Assessment of the Compliance of Environmental Disclosures by Energy Companies Using GRI Standards with European Sustainability Reporting Standards: A Case Study

Abstract

The Global Reporting Initiative (GRI) has maintained the world’s most comprehensive and dominant sustainability reporting standards. While primarily voluntary, they were widely used by energy companies, especially in the environmental disclosure area. With the recent introduction of the mandatory European Sustainability Reporting Standards (ESRS), companies may face challenges transitioning from GRI to ESRS. In this context, this study provides a comprehensive analysis of the GRI Standards and the ESRS, focusing on their environmental disclosure requirements (‘E’). The purpose of our study is to evaluate the current level of environmental reporting by Polish energy companies based on GRI Standards, assess their compliance with the ESRS requirements under the ‘E’ pillar, and determine the role of GRI disclosures in facilitating the transition to the new standards. A case study approach was employed, using data manually collected from 2023 reports prepared according to GRI Standards by Polish energy companies. Content analysis and the GRI-ESRS Interoperability Index were applied. The findings reveal notable differences in the application of GRI Standards among the companies. The level of environmental disclosures based on GRI Standards is relatively low compared to ESRS requirements, suggesting that companies will face challenges in setting up systems to meet future reporting requirements. This study provides insights into current and emerging practices in environmental reporting, offering valuable implications for EU energy companies preparing their environmental reports in accordance with ESRS requirements.

1. Introduction

The growing threat of a global environmental crisis has heightened public awareness of corporate environmental disclosures, making it a critical area for both academic research and business practice. According to Gerged [1], corporate environmental disclosures refer to the process through which companies communicate the environmental impacts of their operations in external reports, typically through annual corporate reports.

Różańska et al. [2] argue that reporting standards are vital tools that help businesses effectively convey their environmental efforts. These standards enable companies to build stronger relationships with stakeholders, assess their impacts, uncover new business opportunities, mitigate risks, enhance accountability, and improve transparency. Furthermore, they play a pivotal role in the global reporting landscape by promoting the standardization of environmental reporting on issues such as pollution, climate, and biodiversity across various industries and regions. Ultimately, these standards empower investors and other stakeholders to make well-informed decisions.

In the evolving field of environmental reporting, the Global Reporting Initiative (GRI) Standards are widely recognized as a comprehensive framework that encompasses a set of environmental disclosures, providing guidance to organizations worldwide. While primarily voluntary, the GRI Standards have played a significant role within the EU in assisting companies to comply with the mandatory disclosure requirements of the Non-Financial Reporting Directive (NFRD) [3]. However, with the recent adoption of the European Sustainability Reporting Standards (ESRS) under the Corporate Sustainability Reporting Directive (CSRD) [4], companies operating in the EU now face the challenge of transitioning from the GRI Standards to the mandatory ESRS.

Rimmel et al. [5] emphasize that the shift from voluntary to mandatory sustainability reporting standards poses a significant challenge for companies required to comply. At the same time, this transition creates opportunities for research, such as assessing companies’ readiness for the change and analyzing the interoperability of various standards. Similarly, Bais et al. [6], exploring the state of research on GRI, call for further studies on the implications of the introduction of ESRS for current GRI users.

Previous studies [7,8,9,10,11] have revealed numerous gaps in the compliance of energy sector companies’ reports with GRI Standards. This has raised questions about the role of GRI Standards in facilitating the transition to ESRS, particularly concerning environmental disclosure topics (‘E’). According to GRI and EFRAG [12], companies already utilizing GRI reporting can leverage their existing practices when preparing ESRS-compliant sustainability statements. While many organizations are preparing for the implementation of ESRS, academic discourse on how GRI Standards can support ESRS compliance remains in its early stages [13].

Responding to this call and contributing to the emerging academic discussion, this study evaluates the current environmental reporting models of energy companies based on the GRI Standards, assesses their compliance with ESRS requirements under the environmental (‘E’) pillar, and examines the role of GRI disclosures in ensuring readiness for the transition to the new standards.

Additionally, it offers a comparative analysis of the GRI Standards, which are widely utilized in sustainability reporting within the energy sector, and the recently introduced ESRS, with a focus on ‘E’ disclosure requirements. The adoption of the case study method is justified by the nascent stage of research in this area.

To achieve this aim and enrich the debate on the GRI-ESRS interoperability, this study addresses the following research questions (RQ):

• RQ1: To what extent do energy companies adopt the GRI Standards for environmental (“E”) topics in their sustainability reports?
• RQ2: To what extent do the GRI-based sustainability reports of energy companies align with the environmental (“E”) requirements of the ESRS?
• RQ3: To what extent have the GRI-based environmental (“E”) disclosures of energy companies contributed to their compliance with the ESRS?

The energy sector was chosen for this research due to its pivotal role in addressing climate change and its status as the largest contributor to greenhouse gas emissions in the EU, according to Eurostat [14]. As an environmentally sensitive industry, energy companies face significant pressures to adopt sustainable practices that mitigate environmental degradation, align with global initiatives like the Sustainable Development Goals (SDGs), and comply with evolving regulatory frameworks.

The legal framework and the reporting standards enable energy firms to gain insight into the value chain, anticipate stakeholder expectations, manage climate-related risks, and improve their resilience in the mid- and long run. Their role in the energy transition, as highlighted by the International Renewable Energy Agency (IRENA) [15], underscores their importance in advancing renewable energy and sustainability objectives, with a broader influence on achieving other SDGs [16]. This makes the sector a key focus for assessing compliance with GRI Standards and ESRS in environmental reporting.

Poland’s energy sector plays a crucial role in the country’s economy and is undergoing a significant transformation due to both domestic and international climate policies. Historically reliant on coal, Poland has one of the highest shares of coal-based electricity generation in the European Union. However, in response to EU climate goals and the European Green Deal, the country is gradually shifting toward renewable energy sources and improving its sustainability reporting practices.

Given these dynamics, studying the Polish energy sector provides valuable insights into how companies in carbon-intensive industries adapt to evolving regulatory frameworks, including the GRI Standards and ESRS. Poland’s experience also reflects broader challenges faced by other economies with fossil fuel dependencies, making the findings relevant for an international audience interested in the global energy transition and corporate sustainability reporting. To date, recent studies in the energy sector, both in Poland [17,18,19] and globally [20], have not addressed the transition from GRI Standards to ESRS, which represents a significant research gap, particularly in the context of evolving sustainability regulations.

The research methodology is based on comparative document analysis, using content analysis of environmental disclosures. The study is divided into three stages: selecting large Polish energy companies reporting under the NFRD and preparing 2023 reports based on GRI Standards; linking GRI disclosures to ESRS disclosures using the GRI-ESRS Interoperability Index; and identifying gaps in sustainability information in the 2023 reports. A binary scoring system was used to assess disclosure, with cross-checking to minimize subjectivity.

Our findings suggest that the greater the compliance with GRI environmental disclosures, the easier it will be for energy companies to transition to ESRS environmental requirements.

This study makes several important contributions to the environmental reporting literature, particularly to the well-established GRI research stream. First, it introduces a unique research tool, the GRI-ESRS Interoperability Index, to assess the preparedness of GRI users for implementing ESRS. Second, it identifies the role of GRI Standards in ensuring readiness for the transition to the new standards. Third, it highlights the similarities and differences in environmental reporting under the GRI and ESRS frameworks. Additionally, this study provides insights into current and emerging practices in environmental reporting, offering valuable implications for EU energy companies preparing their environmental reports in accordance with ESRS requirements.

The paper is organized as follows. The second section provides essential background information, covering the GRI and the applicability of its standards among organizations, as well as the mandatory ESRS introduced by the CSRD. It also includes a comparative analysis of environmental disclosures under the GRI Standards and the ESRS. The subsequent sections present theoretical perspectives for examining environmental disclosure and relevant literature related to the energy sector. This is followed by an explanation of the research methodology and a presentation of the results. Finally, the last section discusses the study’s findings and contributions, addresses its limitations, and proposes a future research agenda.

2. Background Information

2.1. Global Reporting Initiative (GRI) and the Applicability of Its Standards

The GRI is an independent, international non-profit organization established in Boston, MA, USA, in 1997. Currently headquartered in Amsterdam, the Netherlands, it operates a global network of seven regional offices in Brazil, China, India, the USA, South Africa, Colombia, and Singapore [21]. Initially, the GRI focused on developing guidelines and standards to enhance sustainability reporting and assist businesses and governments in understanding and communicating their impacts on critical sustainability issues, such as climate change, human rights, governance, and social well-being [22].

Over time, the GRI’s mission has expanded beyond creating standards and guidelines to include broader goals. These include harmonizing the sustainability reporting landscape, positioning itself as the central hub for sustainability reporting frameworks, promoting efficient and effective sustainability reporting, and driving the use of sustainability information to improve organizational performance [22]. Its ultimate aim is to contribute to creating a sustainable future [21].

Since its inception, the GRI has released six iterations of its guidelines and standards, adapting them over time to ensure accessibility and consensus-building through dialog, feedback, roundtables, and pilot testing. The first version of the GRI Guidelines (G1) was published in 2000. Subsequent versions (G2, G3, G3.1, and G4, released between 2002 and 2013) evolved significantly in terms of structure and content. This iterative process culminated in 2016 with the launch of the first global standards for sustainability reporting—the GRI Standards.

The GRI Standards, developed through a transparent, multi-stakeholder process, are issued by the Global Sustainability Standards Board, an independent standard-setting body established by the GRI. These standards are freely available, enabling organizations to download and utilize them at no cost for sustainability reporting. They are structured into modular, interrelated components, including Universal Standards, Sector Standards, and Topic Standards, which provide a comprehensive view of an organization’s material topics, associated impacts, and management approaches.

The standards are continuously updated and expanded. Recent developments include new Topic Standards on Tax (2019) and Waste (2020), a significant update to the Universal Standards (2021), and the ongoing rollout of Sector Standards.

Adams et al. [23] note that although the GRI Standards can be applied by a variety of organizations, their adoption varies across countries, industries, and companies. Global research by KPMG [24] reveals that GRI remains the dominant sustainability reporting framework, used by over two-thirds of the N100 and three-quarters of the G250 companies. However, regional variations exist, with uptake rates of 75% in the Americas, 68% in Europe and Asia-Pacific, and 62% in the Middle East and Africa. Singapore, Taiwan, and Chile are among the countries leading in GRI adoption.

The GRI report database [25] for the period 2016–2020 shows that organizations in Europe published the most reports (40%, or 1805 reports), with Spain, Sweden, Germany, Switzerland, and Italy being particularly active. This trend is partly explained by the EU’s NFRD, which required certain entities to disclose non-financial information from 2017 onwards.

Prior studies have shown significant regional differences in GRI adoption. Legendre and Coderre [26] linked these variations to national business cultures, finding fewer reports in shareholder-focused cultures compared to stakeholder-oriented ones. Economic development also influences adoption. Tauringana [27] documented limited interest in sustainability reporting in developing regions like Africa, parts of Asia, and Latin America. Moreover, as Halkos and Nomikos [28] argue, government policy plays a role, with countries where governments place less emphasis on sustainability reporting showing lower adoption rates.

At the sectoral level, Caricasole [29] identified financial services, energy, food and beverage, and utilities as the most active users of the GRI Standards from 2000 to 2018. Conversely, sectors like construction, real estate, chemicals, and mining lagged. This disparity can be attributed to varying stakeholder pressures [30,31] and sector-specific social and environmental risks [32].

Company-specific factors, such as size, also influence GRI adoption. Larger enterprises are more likely to disclose sustainability information due to external pressures and agency concerns [33,34]. The NFRD further reinforces this trend, as its requirements apply only to entities with over 500 employees. Caricasole [29] confirmed that large companies lead in GRI reporting but noted growing engagement from small and medium-sized enterprises during 2000–2018. She also emphasized the importance of experience, with returning reporters consistently outnumbering first-time adopters of the GRI Standards.

This background provides valuable context for analyzing the transition from GRI-based reporting to ESRS, as mandated by the CSRD. It also underscores the relevance of examining this issue among large energy sector companies in Poland, which, as highlighted by Bartoszewicz and Szczepankiewicz [35], have a long history of using the GRI Standards\Guidelines.

2.2. European Union Regulations and Standards for Sustainability Reporting

The CSRD [4] marks a pivotal legislative advancement, significantly expanding and tightening the scope of the NFRD [3]. It extends reporting requirements beyond listed companies to include large non-listed entities and certain small and medium-sized enterprises. These organizations must report in compliance with the ESRS, developed by the European Financial Reporting Advisory Group (EFRAG), an independent body supporting the EU in financial and sustainability reporting. The ESRS aim to establish a unified framework for environmental, social, and governance (ESG) reporting, including ESRS 1 and ESRS 2, which outline general requirements and disclosures, and ten additional standards addressing specific ESG topics [36]. Entities already covered by the NFRD must transition to the new standards starting in 2024, with the first reports due in 2025.

Developed in collaboration with the GRI, the ESRS ensures alignment with existing sustainability frameworks, particularly in materiality assessment. While the GRI initially focused on one-directional materiality—evaluating a company’s impact on society and the environment—it now incorporates the double materiality concept, which also considers how sustainability risks affect the company. The ESRS fully embraces this double materiality approach, aligning on indicators but differing in methodology and reporting depth.

Organizations already using the GRI framework are well-positioned for ESRS adoption but must adapt to stricter requirements. The ESRS introduce enhanced features, such as a structured materiality approach, expanded data collection under double materiality, and alignment with intergovernmental guidelines on due diligence. These standards also require more granular disclosures, particularly in environmental domains, posing new challenges for organizations.

2.3. Comparative Analysis of Environmental Disclosures Under the GRI Standards and the ESRS

The ESRS include five environmental (E) topic standards, E1–E5, covering 32 sub-topic disclosures: 9 related to climate (E1), 6 to pollution (E2), 5 to water and marine resources (E3), and 6 each to biodiversity and ecosystems (E4) and resource use and circular economy (E5) (

Table 1. Environmental disclosures in accordance with the ESRS.

ESRS E Standards	The Number and Title of the Specific Environmental Disclosure
ESRS E1: Climate Change	E1-1 Transition plan for climate change mitigation E1-2 Policies related to climate change mitigation and adaptation E1-3 Actions and resources in relation to climate change policies E1-4 Targets related to climate change mitigation and adaptation E1-5 Energy consumption and mix E1-6 Gross Scopes 1, 2, 3, and Total GHG emissions E1-7 GHG removals and GHG mitigation projects financed through carbon credits E1-8 Internal carbon pricing E1-9 Anticipated financial effects from material physical and transition risks and potential climate-related opportunities
ESRS E2: Pollution	E2-1 Policies related to pollution E2-2 Actions and resources related to pollution E2-3 Targets related to pollution E2-4 Pollution of air, water, and soil E2-5 Substances of concern and substances of very high concern E2-6 Potential financial effects from pollution-related impacts, risks, and opportunities
ESRS E3: Water and marine resources	E3-1 Policies related to water and marine resources E3-2 Action and resources related to water and marine resources E3-3 Targets related to water and marine resources E3-4 Water consumption E3-5 Potential financial effects from water and marine resources-related impacts, risks, and opportunities
ESRS E4: Biodiversity and ecosystems	E4-1 Transition plan on biodiversity and ecosystems E4-2 Policies related to biodiversity and ecosystems E4-3 Actions and resources related to biodiversity and ecosystems E4-4 Targets related to biodiversity and ecosystems E4-5 Impact metrics related to biodiversity and ecosystems E4-6 Potential financial effects from biodiversity and ecosystem-related impacts, risks, and opportunities
ESRS E5: Resource use and circular economy	E5-1 Policies related to resource use and circular economy E5-2 Action and resources related to resource use and circular economy E5-3 Targets related to resource use and circular economy E5-4 Resource inflows E5-5 Resource outflows E5-6 Potential financial effects from resource use and circular economy-related impacts, risks, and opportunities

Source: Own elaboration based on [36].

). Beyond these environmental standards, the ESRS also incorporate additional indicators addressing governance processes, controls, and procedures (GOV), interactions between strategy and business models with material impacts, risks, and opportunities (SBM), impact, risk, and opportunity management (IRO), and metrics and targets (MT).

According to the ESRS Implementation Guidance document, “EFRAG IG 3 List of ESRS Datapoints” [37], there are 354 mandatory (“shall”) data points (without Minimum Disclosure Requirements) for the ‘E’ standards specified in the application and disclosure requirements. Of these, 146 are narrative, 46 are semi-narrative, and 162 are numerical. Additionally, the document identifies 137 voluntary (“may”) data points in this domain. This detailed list of requirements is available in Excel format [38] and can serve as a foundation for conducting a data gap analysis or a data collection exercise.

In the case of GRI, there are eight environmental (E) topic standards, ranging from GRI 301 [22] to GRI 308 [22], which include a total of 32 sub-topic disclosures. Specifically, these disclosures are distributed as follows: three for materials (301) [22], five for energy (302) [22], five for water and effluents (303) [22], four for biodiversity (304) [22], seven for emissions (305) [22], five for effluents and waste (306) [22], and two for supplier environmental assessment (308) [22], respectively (

Table 2. Environmental disclosures in accordance with the GRI Standards.

GRI Standards	The Number and Title of the Specific Environmental Disclosure
GRI 301: Materials 2016	301-1 Materials used by weight or volume 301-2 Recycled input materials used 301-3 Reclaimed products and their packaging materials
GRI 302: Energy 2016	302-1 Energy consumption within the organization 302-2 Energy consumption outside of the organization 302-3 Energy intensity 302-4 Reduction in energy consumption 302-5 Reductions in energy requirements of products and services
GRI 303: Water and Effluents 2018	303-1 Interactions with water as a shared resource 303-2 Management of water discharge-related impacts 303-3 Water withdrawal 303-4 Water discharge 303-5 Water consumption
GRI 304: Biodiversity 2016	304-1 Operational sites owned, leased, managed in, or adjacent to, protected areas and areas of high biodiversity value outside protected areas 304-2 Significant impacts of activities, products, and services on biodiversity 304-3 Habitats protected or restored 304-4 IUCN Red List species and national conservation list species with habitats in areas affected by operations
GRI 305: Emissions 2016	305-1 Direct (Scope 1) GHG emissions 305-2 Energy indirect (Scope 2) GHG emissions 305-3 Other indirect (Scope 3) GHG emissions 305-4 GHG emissions intensity 305-5 Reduction in GHG emissions 305-6 Emissions of ozone-depleting substances (ODS) 305-7 Nitrogen oxides (NOX), sulfur oxides (SOX), and other significant air emissions
GRI 306: Waste 2020	306-1 Waste generation and significant waste-related impacts 306-2 Management of significant waste-related impacts 306-3 Waste generated 306-4 Waste diverted from disposal 306-5 Waste directed to disposal
GRI 307: Environmental Compliance 2016	307-1 Non-compliance with environmental laws and regulations
GRI 308: Supplier Environmental Assessment 2016	308-1 New suppliers that were screened using environmental criteria 308-2 Negative environmental impacts in the supply chain and actions taken

Source: Own elaboration based on [22].

). In addition, for each material topic, the organization is required to report on the management of material topics in accordance with the GRI 3-3 requirements under GRI 3: Material Topics [22]. Furthermore, the reporting organization must disclose information on financial implications, as well as other risks and opportunities related to climate change, in accordance with GRI 201-2 under GRI 201: Economic Performance [22].

Based on a comparative analysis of the GRI and ESRS environmental disclosure at the sub-topic level, we identified the main similarities and differences between the two sets of standards.

The ESRS places special emphasis on climate change through a dedicated topic standard, E1, consisting of sub-indices E1-1 to E1-9. Unlike GRI Standards, which primarily focus on voluntary disclosures, ESRS E1 emphasizes compliance with recent European environmental legislation. Nonetheless, it incorporates elements from GRI Standards 302 (Energy), 305 (Emissions), 201 (Economic Performance), and GRI disclosure 2-19 (Remuneration policies) [22]. For instance:

• Sub-topic E1-5 (Energy consumption and mix) aligns with GRI 302-1 disclosure, measuring energy consumption by source in MWh and GRI 302-3 (Energy intensity). Differences exist between the E1-5 and GRI 302-1 in how energy consumption data are aggregated and disaggregated;
• Sub-topic E1-6 (Gross Scopes 1, 2, 3, and Total GHG emissions) corresponds to GRI 305-1, 305-2, and 305-3, measuring emissions across all scopes in metric tons of CO₂ equivalent. It also aligns with GRI 305-4 (GHG emissions intensity), though ESRS requires reporting the intensity ratio for total GHG emissions, while GRI separates Scope 3 from Scopes 1 and 2;
• Sub-topic E1-9 (Anticipated financial effects from material physical and transition risks and potential climate-related opportunities) relates to GRI 201-2 (Financial implications and other risks and opportunities due to climate change).

The remaining sub-topics of the E1 standard, including E1-7 and E1-8, do not have equivalents in GRI disclosures.

The ESRS E2 (Pollution), covering sub-topics E2-1 to E2-6, draws from GRI Standards 303 (Water and Effluents), 305 (Emissions), and 306 (Waste). For example:

• Sub-topic E2-4 (Pollution of air, water, and soil) relates to GRI disclosure 305-7 (Nitrogen oxides (NOX), sulfur oxides (SOX), and other significant air emissions), 306-5 (Water bodies affected by water discharges), and also to GRI 2-17 (Compliance with laws and regulation);
• Targets related to pollution, included in E2-3, correspond to GRI 303-2 (Management of water discharge-related impacts). However, GRI focuses on minimum water quality standards, while ESRS emphasizes ecological thresholds.

Both standards include water-related disclosures, with ESRS E3 corresponding to GRI 303. Common elements include:

• Total water consumption: ESRS E3-4 and GRI 303-5, both measured in m³;
• Management practices: ESRS E3-1 (Policies related to water and marine resources) aligns with GRI 3-3 (Management of material topics);
• Action and resources related to water: ESRS E3-2 relate to GRI 303-1 (Interactions with water as a shared resource).

Biodiversity is addressed by ESRS E4 (sub-topics E4-1 to E4-6) and GRI 304 (disclosure 304-1 to 304-4). While both address similar themes, the ESRS adopts a qualitative approach, whereas GRI emphasizes quantitative metrics.

ESRS E5 includes five sub-topics covering renewable and non-renewable resources, materials, and waste, paralleling GRI Standards 301 (Materials) and 306 (Waste). For instance:

• ESRS E5-4 (Resource inflows) corresponds to GRI 301-1 (Materials used by weight or volume), 301-2 (Recycled input materials used), and 306-1 (Waste generation and significant waste-related impacts);
• ESRS E5-5 (Resource outflows) relates to the remaining disclosures from GRI 306 (Waste), namely 306-2 (Management of significant waste-related impacts), 306-3 (Waste generated), 306-4 (Waste diverted from disposal), and 306-5 (Waste directed to disposal). However, GRI emphasizes quantitative data, while ESRS requires narrative disclosures.

Finally, some ESRS sub-topics, such as E2-6, E3-5, E4-6, and E5-6, address unique areas like the potential financial impacts of risks and opportunities related to pollution, water and marine resources, biodiversity and ecosystems, resource use, and the circular economy. These topics have no direct equivalents in GRI disclosures.

This analysis underscores the distinctive focus of ESRS on compliance and financial implications compared to the voluntary and metric-oriented approach of GRI Standards.

3. Previous Literature

3.1. Theoretical Perspectives for Exploring Environmental Disclosure

Environmental deterioration, driven by industrialization in the late 20th and early 21st centuries, has become a critical global challenge, drawing attention from governments, businesses, researchers, and the international community, as noted by Cho and Patten [39]. Milestones like the Paris Climate Change Conference in 2015 and COP26 in 2021 have advanced global climate discussions, emphasizing the impact of climate change on humanity, as highlighted by Savaresi [40].

The increasing interest of influential stakeholders in environmental information has driven academic researchers to explore this field both theoretically and empirically. The theoretical perspectives, research streams, and number of publications on corporate environmental disclosure (CED) have evolved over time.

Hahn et al. [41] identified three primary theoretical perspectives to explain corporate engagement in environmental disclosure: economic theories of disclosure, sociopolitical theories, and institutional theories. According to Clarkson et al. [42], economic theories suggest that companies choose to disclose environmental information voluntarily based on a cost–benefit analysis. In contrast, Hahn and Lülfs [43] argue that socio-political theories view CED as a response to social or political pressures from various stakeholders. Lastly, based on institutional theory, Hahn et al. [40] contend that CED is motivated by the need to fulfill government and institutional requirements while still prioritizing profit maximization.

Bilal et al. [44], through a bibliometric review of 560 articles on CED published in 215 journals between 1982 and 2020, came to the conclusion that all of these theories have been widely used by researchers to analyze the levels, determinants, and outcomes of CED practices. According to the authors, stakeholder theory is frequently applied in the core CED literature, which focuses on supporting societal welfare and meeting stakeholders’ expectations. Legitimacy theory, commonly used by firms to enhance their corporate image, is evolving within CED research. Its earlier application has emerged as a key theme, while its later use is on the decline. This suggests that legitimacy theory may become less significant in future CED research or lose its relevance entirely. Since 2016, institutional theory’s role in explaining corporate engagement with environmental and social disclosures has gained significant momentum. During this period, CED research has gained greater prominence, partly due to the Paris Climate Change Accord, which brought increased objectivity to environmental disclosures. As a global agreement, the Paris Accord also emphasized the importance of the GRI guidelines in shaping CED practices. In response, both companies and countries are actively pursuing strategic environmental and climate change targets. Meanwhile, academics, using methodologies such as content analysis and disclosure indices, are examining how the GRI framework enables organizations to address and communicate the impacts of issues like climate change, human rights, and corruption on businesses and economies.

3.2. Environmental Reporting Under the GRI Guidelines/Standards in the Energy Sector

The topic of sustainability reporting based on GRI Standards/Guidelines has been extensively explored in the previous literature, as highlighted by recent reviews, for example, by Bais et al. [6], E-Vahdati and Aripin [45], Mougenot and Doussoulin [46], and Kulevicz et al. [47]. Although the GRI Standards are well designed, featuring detailed reporting guidelines and regular updates to adapt to changes, and despite their popularity and global recognition, they are not fully implemented in practice, particularly among energy companies.

Bashtovaya [48] highlighted notable variations in corporate approaches to sustainability reporting within the energy sector, influenced by the institutional context of the companies. For instance, while American reports address globally significant environmental performance topics, these issues are often excluded from reports by Russian companies. Similarly, Jindřichovská and Purcărea [49] compared different country-specific approaches to environmental reporting in the energy sector within the Czech Republic and Romania. In the institutional context of China, Dong and Xu [50] presented a case demonstrating that mining firms quickly adopted sustainability disclosure practices in response to regulatory pressures from the state government and stock exchanges.

Yehezkiel et al. [7] examined the level of sustainability report disclosure for 269 selected companies in the basic materials and energy industries across developed countries (the UK, Germany, and France) and developing countries (Indonesia, Malaysia, and Thailand) during the period 2019–2022. The authors concluded that sustainability disclosure levels aligned with GRI Standards are higher in developed countries than in developing countries across the analyzed sectors. Additionally, they identified differences in the completeness of sustainability topic presentations: environmental topics are more comprehensively disclosed in developed countries, while developing countries tend to focus more on providing detailed disclosures related to social topics.

Fadillah and Norhamida [51] further contributed to the discussion by analyzing the level of disclosure of GRI Standards in sustainability reports of energy and financial sector companies listed on the Indonesia Stock Exchange. Using a case study method, their research applied a content analysis approach to 53 selected companies for the 2022 period. Their findings revealed that the energy sector exhibited a higher level of GRI compliance compared to the financial sector. Additionally, they observed that the industry in which a company operates influences the topics most frequently disclosed in sustainability reports. These findings align with prior research suggesting that sectoral differences impact sustainability reporting practices, as companies in environmentally sensitive industries tend to provide more comprehensive environmental disclosures.

Mamun [8] examined Australian electricity retailers’ reporting practices based on the GRI G4 sector-specific guidelines for the period 2018–2019. The study found significant variations in companies’ disclosures both between and within the three categories of sustainability reporting: economic, environmental, and social. Furthermore, the majority of retailers failed to address more than two-thirds of the GRI indicators.

Talbot and Boiral [9] assessed the compliance of climate information in GRI reports from energy-sector companies and identified significant inconsistencies between the data disclosed and the claimed transparency associated with GRI’s A or A+ application levels. Nonconformities were found in 98 out of the 105 reports analyzed (93.3%). These nonconformities were categorized into three main groups: uncertainties regarding measurement methods and emission calculations, incomplete or unrepresentative information on performance indicators, and omissions of information. This finding is particularly surprising, given that all the reports reviewed were assigned the highest application level of the GRI guidelines and were, in most cases, audited by external auditors.

Szczepankiewicz and Mućko [10] analyzed the sustainability reports of Polish energy and mining companies prepared in accordance with GRI G4 for the year 2014. Their findings indicate that companies perform internal analyses of their environmental impacts and have developed and implemented environmental management systems compliant with GRI guidelines. However, a more detailed analysis revealed significant diversity in the approaches to the content of these reports. The authors stressed that their conclusions are preliminary and highlighted the need for further research on the standardization of environmental reporting.

Zrnic et al. [11] analyzed data from the sustainability reports of EU energy companies for the period 2016–2019 and found that companies do not effectively apply GRI Standards when preparing their reports. Moreover, environmental indicators have shown a slight decline since 2017. The authors concluded that companies arbitrarily select which GRI indicators to include in their reports. In cases where certain indicators are omitted, no reasons are provided. While some companies briefly note that a specific indicator is not applicable, they fail to offer an explanation for its exclusion. Szczepankiewicz [10,18,19,35] and others conducted research in the following years [47,48,49,50,51]. The absence of published GRI indicators in corporate reports highlights a voluntary approach to their implementation. The voluntary nature of the GRI Standards reflects the lack of mandatory adoption at the EU level. While sustainability reporting was mandatory under NFRD, no specific reporting methodology was prescribed.

Numerous gaps in the compliance of energy sector companies’ reports with GRI Standards, as identified in the previous literature, have raised questions about the role of GRI Standards in the transition to ESRS, particularly regarding environmental disclosure topics (‘E’). According to GRI and EFRAG [12], companies already using GRI reporting can build upon their existing efforts when preparing ESRS-compliant sustainability statements. While many organizations are evaluating their readiness for the ESRS transition, the academic discussion on how GRI Standards can support ESRS compliance remains in its early stages [13].

Therefore, the aim of our study is to evaluate the current level of environmental reporting by Polish energy companies based on GRI Standards, assess its compliance with the ESRS requirements under the ‘E’ pillar, and determine the role of GRI disclosures in facilitating the transition to the new standards.

4. Research Methodology and Data

4.1. Case Selection

To address the three research questions, we employed a case study methodology, which enables an in-depth analysis of phenomena within the context of a specific organization and situation.

First, we looked for large Polish companies from the energy sector that are required to report environmental information under NFRD and are currently preparing their 2023 reports based on the GRI Standards. From the selected companies, we eliminated those that applied the ESRS for the first time in 2023, as well as those that were not Polish companies. Ultimately, this study focuses on the consolidated sustainability reports of three companies—Enea Group, Energa Group, and PGE Group—listed on the Warsaw Stock Exchange (

Table 3. Research sample characteristics.

Company Name	Number of Employees	Assets (in Thousand PLN)	Revenues (in Thousand PLN)	Profit/Loss (in Thousand PLN)
ENEA Group	18,227	39,110,745	48,183,419	−442,623
PGE Group	42,552	113,443,000	95,964,000	−4,902,000
ENERGA Group	8732	31,679,000	22,081,000	606,000

Source: Own elaboration based on data from financial statements.

).

The selected companies hold substantial influence as key players in the energy sector, driven by their economic impact and the obligation to transparently disclose information, particularly on environmental issues. Moreover, analyzing these firms, acknowledged as leaders in ESG reporting within Poland, offers a valuable opportunity to explore how organizations that have already implemented global standards are now adapting to new, more stringent EU regulations. Finally, these three companies serve as an important benchmark for other businesses that also need to adjust their reporting practices to align with evolving EU standards. The insights generated from this study aim to provide meaningful guidance to other companies facing similar transitions.

Furthermore, the selection of ENEA, PGE, and ENERGA as case companies is strongly substantiated by their status as the three largest Polish energy groups, all listed on the Warsaw Stock Exchange and recognized for their established practices in non-financial reporting. Importantly, these companies have a long history of applying GRI Standards in their sustainability reports, which positions them as relevant examples to analyze the alignment between GRI-based disclosures and ESRS requirements. Specifically, PGE and ENEA have been applying GRI Standards since at least 2016, while ENERGA began systematic GRI-based reporting in 2017. Their long-standing use of GRI guidelines enables a robust assessment of the extent to which existing reporting practices based on GRI facilitate or hinder compliance with the new ESRS framework. Additionally, as large and publicly visible companies with significant environmental footprints, ENEA, PGE, and ENERGA face heightened scrutiny from various stakeholders, which makes their environmental reporting practices particularly relevant for academic analysis.

4.2. Data Collection and Disclosure Index

The data were manually collected from the non-financial information statements for 2023, which were prepared in a consolidated form and made available on the companies’ websites. These statements were formally based on the NFRD, which has been transposed into national law through the Accounting Act. The 2023 statement was prepared in compliance with the GRI Standards.

A binary scoring system was employed. Each data point in each company was scored separately according to the extent of information disclosed in each report. If the data point was present in the report, it scores 1, and 0 otherwise. To minimize the subjectivity of this evaluation, we utilized a cross-checking approach, whereby the scores assigned by one author were independently reviewed by another author, and vice versa. Any discrepancies among the authors were subsequently discussed and resolved through consensus.

For each company and for each environmental disclosure requirement (from E1-1 to E5-6), the environmental disclosure requirement coverage index was computed according to the following formula:

$$\mathrm{Environmental}\mathrm{disclosure}\mathrm{requirement}\mathrm{coverage}\left(\mathrm{EDRC}\right)\mathrm{index}={\displaystyle \frac{\begin{array}{l}\mathrm{The}\mathrm{sum}\mathrm{of}\mathrm{scores}\mathrm{obtained}\mathrm{by}\mathrm{the}\mathrm{company}\mathrm{within}\\ \mathrm{a}\mathrm{particular}\mathrm{environmental}\mathrm{disclosure}\mathrm{requirement}\end{array}}{\begin{array}{l}\mathrm{Number}\mathrm{of}\mathrm{data}\mathrm{points}\mathrm{within}\mathrm{a}\mathrm{particular}\\ \mathrm{environmental}\mathrm{disclosure}\mathrm{requirement}\end{array}}}$$

To determine the coverage sub-index for each environmental standard (E1–E5), we calculated the average of the EDRC indices using the following formula.

$$\mathrm{Environmental}\mathrm{standard}\mathrm{coverage}\left(\mathrm{ESC}\right)\mathrm{sub-index}={\displaystyle \frac{\begin{array}{l}\mathrm{Sum}\mathrm{of}\mathrm{EDRC}\mathrm{indices}\mathrm{within}\mathrm{a}\mathrm{particular}\\ \mathrm{environmental}\mathrm{standard}\left(\mathrm{E}\right)\end{array}}{\begin{array}{l}\mathrm{Number}\mathrm{of}\mathrm{EDRC}\mathrm{indices}\mathrm{within}\mathrm{a}\mathrm{particular}\\ \mathrm{environmental}\mathrm{standard}\left(\mathrm{E}\right)\end{array}}}$$

To determine the total environmental coverage index, we calculated the average of the environmental standard coverage sub-indices according to the following formula:

$$\mathrm{Total}\mathrm{environmental}\mathrm{coverage}\mathrm{index}={\displaystyle \frac{\mathrm{Sum}\mathrm{of}\mathrm{ESC}\mathrm{sub-indices}}{5\left(\mathrm{number}\mathrm{of}\mathrm{ESC}\mathrm{sub-indices}\right)}}$$

4.3. Steps of Analysis

The research methodology is based on a comparative document analysis. The primary research tool is the content analysis of environmental disclosures. This analysis was divided into three stages, corresponding to the three research questions.

In the first stage, we examined which GRI Standards related to the environmental area were reported by each company in their report for 2023.

In the second stage, we used the GRI-ESRS Interoperability Index to link GRI disclosures to the corresponding ESRS disclosures within each company’s report for 2023. This stage involved analyzing how GRI Standards will influence the preparation of future reports compliant with ESRS.

The GRI-ESRS Interoperability Index [12] functions as a guide that shows which GRI disclosures have equivalents in the ESRS framework. It helps determine the alignment between ESRS and GRI Standards, showing which components of GRI-compliant reports can be directly carried over to ESRS. Furthermore, it identifies gaps in disclosures, specifically areas that ESRS requires detailed reporting for but were either not covered or considered optional in the GRI Standards.

Since the conclusions drawn from the second stage were quite general, we moved to the third stage, where we examined the presence or absence of all specific data points (from E1-1 to E5-6) in each company’s non-financial report prepared under the GRI Standards for 2023. At this stage, we were able to identify gaps in sustainability information that need to be addressed by energy companies in our research sample.

5. Results

The results of the first stage are presented in

Table 4. Environmental disclosure under GRI Standards and their coverage in 2023 reports.

GRI Environmental Disclosure	GRI Disclosure by Enea	GRI Disclosure by PGE	GRI Disclosure by Energa
301-1	X	X	X
301-2		X	X
301-3
302-1	X	X	X
302-2
302-3	X
302-4
302-5
303-1	X	X
303-2
303-3	X	X	X
303-4	X	X	X
303-5		X	X
304-1	X	X	X
304-2		X	X
304-3	X	X	X
304-4		X
305-1	X	X	X
305-2		X	X
305-3	X	X
305-4	X
305-5		X	X
305-6
305-7		X
306-3	X		X
306-4		X	X
306-5		X	X
307-1
308-1
308-2
2-19
2-27	X
201-2	X		X
3-3	X	X	X
Number of standards covered (percentage)	15 out of 34 (44%)	20 out of 34 (59%)	17 out of 34 (50%)

Source: Own elaboration based on case study.

. Regarding RQ 1, the extent of adoption of the GRI Standards for environmental (‘E’) topics in the sustainability reports is relatively low. The coverage of GRI Standards on which the environmental report was based is 44% for Enea Group, 59% for PGE Group, and 50% for Energa Group. In some cases, companies used similar standards (e.g., 301-1 or 302-1) or did not base their reports on the same standards (for example: 301-3, 302-4, 302-5, 307-1, or 308-2). The comparison shows significant variation in the GRI Standards used by the companies, as well as a selective approach to their adoption. It is expected that energy companies will consider the environmental area significant and, thus, include all relevant disclosure standards. Moreover, given the more detailed requirements arising from the new ESRS, companies may encounter difficulties in reporting environmental issues comprehensively.

The results of the second and third stages are presented in

Table 5. GRI Standards coverage of environmental ESRS and environmental disclosure coverage indices.

Name	Data Type	Reported GRI Standards by Enea	Reported GRI Standards by PGE	Reported GRI Standards by Energa	EDRC Indices for Enea	EDRC Indices for PGE	EDRC Indices for Energa	Standard Deviation of Coverage Indices
ESRS E1-1	narrative; monetary; semi-narrative; gYear				0.56	0.56	0.44	0.07
ESRS E1-2	MDR-P; semi-narrative	3-3	3-3	3-3	0.50	0.50	0.50	0.00
ESRS E1-3	MDR-A; semi-narrative; ghg emissions; narrative	201-2; 3-3	305-5	201-2; 305-5; 3-3	0.64	0.45	0.36	0.14
ESRS E1-4	narrative; table; table/ghg emissions; table/percent; table/decimal; MDR-T; semi-narrative	3-3	3-3; 305-5; 305-1	3-3; 305-5	0.30	0.77	0.31	0.27
ESRS E1-5	percent; energy; semi-narrative; narrative; monetary	302-1; 302-3	302-1	302-1	0.57	0.48	0.30	0.13
ESRS E1-6	monetary; table; table/percent; table/ghg emissions; narrative; percent; ghg emissions; intensity; semi-narrative	201-1; 305-1; 305-3; 305-4	305-1; 305-2; 305-5; 305-3	305-1; 305-5; 305-2	0.41	0.29	0.12	0.15
ESRS E1-7	narrative; semi-narrative; table; table/ghg emissions; ghg emissions; percent; date				0.00	0.00	0.00	0.00
ESRS E1-8	table; table/narrative; table/monetary; Table/percent				0.00	0.00	0.00	0.00
ESRS E1-9	monetary; percent; narrative; Table/narrative; integer; Table/percent; narrative/monetary	201-2	201-2	201-2	0.49	0.40	0.24	0.12
ESC sub-index for E1					0.38	0.38	0.25	0.08
ESRS E2-1	MDR-P; narrative				0.80	0.60	0.20	0.31
ESRS E2-2	semi-narrative; narrative; MDR-A	3-3	3-3	3-3	0.40	0.60	0.60	0.12
ESRS E2-3	narrative; semi-narrative; MDR-T	3-3	3-3		0.33	0.58	0.00	0.29
ESRS E2-4	table; table/mass; mass; narrative; percent	2-27	305-7		0.16	0.16	0.00	0.09
ESRS E2-5	table; table/mass				0.00	0.00	0.00	0.00
ESRS E2-6	monetary; percent; narrative				0.27	0.36	0.00	0.19
ESC sub-index for E2					0.33	0.38	0.13	0.13
ESRS E3-1	MDR-P; narrative; semi-narrative				0.69	0.77	0.00	0.42
ESRS E3-2	narrative; MDR-A; semi-narrative	303-1; 3-3	303-1; 3-3		0.60	0.60	0.00	0.35
ESRS E3-3	narrative; semi-narrative; MDR-T	3-3	303-1		0.18	0.55	0.00	0.28
ESRS E3-4	volume; percent; table/volume; narrative	303-3; 303-4	303-3; 303-4; 303-5	303-3; 303-4; 303-5	0.18	0.45	0.36	0.14
ESRS E3-5	monetary; narrative				0.00	0.50	0.00	0.29
ESC sub-index for E3					0.33	0.57	0.07	0.25
ESRS E4-1	narrative	3-3	3-3; 3-3		0.44	0.83	0.00	0.42
ESRS E4-2	MDR-P; narrative; semi-narrative				0.62	0.76	0.10	0.35
ESRS E4-3	narrative; monetary; semi-narrative; MDR-A	304-3; 3-3	304-3; 3-3	304-3; 3-3	0.79	0.50	0.50	0.16
ESRS E4-4	semi-narrative; narrative; MDR-T				0.33	0.42	0.50	0.08
ESRS E4-5	narrative; Area; Integer	304-1	304-4; 304-1; 304-2	304-1; 304-2	0.18	0.50	0.32	0.16
ESRS E4-6	monetary; narrative; narrative/monetary				0.00	0.50	0.00	0.29
ESC sub-index for E4					0.39	0.59	0.24	0.17
ESRS E5-1	MDR-P; narrative				0.80	1.00	0.80	0.12
ESRS E5-2	narrative; MDR-A	306-2; 3-3	306-2; 3-3	306-2; 3-3	0.67	0.83	0.75	0.08
ESRS E5-3	narrative; semi-narrative; MDR-T	3-3	3-3	3-3	0.64	0.79	0.79	0.08
ESRS E5-4	mass; percent; narrative	301-1; 306-1	301-1; 301-2	301-1; 301-2; 306-1	0.56	0.33	0.56	0.13
ESRS E5-5	narrative; table/percent; Percent; mass	306-2; 306-3	306-4; 306-4; 306-5; 306-2	306-2; 306-3; 306-4; 306-5	0.39	0.30	0.42	0.06
ESRS E5-6	monetary; narrative				0.17	0.83	0.00	0.44
ESC sub-index for E5					0.54	0.68	0.55	0.08
Total environmental coverage index					0.39	0.52	0.25	0.14

Source: Own elaboration based on case study.

. In terms of RQ 2, based on the “Interoperability” document, it can be concluded that the GRI Standards do not fully encompass all the data points required by ESRS. Additionally, notable differences are found in the metrics of specific indicators and the units of measurement, particularly when it comes to monetary units and quantitative measures (e.g., tons, liters, cubic meters).

Consequently, ESRS include considerably more indicators in the analyzed cases compared to GRI. Some of the indicators reported in 2023 under the GRI Standards were compatible with specific ESRS requirements and, thus, aligned with them. An example is GRI Standards 3-3 or 302-1, which are compatible with E1-2 and E1-5, respectively. Moreover, some GRI Standards cover several environmental ESRS. For instance: GRI standard 201-2 covers E1-3 and E1-9; GRI standard 3-3 covers E1-2, E1-4, E2-2, E2-3, E3-2, E4-1, E4-3, E5-3, and GRI standard 306-2 covers E5-2, E5-5.

Nonetheless, significant gaps exist where GRI did not offer complete coverage. Certain ESRS requirements, like ESRS E1-7 or E1-8, were either only partially addressed or lacked sufficient detail due to differences in the scope of GRI Standards compared to ESRS.

To make the analysis more in-depth, we moved to the third step and used the content analysis method to examine the existence or absence of ESRS data points in the reports from 2023, in terms of RQ 3.

The results show that the total environmental coverage index is highest for the PGE Group (0.52), indicating that, on average, 52% of the ESRS data points were covered in the 2023 report. The lowest value for this index was observed for the Energa Group, where only 25% of the ESRS data points were included in the 2023 non-financial report.

The ESC sub-index levels for E1 and E5 are quite similar across all the analyzed companies. However, the ESC sub-index for E2, E3, and E4 shows similarity only between the Enea and PGE Groups, both of which are higher compared to the levels observed for the Energa Group.

Surprisingly, some environmental ESRS were reported by energy companies; despite this, according to the GRI-ESRS Interoperability Index, they should not be covered by GRI Standards. The examples are E1-1, E2-1, E2-5, E3-1, E4-2, and E4-4.

Moreover, data points relating to ESRS E1-7, E1-8, E2-5 were not addressed in the 2023 report of any of the companies.

6. Discussion

6.1. Summary of Findings

The forthcoming shift from GRI Standards to ESRS may partially support the comparability of environmental indicators, particularly in areas where GRI Standards had already established a solid foundation (such as greenhouse gas emissions and water use). However, the increased intricacy of the ESRS, along with its broader focus on double materiality and expanded financial metrics, has presented challenges for companies in the energy sector in achieving full alignment across all indicators. The companies have made notable strides, but further actions are necessary to achieve full comparability and meet the entire range of ESRS requirements.

The findings indicate substantial differences in the GRI Standards applied by the companies within the research sample, along with a selective manner in which these standards are adopted. It is anticipated that energy firms, in particular, will view environmental matters as highly important and, therefore, incorporate all pertinent disclosure requirements. Moreover, the results confirm that the extent of environmental disclosures based on GRI Standards in 2023 is relatively low compared to the ESRS requirements. The result, which reveals a gap in compliance with the GRI Standards, aligns with previous studies [7,8,9,10,11].

This means that companies will face a significant challenge in establishing a system for collecting and processing data, which will enable them to prepare a sustainable report in the coming years. The study showed that, in some areas, the extent of disclosures will not require significant supplementation, as it is already at a relatively high level. However, there remain many areas where the analyzed companies will have substantial work to do.

The GRI Standards have been instrumental in shaping environmental reporting practices for numerous organizations, including companies in the energy sector. Moving forward, GRI Standards will continue to be pivotal in facilitating compliance with the ESRS by providing a solid reporting foundation. The case study based on companies in the energy sector confirmed that GRI Standards played a vital role in helping them meet ESRS requirements, especially by building on pre-existing reporting practices.

These findings are consistent with a prior study [13], which indicated that companies already utilizing GRI Standards are likely to adapt more seamlessly to the new ESRS framework.

One of the key challenges in transitioning from GRI to ESRS lies in their structural differences. The GRI Standards, being voluntary and modular, allow for selective disclosure, while the ESRS are mandatory and require holistic coverage, including governance and strategy-related financial metrics. Furthermore, while GRI emphasizes material topics determined by the reporting entity, the ESRS is grounded in the principle of double materiality, requiring broader stakeholder consideration and economic impact. These conceptual and structural divergences may result in the need for significant adjustments to internal data collection systems, staff workflows, and audit processes. Consequently, companies will need to reevaluate their current sustainability infrastructures to ensure full alignment with ESRS, beyond simple disclosure equivalence.

It is crucial to highlight that shifting from environmental GRI Standards to environmental ESRS involves not only compliance with regulatory requirements but also a reconfiguration of internal reporting systems, data collection methodologies, and strategic sustainability efforts. The inherent difficulties of this transition include limitations in resources, maintaining data quality, and embedding sustainability metrics into the organization’s main business strategies [5]. The case companies need to allocate sufficient time and resources to properly train their staff and gain a comprehensive understanding of these new responsibilities. Additionally, adopting ESRS may necessitate further financial investments in reporting systems and human capital to achieve compliance.

To address the inconsistencies between GRI and ESRS-aligned disclosures, organizations can implement a dual-mapping strategy during the transition period, where each GRI disclosure is cross-referenced with its corresponding ESRS datapoint.

Table 6. ESRSE’s environmental disclosures that can be reported based on a database adapted to GRI reporting standards.

GRI Standards	ESRS E Standards
The Specific Environmental Disclosure	Environmental Disclosures That Can Be Reported Based on a Database Adapted to GRI Reporting Standards	The New Environmental Disclosure
301-1 301-2 301-3	E2-4 Pollution of air, water, and soil E2-5 Substances of concern and substances of very high concern E5-4 Resource inflows E5-5 Resource outflows	E2-1 Policies related to pollution E2-2 Actions and resources related to pollution E2-3 Targets related to pollution E5-1 Policies related to resource use and circular economy E5-2 Action and resources related to resource use and circular economy E5-3 Targets related to resource use and circular economy
302-1 302-2 302-3 302-4 302-5	E1-5 Energy consumption and mix	E1-1 Transition plan for climate change mitigation E1-2 Policies related to climate change mitigation and adaptation E1-3 Actions and resources in relation to climate change policies E1-4 Targets related to climate change mitigation and adaptation E1-6 Gross Scopes E1-1, 2, 3, and Total GHG emissions E1-7 GHG removals and GHG mitigation projects financed through carbon credits E1-8 Internal carbon pricing
303-1 303-2 303-3 303-4 303-5	E3-2 Action and resources related to water and marine resources E3-4 Water consumption	E3-1 Policies related to water and marine resources E3-3 Targets related to water and marine resources
304-1 304-2 304-3 304-4	E4-3 Actions and resources related to biodiversity and ecosystems	E4-1 Transition plan on biodiversity and ecosystems E4-2 Policies related to biodiversity and ecosystems E4-4 Targets related to biodiversity and ecosystems E4-5 Impact metrics related to biodiversity and ecosystems
305-1 305-2 305-3 305-4 305-5 305-6 305-7	E1-5 Energy consumption and mix E1-6 Gross Scopes E1-1, 2, 3, and Total GHG emissions E1-7 GHG removals and GHG mitigation projects financed through carbon credits	E1-1 Transition plan for climate change mitigation E1-2 Policies related to climate change mitigation and adaptation E1-3 Actions and resources in relation to climate change policies E1-4 Targets related to climate change mitigation and adaptation E1-8 Internal carbon pricing
306-1 306-2 306-3 306-4 306-5	E5-2 Action and resources related to resource use and circular economy E5-3 Targets related to resource use and circular economy E5-4 Resource inflows E5-5 Resource outflows	E5-1 Policies related to resource use and circular economy
307-1	E1-9 Anticipated financial effects from material physical and transition risks and potential climate-related opportunities E2-6 Potential financial effects from pollution-related impacts, risks and opportunities E3-5 Potential financial effects from water and marine resources-related impacts, risks and opportunities E4-6 Potential financial effects from biodiversity and ecosystem-related impacts, risks and opportunities E5-6 Potential financial effects from resource use and circular economy-related impacts, risks and opportunities
308-1 308-2	E1-5 Energy consumption and mix E1-6 Gross Scopes E1-1, 2, 3 and Total GHG emission E2-4 Pollution of air, water and soil E2-5 Substances of concern and substances of very high concern E3-2 Action and resources related to water and marine resources E4-3 Actions and resources related to biodiversity and ecosystems E5-2 Action and resources related to resource use and circular economy E5-3 Targets related to resource use and circular economy E5-4 Resource inflows E5-5 Resource outflows

Source: Own elaboration based on [22,36].

presents the evolution of the environmental disclosures in accordance with the GRI Standards and ESRS E Standards.

Moreover, using the EFRAG IG 3 datapoint list as a validation tool can help companies assess the completeness and accuracy of their reports. These practices would not only mitigate inconsistencies but also enhance transparency and ensure stakeholders receive a clear, harmonized view of environmental performance. Future studies could build on this approach by examining the effectiveness of such tools in reducing reporting gaps.

6.2. Future Research and Limitations

The shift from voluntary sustainability standards to mandatory requirements with the introduction of the CSRD will present challenges not only for those preparing reports under the new EU regulations but also for academics. Future research could build on the findings of this study in several ways.

First, a longitudinal analysis of energy companies’ reporting practices could provide insights into how organizations adapt to the ESRS over time and whether the transition from GRI to ESRS improves the quality and consistency of environmental disclosures.

Second, expanding the geographic scope of the research to include companies from other EU member states could reveal regional variations in the adoption and integration of GRI and ESRS. Such comparative studies would help assess the global relevance of ESRS and their impact on sustainability reporting practices.

Third, further investigation could explore the specific challenges companies face in aligning with ESRS requirements, such as data collection, system integration, and stakeholder engagement. This research could include interviews or surveys with sustainability practitioners to provide a practical perspective.

Fourth, the emphasis on double materiality and the value chain, as critical elements of sustainability disclosure under ESRS, opens a significant area of research.

Finally, examining the role of external factors—such as regulatory support, market pressures, and technological advancements—in shaping the adoption of ESRS could offer valuable insights for policymakers and organizations. Future studies could also evaluate the broader implications of ESRS on other pillars of sustainability (social and governance) to provide a holistic understanding of its impact.

Our research has some limitations that must be recognized. Since disclosures under thematic ESRS, in particular the environmental area, are required only when determined to be material through a double materiality assessment, companies may not report the same information as they did in previous years. This limits the ability to directly compare historical and future reporting practices. Moreover, the relevance of this study’s findings may change over time due to the ongoing development of ESRS and the introduction of new frameworks, which could affect the generalizability of the results in subsequent years. Additionally, while our study focuses on the common points between GRI and ESRS to highlight elements that may facilitate the transition, we acknowledge that structural differences between the two frameworks could create challenges for companies adapting to ESRS requirements. Furthermore, as the study is based on three companies, its results may not be fully applicable to other firms, particularly those operating in different sectors or regions. These limitations indicate that while the study provides important insights, its conclusions should be interpreted with these constraints in mind.

7. Conclusions

This study highlights both the challenges and opportunities associated with the transition from GRI Standards to ESRS in the energy sector. While GRI Standards have provided a strong foundation for environmental reporting, achieving full compliance with ESRS will require significant additional efforts. The shift toward double materiality and more detailed financial disclosures introduces complexities that necessitate greater investment in reporting infrastructure, data management, and expertise.

The case study confirms that although some areas of environmental disclosure align closely between the two standards, substantial differences remain, particularly in data collection processes and the integration of financial metrics. As companies navigate this transition, ESRS is expected to enhance reporting comparability and accountability. However, organizations must address key challenges, including resource constraints and the need for comprehensive internal reporting frameworks.

Based on our findings, we recommend that energy companies take several steps to bridge the comparability gaps between GRI and ESRS. First, firms should align their internal reporting frameworks with the ESRS structure by integrating standardized data models that reflect the ESRS indicators (see Table 6). Second, they should invest in capacity-building initiatives, including staff training on ESRS methodologies and double materiality principles. Third, the adoption of ESG data management platforms that offer automated mapping and validation features can facilitate consistent and real-time disclosure. Finally, early engagement with auditors and regulators can help ensure that internal interpretations of ESRS align with regulatory expectations.

Future research should continue to explore the evolving impact of ESRS, with a particular focus on its implementation across different industries and regulatory environments. The findings of this study contribute to the ongoing academic discourse by offering empirical insights into the extent to which energy companies must adapt to these new reporting requirements.