eco-Innovation Index are standardized and globally recognized tools for measuring progress and performance. These indices are constructed based on a transparent methodology that, by combining sub-indicators, comprehensively enables objective comparison of performance. The Global Sustainable Competitiveness Index, as well as the Global Sustainable Competitiveness Index, is considered one of the most comprehensive frameworks for measuring sustainable competitiveness and its sub-indicators. Based on their wide acceptance, transparent methodologies, and standardization, the data are suitable for the purposes of this analysis. Their values are normalized, eliminating the impact of differences in the absolute size of economies and populations.

To evaluate sustainability within the European Union (EU) by examining the relationships among the components of the Quintuple Helix model and their individual actors, cluster analysis was applied. This statistical technique involves computational processes designed to partition a dataset into several relatively homogeneous groups. The core principle of cluster analysis is to form groups where the objects share maximum similarity within each cluster and minimal similarity between different clusters (Halčinová, 2011). Theoretical insights into cluster analysis were applied in practice to assess sustainability across EU countries, focusing on the interactions among the elements of the Quintuple Helix model.

To determine the degree of divergence among the values of the individual elements of the Quintuple Helix model under study, we used the square of the Euclidean distance. The goal of cluster analysis is to achieve a state where objects within a cluster are as similar as possible, while objects from different clusters are as similar as possible. Clustering is also performed on the basis of iteration from the values of the examined indices of individual EU countries in order to maximize the existence of differences between individual cases from different clusters. The characteristics of individual clusters are determined based on secondary data of the examined parameters/indexes and their averages for each identified cluster.

Correlation analysis was used to obtain relevant data for the Quintuple Helix model of EU countries in relation to sustainability and the innovation process of eco-innovations. Correlation analysis is an analysis of the dependence of two variables. It is applied to examine whether changes in one variable result in changes in another one. A direct correlation implies that as one variable increases, the other increases as well. In contrast, an indirect (or negative) correlation suggests that when one variable rises, the other decreases. In the case of Pearson’s correlation (r), the latter parameter applies, i.e., it is a measure of the variance shared between two variables (Moltchanova et al., 2017; Sampaio et al., 2024). The outcome of a correlation analysis is represented by the correlation coefficient r, which ranges from −1 to +1. A value of −1 indicates a perfect negative linear relationship, 0 signifies no linear relationship, and +1 reflects a perfect positive linear relationship. Simply put, the closer the correlation coefficient is to 0, the weaker (or even nonexistent) the relationship between the variables. On the other hand, the closer the value is to +1 or −1, the stronger the linear relationship becomes. However, in real-world scenarios, the coefficient rarely reaches these extreme values, typically falling somewhere within the range. As such, interpreting the results requires a degree of subjective evaluation.

Generally, correlation coefficients from 0.8 to 1 (or −0.8 to −1) indicate a very strong linear relationship. Coefficients between 0.4 and 0.8 (or −0.4 and −0.8) are seen as moderately strong, while those in the range of 0 to 0.4 (or −0.4 to 0) are considered weak. In analyses, the critical ratio (CR) is identified as the value that describes the statistic created by dividing the estimate by its standard error. The critical ratio is compared to a normal distribution with a probability of 95% at a significance level of p = 0.05. In this case, the value 1.96 indicates two-sided significance at the “standard” 5% level (marked *). The critical ratio is compared to a normal distribution with a probability of 99% at a significance level of p = 0.01 (marked **). SPSS Statistics 20 was used to evaluate the analyses (Bentler & Bonett, 1980; Mulaik et al., 1989; SPSS, 2025; Hebák et al., 2013; Sampaio et al., 2024).

3. Results and Discussion

As mentioned above, the goal of this study is to investigate sustainability in EU countries through the lens of the interactions among key participants within the Quintuple Helix model. As a first step, we identified countries that are as similar as possible in relation to the examined parameters (elements) of the Quintuple Helix and at the same time as different as possible from other EU countries. To achieve this, cluster analysis was used. As mentioned above, cluster analysis is an efficient statistical method that allows the identification of natural groups (clusters) within data, whereby objects within a group show a high degree of similarity, while differences between groups are significant. In the context of evaluating the subsystems of the Quintuple Helix model, the use of cluster analysis is particularly beneficial, as it helps to reveal which countries within the European Union have similar characteristics in terms of environmental, social, economic, political, and educational factors that influence sustainability and innovation processes. This method provides the opportunity to sort countries according to complex patterns that would be difficult to capture using only individual assessments of each variable.

The output of this analysis is a dendrogram (see Figure 1), which shows us the grouping of EU countries into two clusters. The first cluster includes the countries Sweden, Finland, Denmark, Austria, and Luxembourg, which use the elements of the Quintuple Helix model more effectively than other countries.

The second cluster includes these countries—Estonia, Germany, Ireland, France, Portugal, Slovenia, Poland, the Netherlands, Belgium, Italy, the Czech Republic, Latvia, Lithuania, Slovakia, Croatia, Spain, Bulgaria, Greece, Hungary, Romania, Cyprus, and Malta. These states achieve lower scores in the individual indexes and lag behind the countries in the first cluster in many areas. They face various challenges in several aspects of sustainable development and innovation. Based on the average values of the individual indexes within each cluster, it can be concluded that the first cluster consists of countries with the strongest performance in this area, while the second cluster includes countries with comparatively lower performance (see

Table 1. Results of analysis of variance of elements Quintuple Helix model of individual EU countries.

Country/ Research Parameters	Natural Capital	Social Capital	Intellectual Capital	Economics Sustainability	Governance	Eco- Innovation	SDG
Sweden	56.4	59.3	71.5	50.6	71.9	161.0	85.7
Finland	56.3	58.0	67.5	52.2	70.6	178.0	86.4
Denmark	46.4	59.6	67.4	52.7	71.5	167.5	85.0
Austria	47.0	55.9	66.2	60.2	66.7	173.9	82.6
Luxembourg	39.8	55.2	64.5	52.3	68.8	179.0	76.8
Average score cluster 1	49.2	57.6	67.4	53.6	69.9	171.9	83.3
Estonia	50.6	55.9	62.9	52.7	69.2	115.5	80.5
Germany	37.8	53.9	73.7	55.5	68.6	141.2	83.5
Ireland	42.5	56.8	58.8	58.9	65.3	110.4	78.7
France	42.7	62.2	66.8	51.3	66.5	130.7	82.8
Portugal	47.7	56.8	60.5	53.0	63.7	105.7	80.2
Slovenia	47.2	60.9	61.8	56.6	59.8	115.9	81.3
Poland	50.5	53.0	60.6	58.5	58.0	67.4	81.7
Netherlands	33.3	62.3	67.0	47.4	68.1	118.8	79.2
Belgium	35.6	59.3	66.4	50.5	66.8	99.8	80.0
Italy	40.6	58.3	62.4	51.2	62.7	129.4	79.3
Czech Republic	43.8	56.2	60.3	56.5	57.8	111.0	81.3
Latvia	54.7	51.4	51.8	55.8	61.7	105.4	81.0
Lithuania	48.9	51.1	54.2	54.1	64.2	103.8	78.1
Slovakia	49.0	54.7	52.9	53.0	57.7	97.4	79.4
Croatia	49.2	50.7	54.3	50.9	61.0	88.8	82.2
Spain	39.1	58.5	53.9	45.5	62.9	116.4	80.7
Bulgaria	49.0	47.6	50.6	51.9	62.4	57.8	75.5
Greece	43.7	49.7	53.9	47.2	61.0	101.6	78.7
Hungary	40.8	46.4	52.6	55.3	56.4	81.2	79.5
Romania	50.1	49.4	41.4	49.7	57.1	84.6	76.7
Cyprus	33.5	56.0	55.1	43.4	56.2	94.7	72.9
Malta	30.0	49.3	58.2	44.8	60.1	79.8	77.0
Average score cluster 2	43.7	54.6	58.2	52.0	62.1	102.6	79.6

).

To determine the relationship among the individual elements of the Quintuple Helix model and sustainability in the innovation process in EU countries, we performed a correlation analysis.

Table 2. Results of correlation analysis of variance of elements of the Quintuple Helix model of individual EU countries.

		Natural Capital	Social Capital	Intellectual Capital	Economic Sustainability	Governance	Eco- Innovation	SDG
Natural Capital	Pearson Correlation	1	−0.103	−0.115	0.459 *	0.141	0.142	0.478 *
	Sig. (2-tailed)		0.609	0.569	0.016	0.482	0.48	0.012
	N	27	27	27	27	27	27	27
Social Capital	Pearson Correlation	−0.103	1	0.676 **	−0.020	0.526 **	0.573 **	0.422 **
	Sig. (2-tailed)	0.609		0	0.92	0.005	0.002	0.028
	N	27	27	27	27	27	27	27
Intellectual Capital	Pearson Correlation	−0.115	0.676 **	1	0.184	0.759 **	0.700 **	0.618 **
	Sig. (2-tailed)	0.569	0		0.357	0	0	0.001
	N	27	27	27	27	27	27	27
Economics Sustainability	Pearson Correlation	0.459 **	−0.020	0.184	1	0.070	0.183	0.389 *
	Sig. (2-tailed)	0.016	0.92	0.357		0.73	0.418	0.045
	N	27	27	27	27	27	27	27
Governance	Pearson Correlation	0.141	0.526 **	0.759 **	0.070	1	0.758 **	0.556 **
	Sig. (2-tailed)	0.482	0.005	0	0.73		0	0.003
	N	27	27	27	27	27	27	27
Eco- innovation	Pearson Correlation	0.142	0.573 **	0.700 **	0.183	0.758 **	1	0.574 **
	Sig. (2-tailed)	0.48	0.002	0	0.418	0		0.002
	N	27	27	27	27	27	27	27
SDG	Pearson Correlation	0.478 *	0.422 *	0.618 **	0.389 *	0.556 **	0.574 **	1
	Sig. (2-tailed)	0.012	0.028	0.001	0.045	0.003	0.002
	N	27	27	27	27	27	27	27

* Correlation is significant at the 0.05 level (2-tailed). ** Correlation is significant at the 0.01 level (2-tailed).

presents an analysis of the elements of the Quintuple Helix model for individual EU countries in relation to sustainability, supported by ecological innovations.

As indicated by the results of the correlation analysis, the following relationships among the individual parameters of the Quintuple Helix model, examined in relation to sustainability supported by ecological innovations, can be identified.

The correlation between economic sustainability and overall sustainability (r = 0.389) can be described as weak. The relationship between natural capital and sustainability (r = 0.478), as well as between social capital and sustainability (r = 0.422), can be considered moderately strong.

These elements of the Quintuple Helix model have a moderately strong linear dependence at the 95% significance level. Similarly, the other parameters examined have a moderately strong linear dependence on sustainability among themselves—Governance versus sustainability (0.556), eco-innovation versus sustainability (0.572), Intellectual capital versus sustainability (0.618). However, their significance is at the 99% significance level. Similar relationships were also manifested among the parameters of the Quintuple Helix model—the relationship of governance versus social capital, ecological innovations, intellectual capital, etc. (as shown in Table 2). This means that if one of these parameters is improved, it can lead to positive changes in the other parameters in the Quintuple Helix model. The correlation coefficient values of statistically significant variables are close to +1, indicating a strong positive relationship. This means that as one variable increases, the other also increases.

Discussion

The Quintuple Helix model has demonstrated its effectiveness as a tool for promoting sustainability-oriented innovation. EU countries that are leaders in innovation and sustainability (such as Denmark, Austria, Sweden, and Finland) use these models to improve environmental and social sustainability. Equivalent results were also found by (Polt et al., 2014). However, our research goes a step further by using a detailed cluster analysis to not only identify the leading countries but also to specify which subsystems—intellectual capital, governance, and eco-innovation—are the primary drivers of sustainability performance (E. Carayannis & Grigoroudis, 2014; E. G. Carayannis et al., 2022a, 2022b). A key aspect in assessing the success of these models is the ability of countries to coordinate policies and promote cooperation among the state, industry, academic institutions, and civil society for the benefit of sustainability (C. Li et al., 2022; Polt et al., 2014). As reported by the European Commission (2020), countries such as Sweden, the Netherlands, and Germany have taken legislative steps to promote sustainable technological development and investments in renewable energy sources, which is reflected in successful innovation processes (Ulpiani et al., 2023). This fact is also confirmed by the Quintuple Helix model we identified. On the other hand, some Central and Eastern European countries face challenges in implementing these models due to a lack of investment and weaker cooperation among key participants (European Commission, 2020). These challenges are not only economic but are also rooted in cultural, regional, and institutional specificities. Cooke et al. (2024) state that we currently operate with models and policies that also apply to the previous one. There is no doubt that countries with strong innovation systems will be more successful than others. The effectiveness of innovation systems is strongly influenced by the cultural and political environment, even within geographically close regions (Schebesch et al., 2024). This suggests that the effectiveness of the Quintuple Helix model must be adapted to the unique cultural and political environment of each country, especially in those with lower performance (Wibisono, 2024).

The study’s conclusions support the Quintuple Helix model’s suitability as a conceptual and analytical framework for comprehending the intricate interactions between innovation and sustainability in EU nations. Consistent with the conclusions of (E. G. Carayannis & Campbell, 2010), the results demonstrate that sustainability is a dynamic result of systemic cooperation among important societal subsystems, especially intellectual capital, governance, and eco-innovation, rather than just the result of environmental or economic efforts. The strong impact of governance and intellectual capital on sustainability outcomes is one particularly noteworthy finding. High sustainability performance nations frequently make investments in infrastructure for research, education, and innovation, which facilitates the creation and sharing of knowledge that promotes eco-innovation. Countries such as Finland and Sweden consistently rank highly in R&D investment as a percentage of GDP (Jarzębowski et al., 2024; Suluk et al., 2024), which directly translates into a high number of patents for green innovations and strong partnerships. This fact is also confirmed by studies by Etzkowitz and Leydesdorff (2000), Khanna et al. (2025), which describe the links between economic growth, environmental sustainability, green innovation, and intellectual capital (knowledge) as an innovation ecosystem of development and cooperation. This fact is evident in our data, which show a significant correlation between the individual sub-systems examined (sustainability versus natural capital—0.478, social capital 0.422, economic sustainability 0.389, governance 0.556 and eco-innovation 0.574). This specific connection confirms that the subsystems under study influence each other and, through synergy, form sustainable development within the Quintuple Helix.

This conclusion is consistent with results of other studies (E. G. Carayannis & Campbell, 2010; Dabić et al., 2021), which highlight the role of intellectual capital as a catalyst for innovation-driven sustainable development, especially when combined with strong policy governance and institutional support.

However, the comparatively weak differentiation power of economic sustainability and natural capital among EU nations raises the possibility that these aspects are increasingly standardized as a result of coordinated EU policy. These results suggest that the main factors influencing sustainability trajectories are not fundamental environmental factors or market functioning, but rather variations in governance and innovation capacities. This emphasizes how crucial it is to have policy structures that improve strategic coordination between institutions and sectors. Policymakers in nations with lower eco-innovation performance should concentrate on enhancing intellectual capital by funding research, higher education, and innovation infrastructure in light of these findings. In order to promote cross-sectoral cooperation among the five helix actors—government, university, industry, civil society, and the environment—governance structures need to be changed concurrently. This strategy may contribute to the development of systemic innovation capabilities that are in line with the demands of the green transition and long-term sustainability objectives.

The above findings underline the necessity of comprehensive, well-coordinated policies at the national and EU levels that link innovation plans with environmental objectives. Enhancing collaboration and communication across all Quintuple Helix members will be crucial as sustainability concerns become more complex. As a result, the model can be used to inform future choices on sustainable development in addition to explaining existing trends.

4. Conclusions

By combining sustainability performance metrics from EU nations and identifying the most influential subsystems in fostering sustainable innovation, this study enhances the empirical relevance of the Quintuple Helix model. The model has proven to be a valuable analytical framework for understanding how the interaction between knowledge, governance, society, the economy, and the environment shapes sustainability trajectories across countries.

The findings from the analysis lead to the conclusion that the Quintuple Helix model supports the development of sustainability. Natural and social capital, as well as economic sustainability, have a significant impact on its development. Intellectual capital is particularly influential, driving ecological innovations that subsequently play a vital role in enhancing the sustainability of EU countries. The impact of these parameters of the Quintuple helix model significantly affects social capital and governance, which subsequently affect sustainability. The mutual relationships among the Quintuple Helix elements in EU countries have a moderately positive impact on sustainability, indicating that the positive development of any one element tends to positively influence the others. Therefore, it is important to implement governance in a way that supports the development of both intellectual capital and ecological innovations, as these have the strongest impact on sustainability and exhibit a strong interconnection with other elements of the model.

In light of these findings, future research should focus on exploring how these interrelationships evolve over time through longitudinal or mixed-method research approaches. It would also be beneficial to examine how regional and cultural specificities influence the strength and configuration of Quintuple Helix interactions, particularly in countries with lower eco-innovation performance. Such insights could support more tailored and effective innovation policies that align with sustainability goals.

Lastly, in order to guarantee that green innovation is given equal weight with economic growth, the incorporation of sustainability goals into economic and innovation strategies should be reinforced. In line with the EU’s larger Green Deal goals, this integrated policy strategy may build a more resilient innovative ecosystem that can handle pressing environmental and social issues.