1 Introduction

Climate change and environmental deterioration pose an existential threat to Europe and the entire world. To deal with these challenges, the European Union – EU, created policy initiatives designed to guide EU countries towards a green transition and transform Europe into a resource-efficient and competitive economy that will ensure economic growth. The latter should be decoupled from resource use, elimination of net emissions of greenhouse gases by 2050, and inclusion of all people and places. This strategy is called the European Green Deal – EGD (EC 2019a).

The EGD offers numerous benefits, such as enhancing the quality of life and promoting the health of both present-day citizens and future generations. This involves ensuring access to clean water, unpolluted air, fertile soil, biodiversity conservation, sustainable energy sources, updated and energy-efficient structures, as well as nutritious and affordable food.

The EGD financial scheme is being deployed since 2019 by one third of the 1.8 trillion-euro investments from the NextGenerationEU Recovery Plan (EC 2021a), and the EU’s seven-year budget. The agreement endorsed a series of measures to align the EU’s climate, energy, transportation, and taxation policies with the goal of achieving a minimum 55% reduction in net greenhouse gas emissions by 2030, in comparison to 1990 levels. The EGD will consistently employ a wide portfolio of policy tools, including regulation and standardization, investment and innovation, national reforms, engagement with social partners, and international collaboration.

To this end, it is imperative to reconsider policies regarding clean energy provision throughout various sectors of economy, including industry, production and consumption, critical infrastructure, transportation, food and agriculture, construction, tax regulations, and social welfare programs (EC 2019b).

The Nexus elements of water, energy, and food play a pivotal role in the framework of the EGD. As the EGD seeks to address the interconnected challenges of climate change and sustainability, it recognizes the inherent linkages among water, energy, and food systems. Water is a critical resource for both agricultural production and energy generation, and its sustainable management is central to the EGD's objectives. Simultaneously, the EGD aims to promote energy efficiency and renewable sources, recognizing the intimate connection between energy practices and environmental impacts. Moreover, the sustainable production and consumption of food are integral components of the EGD, aligning with the Nexus perspective that underscores the interdependence of these crucial elements. By addressing these Nexus elements collectively, the EGD strives for a more integrated and holistic approach to environmental and economic sustainability in the European Union.

Incorporating the EGD into the study of the Nexus approach is logically justified for several reasons. Firstly, the EGD represents a comprehensive and ambitious policy framework addressing the interconnected challenges of climate change, environmental degradation, and sustainable development. The analysis of its components and goals can provide valuable insights into how a Nexus approach is integrated into broader policy initiatives.

Secondly, the EGD emphasizes the need for a holistic perspective on environmental issues, aligning with the core principles of the Nexus approach, which seeks to understand and manage the interdependencies between water, energy, and food systems. Studying the EGD in conjunction with the Nexus approach allows for a more nuanced understanding of how policy frameworks can address complex, intertwined challenges.

Furthermore, the EGD serves as a real-world implementation of sustainable policies, offering practical examples and potential lessons for integrating Nexus thinking into policy development and implementation. By studying the EGD alongside the Nexus approach, researchers can identify synergies and assess the applicability of such integrated strategies in different contexts.

Considering the EGD in the study of the Nexus approach is logical as it provides a tangible example of a large-scale policy initiative that embodies principles aligned with the Nexus perspective, offering insights and practical implications for addressing complex environmental challenges.

The European Commission – EC is the responsible body for planning, preparing and proposing new EU laws and policies. This study makes an overview of the main policies developed by the EC in the sectors of water, energy and food and points out some cases of interconnection among these policies, shedding light on water-related issues in order to contribute to the creation of a society where water is more valued.

This understanding enables the development of integrated policies that promote sustainability, resource efficiency, and climate resilience, aligning with the EGD's goals. By addressing interdependencies, the EU can enhance its transition to a low-carbon, circular economy and achieve a more sustainable and resilient future.

The aim of this paper is to address interdependencies, promote a better comprehension of the water-food-energy Nexus policies and contribute to the identification of the synergies and trade-offs among sectors by the policy makers, that will help the achievement of EGD’s objectives and the transition to a low-carbon, circular economy.

2 Methodology

The methodology employed for the qualitative theoretical study involved an initial analysis of the European Green Deal (EGD), a pivotal document underpinning the European Union's climate transition policies. The focus shifted to the key referential topics of the nexus approach—water, energy, and food. This exploration aimed to identify primary situations and challenges outlined in the EGD related to these thematic areas. The subsequent step involved establishing connections between the identified challenges and prevailing public policies, both existing and in development, aimed at addressing these challenges and safeguarding critical elements.

To complement this analysis, a comprehensive search was conducted on the websites of major institutional bodies in Europe and the EU legislative repository platform, EUR-Lex.europa.eu. This sought to gather information on the policies mentioned and the normative legal documents supporting them. The European policies were then categorized based on the nexus elements they addressed.

Each segment comprises its own challenges and respective initiatives/solutions envisioned in the policies undertaken by the EU.

Subsequently, an examination was undertaken to identify policies that concurrently addressed two nexus elements, with the goal of verifying synergies and correlations between these elements. This dual-element analysis added depth to the understanding of the interconnected nature of water, energy, and food challenges and policies within the context of European climate transition policies and to the UN-SDGs.

3 Findings

3.1 Water policies: the need for a paradigm shift towards water-smart management

Ensuring the availability and sustainable management of water for all is a huge challenge and a sustainable development goal (related to UN SDG 6: Clean Water and Sanitation). Data shows that three out of ten people do not have access to safely managed drinking water services (UN 2018a). Enhancing water efficiency and optimizing water management are vital in balancing the growing and conflicting water needs across different sectors and user groups.

The aquatic ecosystems of Europe are facing mounting challenges. Agricultural and industrial operations, as well as expanding urbanization, are contributing to pollution, excessive water extraction, and alterations in water ecosystems. Today, nearly three-quarters of the European population, including both EU and non-EU countries, reside in urban regions, and this figure is projected to rise to 83.7% by 2050 (UN 2018b), which will implicate on rising water demand. The main drivers will be agricultural and industrial production and domestic water use in cities (Water Europe 2017).

Water scarcity primarily results from a dissonance between water availability and consumption, historically affecting arid and semi-arid regions of Europe (EEA 2021). This situation typically arises due to heightened water demand and diminished availability. However, the advent of climate change is gradually transforming it into a pervasive issue throughout Europe. Climate change is exerting additional stress through more frequent and intense floods and extreme precipitation events, which strain both social and environmental systems (Alves and Schmidt 2022).

Water quality can be adversely impacted by both water scarcity and abundance. For example, overexploitation of aquifers can lead to seawater intrusion and heightened salinity levels. Conversely, intense rainfall can wash agricultural pollutants from farms into rivers and lakes (EC 2021). Diminished water quality results in reduced accessibility of water for both human consumption and the support of ecosystems. In the end, these factors place a strain on the water cycle and have repercussions for the operation and oversight of urban water systems.

Some unexhaustive challenges for the water sector are ensuring good policy fit; overcoming institutional constraints; dealing with aging infrastructure; addressing the lagging innovation rate and, finally, reverting inferior awareness and engagement of users (DWC 2019).

Water security is, therefore, one of the most crucial societal challenges of our society given that water is an enabler of the economy, the social stability, and the sustainable growth (Fig. 1).

Fig. 1
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© Water Europe 2023

The water-smart society model.

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In consequence, all the European policies should put into perspective the real value of water developing systemic solutions and changes towards the healthy water bodies and water provisions. These conclusions are already highlighted by the water community institutions in Europe through the concept of the “Water Smart Society” (a society “in which the true value of water is recognised and realised, and all available water sources are managed in such a way that water scarcity and pollution of water are avoided”, Water Europe 2017).

The EU institutions look to be responsive to this approach as several political communications related to the implementation of the EGD refer to these elements, particularly in the European Parliament and EC actions.

First, the EU has committed to numerous initiatives falling under the theme of "Building a Water-Resilient Economy and Society." These efforts are designed to showcase the viability of a “water-smart” economy and society, where all water resources, including surface, groundwater, wastewater, and process water, are managed in a manner that mitigates water scarcity and pollution, bolsters resilience against climate change, effectively addresses water-related challenges, and ensures the recovery of valuable substances derived from wastewater treatment processes or embedded in used water streams (EU 2018a). International cooperation will be fundamental in building this new model of society within Europe, but also throughout the world.

Secondly, circularity can be very helpful in this pathway as it is an essential part of a wider transformation of industry towards climate neutrality. Circular economy can save substantial natural resources throughout value chains and production processes (Fig. 2).

Fig. 2
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© European Parliament 2023

The circular economy model: less raw material, less waste, fewer emissions.

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In the water segment, there are some actions foreseen in the Circular Economy Action Plan (EC 2020a) such as: (i) the strict monitoring and supporting of the implementation of the requirements of the Drinking Water Directive (EU 2020a) to make drinkable tap water accessible in public places (reducing the dependence on bottled water and preventing packaging waste); (ii) addressing the presence of microplastics in the environment to reduce plastic litter (EU 2018); (iii) encouraging circular approaches to water reuse in agriculture by facilitating water reuse and efficiency, including in industrial processes (EU 2020b); (iv) developing an Integrated Nutrient Management Plan (EC 2022b) to guarantee the more sustainable application of nutrients; (v) the reviewing of the directives on urban wastewater (EU 1991a) and sewage sludge (EU 1991b); (vi) considering new natural means of nutrient removal such as algae.

The key directives concerning water main regulations (some under revision) are the Water Framework Directive (EU 2000), the EU Drinking Water Directive (EU 2020a), the Industrial Emissions Directive (EU 2010a), the Urban Waster Water Treatment Directive (EU 1991a), the Sewage Sludge Directive (EU 1991b), and the Bathing Water Directive (EU 2006).

In addition to these strategies, the EGD itself provides a major framework that establishes important guidelines for the EC future actions. Two strategic axes of the EGD have a direct impact on water as a natural resource essential and vital to the existence of human and non-human people on this planet. The first is Sect. 2.1.7. “Preserving and restoring ecosystems and biodiversity” (EC 2019a) and the second is Sect.  2.1.8 “A zero pollution ambition for a toxic-free environment” (EC 2019a).

The first Section assumes that ecosystems offer vital services, including sustenance, habitats, clean air, and freshwater. In the context of freshwater resources, the EC demonstrates a dedication to fostering more interconnected and effectively managed marine protected areas. Additionally, efforts will be made within the common fisheries policy to reduce the negative effects of fishing on ecosystems, particularly in delicate regions.

The second Section is the reduction of pollution and the establishment of a toxin-free environment. Achieving this goal necessitates proactive measures to prevent pollution generation and effective steps for its remediation. With this objective, the EU is set to enhance its monitoring, reporting, prevention, and remediation efforts related to pollution in water and other natural resources.

To address these interlinked challenges, on the 21st of May 2021, the EC adopted a zero-pollution action plan for air, water, and soil named “Towards a Zero Pollution for Air, Water, and Soil” (EC 2021b). The Commission is actively developing strategies to tackle pollution stemming from urban runoff, as well as addressing pollutants from sources like chemicals (including pharmaceuticals) and microplastics. Furthermore, there is a growing imperative to manage the combined impacts of various pollutants. The Commission will review EU measures to address pollution from large industrial installations. Therefore, all Member States and the EU will need to look more systematically at all policies and regulations.

In parallel, Europe's digitalization will also affect the goals of the EGD, including water related sectors, because it will enable the calibration of consumption of water precisely (as of other precious resources). Therefore, sustainable and cost-effective water management necessitates digital solutions and innovations capable of addressing challenges like climate change, water resource pollution and depletion, and cybersecurity threats. To achieve sustainable and economical water management, it is imperative to implement digital solutions and innovations that can effectively address challenges such as climate change, water resource pollution and depletion, and cybersecurity risks.

At present, EU water policies do not adequately embrace digital solutions, lacking a unified terminology and precise definitions for the integration of digitalization within the water sector (EC 2022a). The absence of policies addressing digital infrastructure, security, integration, standardization, data sharing, and public engagement hinders the optimal utilization of digital solutions.

The adaptation of water management to new technologies is a policy priority. It is essential to improve the definition, standardisation, and implementation of efficient and effective monitoring and early-warning systems. The foundation for smart water systems is based on the emergence of digital information and communication technologies–ICT, the development of the Internet of Things–IoT, the availability of high-performance and low-cost smart monitoring devices, the increased use of Artificial Intelligence–AI and Machine Learning–ML techniques for data analytics and the wide-spread use of powerful computing resources. These tools can contribute significantly to defining policy for the optimal operation of water sectors. Likewise, Geographic Information System–GIS Technology, Remote Sensing–RS Technology, collectively known as 3S technology, and Global Positioning System–GPS Technology, can powerfully improve the monitoring of water systems (WE 2022). With the increasing affordability of Next Generation Internet Technology–NGI, it is essential to enhance our understanding and adoption of various use cases within the water sector (Fig. 3).

Fig. 3
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© Water Europe 2023

Digital water.

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Towards this direction, in November 2022, the EC released the new policy brief “Digitalisation in the water sector recommendations for policy developments at EU level” providing an outline of present gaps in the EU legislative framework that hinder digitalisation in the water sector and offering recommendations on how to overcome them. This policy brief encapsulates the primary policies of the EU within the domain of water.

The following table summarizes the challenges concerned with the water topic and the UE’s actions and policies created to overcome them (Table 1):

Table 1 Water challenges × Water policies
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3.2 Energy policies: the great challenge of creating clean and efficient energy

The domain of energy confronts multifaceted challenges that reverberate across UN-SDGs and significantly impact the EGD. Challenges such as ensuring energy security, reducing carbon emissions, and transitioning to renewable sources are pivotal.

These challenges intersect with SDG 7 (Affordable and Clean Energy) and SDG 13 (Climate Action), emphasizing the need for sustainable and climate-resilient energy practices.

In the context of the EGD, these challenges underscore the imperative to align energy policies with ambitious environmental targets. Achieving a carbon–neutral and circular economy, as outlined in the EGD, necessitates overcoming obstacles related to the integration of renewable energy, energy efficiency, and grid modernization.

Recognizing and addressing these challenges within the energy domain is integral to the successful realization of both SDGs and the overarching objectives of the EGD.

The EGD establishes the goal of “Supplying clean, affordable, and secure energy” (Sect. 2.1.2, EC 2019a) so, a further decarbonising of the energy system is critical. A power sector predominantly reliant on renewable sources should be promoted, striving to ensure a secure and cost-effective energy supply for consumers and businesses. To achieve this, it is crucial to guarantee the complete integration, interconnection, and digitalization of the European energy market.

The 2030 climate and energy framework comprises EU-wide targets and policy goals spanning from 2021 to 2030. These objectives encompass a minimum of 40% reduction in greenhouse gas emissions (compared to 1990 levels), a minimum 32% contribution from renewable energy (EU 2018b), and a minimum 32.5% enhancement in energy efficiency (EC 2023a).

The 40% greenhouse gas objective is put into effect through the EU Emissions Trading System (EU 2003), the Effort Sharing Regulation with Member States' emissions reduction targets (EU 2018c), and the Regulation on Land Use and Forestry (EU 2018d).

All sectors must contribute to the achievement of the 40% mark by both increasing removals and reducing emissions. The climate legislation will be updated to implement the presented at least 55% net greenhouse gas emissions reduction target.

In March 2023, negotiators from the Council and the Parliament reached a preliminary agreement on the renewable energy directive. This agreement aims to increase the proportion of renewable energy in the EU's total energy consumption to 42.5% by 2030, with an additional 2.5% indicative increase that could potentially push it to 45%. Each member state will play a significant role in achieving this collective objective. This interim political accord must receive approval from both institutions.

The negotiators from the Council and Parliament have tentatively agreed upon heightened sector-specific targets in the areas of transport, buildings, industry, and district heating and cooling. These sub-targets aim to accelerate the adoption of renewables in sectors where their integration has been less pronounced (EU 2023a).

The Commission presented an action plan for digitalizing the energy system with measures to help achieve smart integration (EC 2022b). Europe's energy system necessitates a profound overhaul in which digitalization assumes a central role. Given the backdrop of soaring energy costs, accelerating the digitalization of the energy sector is paramount for aiding consumers in reducing their expenditures. Smart buildings, smart meters, electric vehicles, and IoT devices offer vital data that enables scientists and practitioners to monitor energy usage, enhance the integration of renewables, and reduce expenses. Innovative data applications, services, and energy management systems hold untapped potential for energy consumers, but they require additional impetus and appropriate policy backing.

With this objective in mind, the EC is outlining a range of measures to facilitate this endeavor through legislative actions, investments, and collaboration with Member States. In the intermediate timeframe, digitalization will facilitate seamless interactions among various stakeholders. This, notably, empowers consumers to gain more benefits from local energy sources like solar photovoltaics or community-owned wind turbines. For instance, it could enable solar panel owners to sell excess electricity to their neighbors at a more cost-effective rate than purchasing from the grid. Similarly, bidirectional electric vehicle charging enables the utilization of car batteries as an additional electricity resource during peak grid demand hours (EC 2022b).

In the extended run, digitalization will become an essential component for facilitating the incorporation of decentralized renewable energy systems into the grid. Empowered by digital tools and shared data infrastructure, proactive consumers and prosumers who adeptly manage their energy resources can curtail their energy expenses and diminish their environmental impact by accessing energy services precisely when needed.

Simultaneously, the Commission has been advocating for investments in the advancement of smart grid technology and associated digital innovations. Significantly, substantial headway has already been achieved in the digitalization of the energy sector, with 51% of all EU households and small to medium-sized enterprises–SMEs now equipped with smart electricity meters (EC 2019c).

EU digital and energy policies, such as the Renewable Energy Directive (EU 2018b), the Common Rules for the Internal Market and Electricity Directive (EU 2019), the Energy Performance of Buildings Directive (EU 2010b) and the Data Act (EC 2020b), currently provide guidance for the digitalization of energy in areas such as security, privacy, and consumer protection.

To attain the targets outlined in Fit for 55 (EU 2023b) and REPowerEU (EC 2022c) regarding renewable energy and energy efficiency, an estimated EUR 584 billion in electricity infrastructure investments are projected to be required by 2030. Investments in digital solutions, like optimizing the distribution grid, will lead to a reduction in the need for additional capital expenditures to upgrade the current grid infrastructure. This, in turn, will enable the rapid deployment of electric vehicles, decentralized renewable energy sources, heat pumps, and more (Fig. 4).

Fig. 4
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©

Simplified use case for system integration and the optimization of renewable energy roduction and usage: electric vehicles and smart buildings connected to the electricity grid. European Commission 2023a, b

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To enhance the efficiency and intelligence of the grid for the overall benefit of the energy system, the Commission will facilitate closer cooperation between EU Transmission System Operators – TSOs and Distribution Grid Operators–SOs in establishing a virtual model of the European electricity grid.

To facilitate investments, the Commission will strengthen the European Union Agency for the Cooperation of Energy Regulators–ACER and national regulatory authorities in their efforts to establish shared smart grid metrics and associated goals that advance this endeavour.

Conclusively, the preceding outlines the principal directives within the EU’s public policies pertaining to the energy domain.

The following table summarizes the challenges concerned with the energy topic and the UE’s actions and policies created to overcome them (Table 2):

Table 2 Energy challenges × policies
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3.3 Food policies: “from farm to fork”. designing a fair, healthy and environmental-friendly food system.

Data indicates that, following an extended period of decline, global hunger is once again increasing (UN 2018). Some of the key factors causing this reversal in progress are conflict, drought, disasters, climate shocks, the economic consequences of the COVID-19 pandemic, etc.

A report about the 2030 Agenda for Sustainable Development highlights some disturbing facts about SDG 2: Zero Hunger such as the increase of the proportion of undernourished people worldwide; over 150 million children under the age of 5 are experiencing stunting, characterized by low height relative to their age; there are more than 50 million people suffering from wasting (low weight for height); elevated general food prices (which might have had adverse impacts on food security), among others (World Food Programme 2023).

We are living in a global food crisis: 2022 was a year of unprecedented hunger as there were 828 million hungry people worldwide. The count of individuals confronting acute food insecurity has surged, increasing from 135 to 345 million over the past couple of years. In 45 countries, a collective total of 50 million people is confronting famine.

There are other food related challenges: European food production has a reputation for high quality and safety, though the same cannot be said for its sustainability. The transition to more sustainable food production systems has begun, but maintaining current quality standards is a major challenge due to the high scale. Numerous challenges are associated with food production, including issues like air, water, and soil pollution, the role in biodiversity depletion and climate change, the overuse of natural resources, and the significant waste generated within the production process. Conversely, poor-quality diets are linked to health conditions like obesity and cancer (Fanelli et al. 2020). The progress in scientific knowledge and improved access to information have led to increased public awareness and a greater demand for nutritious foods.

For these reasons, the EC presented in May 2020 the Dish-to-Dish Strategy for a Fair, Healthy, and Environmentally Friendly Food System (EC 2020c), which provides a comprehensive approach to tackling the sustainability challenges of food systems, acknowledging the interdependence between the well-being of individuals, the vitality of societies, and the health of the planet. It also holds a central role within the framework of the EGD (Item 2.1.6.) (EC 2019a) and the Commission's agenda to achieve the UN's SDGs (SDG2: Zero Hunger). Shifting towards a sustainable food system can yield advantages for the environment, public health, and society, generate economic benefits, and help the EU recover from the crisis while following a sustainable trajectory.

The growing frequency of droughts, floods, forest fires, and emerging pests serves as a persistent reminder that our food system is in jeopardy and necessitates a shift toward greater sustainability and resilience. Gaining sustainable livelihoods for primary producers, who remain at an income disadvantage, is essential for successful recovery and transition. The strategy seeks to acknowledge and support farmers, fishermen, and other participants in the food chain who have already adopted sustainable practices, facilitate the transition for those yet to do so, and generate further growth opportunities for their enterprises. EU agriculture stands out as the sole major system globally to have reduced greenhouse gas emissions, achieving a 20% reduction since 1990 (EEA 2023). But this path has not been homogeneous in all member states.

The processes of food manufacturing, processing, retailing, packaging, and transportation are notable contributors to pollution in the air, soil, and water, as well as greenhouse gas emissions. These activities also exert a substantial influence on biodiversity. Food systems continue to be a primary driver of climate change and environmental deterioration (about 22% of the world’s greenhouse gas emissions comes from food systems, IPCC 2022a, b). It is imperative to diminish the dependence on pesticides and antimicrobial agents, curtail excessive fertilization, expand organic farming, enhance animal welfare, and reverse the decline in biodiversity.

The “Farm to Fork” (EC 2020c) strategy’s main goals are: (I) to ensure sufficient, affordable and nutritious food within planetary limits; (II) to halve the use of pesticides and fertilisers and sales of antimicrobials; (III) to increase the amount of land devoted to organic farming; (IV) to promote more sustainable food consumption and healthy diets; (V) to reduce food loss and waste; (VI) to combat food fraud in the supply chain; and (VII) to improve animal welfare (Fig. 5).

Fig. 5
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Farm to Fork strategy. © European Commission 2023a, b

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The sustainability of food systems is a worldwide concern, and these systems must adapt to confront diverse challenges. The EU can assume a pivotal role in shaping global standards, formulating new policy initiatives, enforcing existing legislation, and ensuring a just transition (especially in the realms of animal welfare, pesticide management, and environmental protection legislation). This approach considers varying starting positions and disparities in improvement potential across Member States. It acknowledges that the shift towards a sustainable food system will reshape the economic landscape of many EU regions and their interconnected dynamics. Technical and financial assistance from established EU mechanisms, such as the European Agricultural Fund for Rural Development–EAFRD and cohesion funds, will bolster this transformation.

The Commission's commitment to new legislative initiatives will be bolstered by its better regulation tools. Impact assessments will aid in making judicious policy decisions while minimizing costs, aligning with the goals of the EGD.

In an effort to expedite and streamline this transition and to ensure that all food products entering the EU market increasingly embrace sustainability, the Commission will present a legislative proposal outlining a framework for a sustainable food system (FSFS). This framework will foster policy consistency at both the EU and national levels, infuse sustainability into all food-related policies, and enhance the resilience of food systems. Following comprehensive consultation and impact assessments, the Commission will work on establishing shared definitions, overarching principles, and prerequisites for sustainable food systems and products.

The framework will additionally address the obligations of all participants in the food system. Coupled with certification and labelling to assess the sustainability performance of food items and backed by specific incentives, this framework will enable stakeholders to benefit from sustainable practices and gradually elevate sustainability standards to set a benchmark for all food items placed on the EU market. This framework was supposed to be adopted by the Commission by the end of 2023, but is not yet implemented.

In summary, the foregoing delineates the primary food strategies formulated within the public policies by the EC (Table 3).

Table 3 Food challenges × policies
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4 Discussion

Within research and policy domains, there is a growing acknowledgment of the necessity for a more holistic approach to resource planning and management. This approach is crucial in addressing the associated risks to water, energy, and food security since ensuring the security of one resource often involves making trade-offs that affect the security of the others.

Rising demands on natural resources are underscoring the interconnections and trade-offs between food, water, and energy systems, as well as their interactions with land, climate change, and livelihoods. The nexus approach promotes integrated solutions that can enhance efficiency, resilience and sustainability across sectors.

Understanding these dynamics is crucial for effectively tackling sustainability challenges. Similarly, the management of food, water, and energy systems is integral to the attainment of the SDGs (2, 6 and 7) and demands a deeper understanding of the interactions among the objectives, both within and across various levels, to advance human welfare, societal equity, and ecological soundness. In this context, the study of the Nexus approach emerges as an essential tool for policymakers, researchers and stakeholders seeking comprehensive and impactful solutions to navigate the intricate challenges of the twenty-first century.

Towards this direction, in the next paragraphs, the authors analyse and highlight some of the synergies between the public policies and the interaction of the elements mentioned, to provide better comprehension of these connections and underline their relevance. For the needs of this analysis, the authors conducted representative interviews with selected actors involved in the Nexus practice, along with an extensive review and analysis of case studies addressed by European research projects.

4.1 Energy-food nexus

The Energy-Food Nexus refers to the intricate interconnections and interdependencies between energy and food systems. It encompasses the dynamic relationships and feedback loops between the production, distribution, and consumption of energy and food resources. In this Nexus, energy and food are recognized as mutually influencing elements, with changes or challenges in one system directly impacting the other.

In the Farm to Fork Strategy (EC 2020c), the need to increase the sustainability of food production is emphasised. It is precisely in this context that the energy-food nexus stands out, for example, regarding the potential of the circular bio-based economy. Advanced bio-refineries capable of producing bio-fertilizers, protein feed, bioenergy, and bio-chemicals present opportunities for transitioning to a climate-neutral European economy and creating new jobs in primary production.

Farms also have the potential to harness biogas from other waste sources, including those from the food and beverage industry, sewage, wastewater, and municipal waste. Moreover, farm structures like houses and barns often provide ideal locations for the installation of solar panels, and these investments should be a priority.

The Common Agricultural Policy—CAP Strategic Plans (EU 2021) indicates that energy production and use should concern energy which displays the characteristics of sustainability, including as regards greenhouse gases and enhancing carbon sequestration. For example, the CAP refers to the reduction of the environmental impact of the Union wine sector. The Regulation establishes that Member States should increase their “competitiveness in the production and marketing of grapevine products, including energy savings, global energy efficiency and sustainable processes” (art. 57, d, EU 2021).

The use of renewable energy in agriculture/forestry/food industry and the supported investments in renewable energy production capacity, including bio-based, constitute result indicators (R.15, EU 2021) of the CAP to the EU specific objective to contribute to climate change mitigation and adaptation, by reducing greenhouse gas emissions and enhancing carbon sequestration, as well as promoting sustainable energy.

The adoption of energy efficiency solutions in the agriculture and food sectors is important if these investments are made sustainably and without compromising food security or biodiversity. This will be carried out within the framework of clean energy initiatives and programs (EC 2020c).

The CAP Strategic Plans–CSPs serve as the primary mechanism for implementing the CAP from 2023 to 2027. Member States drafted them, and the Commission approved them to ensure the fulfillment of EU-wide objectives. The CSPs support farming and rural areas with more than EUR 300 billion in public investment through the European Agricultural Guarantee Fund–EAGF and the European Agricultural Fund for Rural Development–EAFRD (including national co-financing) (EC 2023d). The CSPs offer significant opportunities to enhance sustainable energy production, primarly through backing agro-photovoltaics and investing in biomethane production.

From the energy policies perspective, the ‘Fit for 55’ package of legislation (EU 2023b) puts all sectors of the EU’s economy (including agriculture, forestry, and food industry sectors) on a path to reach its climate targets in a fair, cost-effective and competitive way. The policies also emphasize the Energy-Food nexus, for example, in the Regulation on Land Use, Forestry and Agriculture – LULUCF (EU 2018d).

4.2 Water-food nexus

The Water-Food Nexus comprehends the intricate relationship between water and food systems, acknowledging the profound interdependence and shared vulnerabilities between these critical resources. In this Nexus, water plays a central role in agricultural production, irrigation, and food processing, highlighting its fundamental importance in sustaining food security. Conversely, the food sector significantly influences water usage patterns, contributing to water stress and competition for resources.

For example, the sustainable use of pesticides, should focus on strengthening provisions related to Integrated Pest Management – IPM and promoting the broader adoption of safe, alternative methods for safeguarding crops from pests and diseases. IPM can facilitate the utilization of alternative control techniques like crop rotation and mechanical weeding, playing a key role in reducing the overall reliance on chemical pesticides and, specifically, the use of more hazardous ones. Crucial to this effort will be agricultural practices that reduce pesticide usage through the CAP (EU 2021). The CSPs should align with this transition and encourage access to advisory services.

The use of chemical pesticides in agriculture contributes to soil, water and air pollution, biodiversity loss and can harm non-target plants, insects, birds, mammals and amphibians. The EC is promoting the availability of pesticides that incorporate biological active ingredients and strengthen the environmental risk assessment procedures for pesticides. Efforts will be made to expedite the pesticide authorization process carried out by Member States.

The Directive 2008/105/EC (EU 2008) issued by the European Parliament and the Council establishes Environmental Quality Standards (EQSs) for specific substances or groups of substances found in surface water. These substances are classified as priority pollutants due to their substantial risk to the aquatic environment, and these standards are aligned with the strategy and objectives of the EU's Water Framework Directive (EU 2000).

Understanding and managing this interconnection are imperative for devising sustainable strategies that address the dual challenges of ensuring water availability for agriculture and maintaining a resilient and secure global food supply.

4.3 Water-energy nexus

The Water-Energy Nexus delineates the complex relationship between water and energy systems, recognizing the symbiotic and interdependent nature of these essential resources. Water is integral to various aspects of energy production, from hydropower generation to cooling processes in thermal power plants. Simultaneously, energy is a critical input in the extraction, treatment, and distribution of water for domestic, industrial, and agricultural use.

Smart digital approaches can support and thoroughly leverage the prospect of the nexus approach. For example, digital solutions have shown to be a powerful tool to reduce energy consumption and thus greenhouse gas emissions during water and wastewater treatment by optimizing treatment processes. Similarly, digital solutions are promising to assure the safe reuse of water for food production (i.e., agricultural irrigation). At the EU level, the Nexus approach and digital solutions for its implementation should be further promoted and embedded by setting some e.g. energy targets in the EU legislation.

However, the new challenges associated with the shift to computationally costly –and energy-intensive –digital solutions must be considered carefully. The cost–benefit analysis must be carefully applied to ensure an energy-positive or energy-neutral EU water sector.

Furthermore, alternative energy produced by the water sector (e.g., through wastewater treatment plants) shall be promoted through EU water as well as energy legislation, such as the Energy Performance of Buildings Directive (EU 2010b). This directive shall be explicitly linked to the EU water legislation.

The water sector can therefore contribute to implementing each country ́s national energy and climate plan (EC 2022a). Also important to address is the water reduction target for energy production or cooling system in the industry. It refers to the amount of water that a company or organization aims to reduce to operate their energy production or cooling system in a more sustainable and efficient manner. It is important to reduce water use in the energy industry, particularly in the production of electricity and heat (Garrido-Barseba et al. 2012).

Another pertinent aspect to address regarding digitalization is the utilization of water in data centers. Water plays a critical role in data centers for cooling, cleaning, and various operational functions, which can carry substantial sustainability implications, especially in areas where water scarcity is a prevalent concern.

Some of the key aspects to consider are (i) water usage, as data centres require great amounts of water for cooling and other processes; (ii) water pollution, as data centres generate wastewater that may contain pollutants, such as heavy metals and chemicals, from the cooling systems and other equipment; (iii) energy use: the energy required to transport, treat and supply water to data centres can contribute to greenhouse gas emissions and climate change; (iv) water efficiency; (v) water recycling; and (vi) water sourcing.

5 Conclusions

The current study sought to offer a comprehensive yet non-exhaustive analysis of the principal policies within the EGD, specifically within the context of the water, energy, and food nexus.

Furthermore, this study provided insights into the EU's legal framework concerning water-related challenges within the nexus perspective. The overarching objective of this paper is to engage with stakeholders in enhancing the coherence of policies related to the Water-Energy-Food Nexus. It endeavoured to explore noteworthy interconnections among policies already implemented under the nexus approach, examining correlations, developments, actions, and directives aimed at realizing the projections outlined by the Agreement.

Starting from the Energy-Food Nexus, the analysis indicated the vital–need for integrated and sustainable approaches to address the shared challenges of ensuring energy security, promoting agricultural productivity, and achieving food system resilience in the face of global environmental and socioeconomic changes. An example of a policy aimed at this nexus is the development of bio-gas production structures from waste resources and the funding of agro-photovoltaic structures on farms.

The Water-Food Nexus analysis revealed that understanding and managing this interconnection is imperative for devising sustainable strategies that address the dual challenges of ensuring water availability for agriculture and maintaining a resilient and secure global food supply. This Nexus has been addressed in water policies, for example, by the emphasis on the sustainable use of pesticides in agricultural practices.

Lastly, the Water-Energy Nexus underscores the mutual influence and vulnerabilities between water and energy, where changes in one system have direct implications for the other. Climate change, population growth, and increasing energy demands further amplify the complexities within the water-energy nexus. Managing this interconnection is paramount for achieving sustainability goals, optimizing resource use, and enhancing resilience in the face of evolving environmental and societal challenges. An example of this Nexus is the creation of water digitalization policies that regulate the use of water in data centers for cooling purposes.

Summarizing, this paper, is expected to contribute to fostering policy coherence across the realms of water, energy, and food, thereby supporting the transition towards a circular and low-carbon economy in Europe.