Carbon Footprints in the Production of Animal Products in the Context of the Obligation to Report It

Abstract

The aim of the paper was to analyse the genesis of the idea of carbon footprint (CF) reporting, the current EU regulations in force in this regard, and to provide a concrete example of practical measures in poultry production. The CF is the total sum of greenhouse gas (GHG) emissions generated directly or indirectly by an organisation, product, service, event or human activity, expressed as a CO₂ equivalent. Livestock production accounts for 12% to 14.5% of global methane and nitrous oxide emissions. GHG emissions from livestock production are closely linked to the species of animals; the highest CF values apply to products derived from ruminants, but poultry is also considered an environmental threat, inter alia due to the production scale. The CF of poultry production is not uniform and depends on many factors, including the farm location and climatic conditions of the region, the profile of production, its stage, the birds feeding and CF method of analysis. Industrial development is a continuous process that must align with the principles of sustainability and EU climate policy; therefore, it is necessary to look for and implement solutions to reduce its emissions in line with evolving European legal standards.

1. Introduction

Estimating, analysing and reducing the carbon footprint is part of the concept of sustainable development of companies in all industries. As pointed out by [1] following [2], the first mention of the term “carbon footprint” appears in the press in 2000 and is now widely used, although still without any legal definition. Definitions vary depending on the approach to be taken, and on greenhouse gases that should be included in the carbon footprint assessment, as well as on the degree of detail to be applied [3]. Kijewska and Bluszcz [4] have suggested a universal definition of “carbon footprint” as the effect of a functional unit of climate based on a specific metric which considered all relevant sources of emissions, removals and storage, both during consumption and production, within spatially and temporally defined system boundaries [5]. Kulczycka and Wernicka [6] proposed the definition of “carbon footprint” as the total amount of CO₂e (carbon dioxide equivalent) and other greenhouse gases with regard to emissions resulting from the product’s life cycle, including storage and neutralisation. Kołaczek [7] states that this is the total sum of greenhouse gas (GHG) emissions caused directly or indirectly by an organisation, product, service, event and even the activity of individuals, households or cities [8]. Therefore, it is a value that combines emissions of all greenhouse gases into a single number expressed as an equivalent quantity of carbon dioxide (eq. CO₂).

According to ISO 14067:2018, the carbon footprint of the product is the sum of GHG emissions and removals, expressed in carbon dioxide equivalent and is based on a Life Cycle Assessment using a specific category of climate change impacts [9]. The carbon footprint is assumed to be the total greenhouse gas (GHG) emissions caused directly and indirectly by a person, organisation, event or product, expressed in units of mass of CO₂e [8,10]. It constitutes a measure of the impact that a particular process or product has on climate change or determines the extent to which that process or product consumes Earth’s resources. This serves to reduce the impact of activities or to compare elements in order to choose an alternative with less environmental impact. The carbon footprint considers not only emissions directly generated by a particular activity or product, but also emissions generated at all stages of their life cycles.

2. The Concept of Sustainable Development

The first mention of the concept of “sustainable development” was used as early as in 1713 by German forester Hans Karl Carlowitz, to advocate the need to sustainably maintain a forest stand. This approach, close to our modern understanding, spread rapidly as a common practice since at the time the occurrence of felling of as many trees as would not exceed their natural growth took place. However, it took some 250 years before the need for sustainability was recognised in other economic sectors as well. Ultimately, the concept of sustainability emerged as a result of political, ideological and cultural changes at the turn of the 1970s. It can be perceived as an attempt to find a compromised solution between the desire to continue socio-economic development and the need to take limits to growth seriously. Over time, the concept evolved from a mere political slogan into a strategy for actual action [1]. Today, sustainable development is a constitutive element of strategic development programmes on global, national, regional and local scales.

The first global conference on the environment was organised under the UN patronage in 1972 in Stockholm under the slogan “Only One Earth”. Within its framework, environmental protection was elevated to the level of a primary function of the state, the term “environmental policy” was coined, and the need was pointed out to establish a UN specialised agency for environmental issues (UNEP). On 16 June 1972, the Declaration of the United Nations Conference on the Human Environments was adopted, consisting of an introduction and 26 principles. The concept is, as a rule, based on the assumption that sustainable development is based on such foundation as the economy, society and environment (ESG), which should include a single political context. Sustainability should be considered account especially in economic development strategies that seek to foster “genuine” prosperity and quality of life, improve the quality of the environment and the rational use of natural resources, ensure social equality (also for future generations) and build democratic institutions.

Also in 1972, the Club of Rome, a think tank investigating and publicising global issues, published a report titled “The Limits to Growth” [11]. It highlights the relationship between population growth and overly fast use of renewable and non-renewable natural resources. The possible scenarios were detailed, pointing to the imperfection of the model used to create them. Sustainable development was defined in 1987 in the Report of the World Commission on Environment and Development: Our Common Future (named the “Brundtland report” after the President of the Commission), as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs”. It aims to ensure economic development while safeguarding social and environmental sustainability. It can be assumed that, in a broad sense, sustainable development is correctly defined by Lawn [12], who states that “a nation is achieving sustainable development if it is undergoing a pattern of development that improves the total quality of life of every citizen, both now and into the future, while ensuring its rate of resource use does not exceed the regenerative and waste assimilative capacities of the natural environment”.

3. Legal Regulations on the Carbon Footprint—A European Union Perspective

In the 1990s, the global efforts to combat climate change have taken the form of the United Nations Framework Convention on Climate Change (UNFCCC/FCCC). The Convention was signed at the Earth Summit (United Nations Conference on Environment and Development) in Rio de Janeiro in 1992. The programme was developed to save the planet and the “Agenda 21” contains near 500 pages and 40 chapters. Today, a total 198 countries are Parties including 165 signatories. The UNFCC did not initially include obligations to reduce GHG emissions, but over time protocols were established setting their limits. These include the Kyoto Protocol (in 1997, Protocol to the United Nations Framework Convention on Climate Change), the Paris Agreement (adopted by 196 Parties at the UN Climate Change Conference (COP21) in Paris, France, on 12 December 2015, entering into force on 4 November 2016) and the Katowice Rulebook (the Katowice Climate Change Conference-COP24, Katowice, Poland, 2018). The Kyoto Protocol is an international treaty supplementing the United Nations Framework Convention on Climate Change, negotiated in December 1997, effective on 16 February 2005 and expired on 31 December 2012. The European Union, along with Norway, Iceland, Monaco, Switzerland and Liechtenstein associated in the European Economic Area, have committed to extend their obligations under the treaty until 2020.

Under the Kyoto Protocol, countries accounting for 18% of global emissions have committed to reducing their GHG emissions in comparison with 1990 in two commitment periods: 2008–2012 by approx. 5% and 2013–2020 by approx. 20%. The measures necessary to meet these commitments were introduced in 2007 as the climate and energy package by 2020, which, apart from the above-mentioned GHG reduction, sets a 20% target for energy efficiency improvement and 20% for energy generation from renewable sources by EU Member States. Subsequent changes brought about an increase in the pace of change and a new climate and energy framework applicable in the period 2021–2030: a GHG emission reduction of at least 40% (compared to 1990), a share of renewable energy of at least 32% and an improvement in energy efficiency of at least 32.5%. By reducing GHG emissions, the EU wants to achieve the goal of transformation towards a climate-neutral economy [13]. The Paris Agreement adopted at the United Nations Framework Convention on Climate Change (COP21st Conference of the Parties in Le Bourget, 30 November–12 December 2015) is described as the first ever legally binding and universal agreement on climate. The agreement was aimed at keeping the increase in global average temperature below 2 °C above the level recorded in the industrial era, with the tendency to limit this increase to 1.5 °C. The principles of implementing the Paris Agreement were established as part of the COP24 conference in Katowice (2018) and developed in the Katowice Climate Package (Katowice Rulebook).

Countering climate change is one of the most important challenges for the international community today. Politicians, scientists and citizens around the world see an urgent need to implement climate change mitigation policies to keep the global average temperature growth rate below 1.5 °C, demanding concrete action from authorities. Therefore, most countries around the world are preparing plans and implementing specific solutions. The European Union has ambitious targets set in this respect, and in the context of the European Green Deal [14] and European Climate Law [15], it has set itself the objective of reducing national net greenhouse gas (GHG) emissions by at least 55% by 2030 compared to 1990 levels and of achieving climate neutrality (zero net greenhouse gas emissions) by 2050 [16]. According to the European Commission’s 2050 long-term strategy, the Community aims to achieve climate neutrality by 2050 by creating net-zero greenhouse gas economies in the Member States.

On 14 July 2021, the European Commission put forward a package of legislative proposals (known as “Fit for 55”; [17]), covering climate, energy, land use, transportation and taxation, that will lead the EU to achieve its 2030 greenhouse gas reduction target. A number of major initiatives of the ‘Fit for 55′ package have been adopted so far.

At the global level, all the G20 countries, collectively responsible for about 75% of current global greenhouse gas emissions, have decided to set a target date by which they will become net-zero emitters (https://www.un.org/climatechange/net-zero-coalition, (accessed on 20 January 2026)). The United States, Canada, Brazil, Australia, and the European Union [15] have committed to achieving climate neutrality by 2050, China and Saudi Arabia by 2060, and India will strive for net-zero emissions by 2070 [18].

All Parties to the Paris Agreement under the United Nations Framework Convention on Climate Change (UNFCCC), 21st Conference of the Parties in Le Bourget, 30 November–12 December 2015) are obliged to prepare emission-reduction commitments known as Nationally Determined Contributions (NDCs). Pursuant to the Paris Agreement Transparency Framework, all Parties must report bottom-up inventories of national greenhouse gas emissions and track progress in implementing and achieving their respective NDCs. This report is to be included in the Biennial Transparency Reports (BTRs), which are to be submitted for the first time by the end of 2024. The parties may submit their inventory reports as part of the BTR or separately, while the countries listed in Annex I6 must continue to submit their inventory reports annually. Bottom-up national emission inventories are therefore an important element in reporting and tracking progress towards achieving the objectives of the Paris Agreement. However, national inventory reports are not yet available for all countries and years. Moreover, they are dependent on individual national reporting processes and methodological choices, may have incomplete data for specific sectors, and currently, with the exception of the Parties from Annex I to Report of the Conference of the Parties on its 21st session, held in Paris from 30 November to 13 December 2015, COP21, there is no obligation to include long-term series of emissions until the last year. To overcome these limitations and complement national inventories, an internal database was created: the Emissions Database for Global Atmospheric Research [19]. It has the feature of generating up-to-date emission estimates that are comparable between countries. EDGAR relies on several sources of international statistical data, the most important of which is the International Energy Agency (IEA).

On 16 December 2022, Directive (EU) 2022/2464 of the European Parliament and of the Council, amending Regulation (EU) No 537/2014, Directive 2004/109/EC, Directive 2006/43/EC and Directive 2013/34/EU with regard to corporate sustainability reporting (CSRD), was published [20]. The original scope of the Directive extended sustainability reporting obligations to approximately 50,000 companies listed in the EU or conducting significant activities within the Union, irrespective of their registered office. Under the CSRD, these entities were required to disclose substantially more comprehensive information on sustainability performance than under previous legislative frameworks. Initially, the obligation was to apply from the 2024 financial year, beginning with entities already covered by the Non-Financial Reporting Directive (including listed companies in Poland), and subsequently extending to other entities, including small and medium-sized enterprises. Member States were granted 18 months to transpose the Directive into their national legal systems. In Poland, this process was completed—albeit with a six-month delay—by the Act amending the Accounting Act and the Act on Statutory Auditors, Audit Firms and Public Supervision, signed by the President of the Republic on 12 December 2024. However, subsequent legislative developments at the EU level have significantly altered both the scope and the implementation timeline of the CSRD. In particular, Directive (EU) 2025/794 (“Stop the Clock”) postponed the application dates [21], while Directive (EU) 2026/470 (“Omnibus I”) introduced a substantial narrowing of the personal scope of the regulation [22]. Under the revised framework, the CSRD now applies only to companies exceeding EUR 450 million in net turnover and employing more than 1000 employees. Moreover, the reporting timelines have been deferred: in-scope EU companies are required to begin reporting in 2028, based on data for financial years starting on or after 1 January 2027, while non-EU parent companies will be subject to reporting obligations from 2029. Consequently, Member States are now required to transpose the amended CSRD provisions by 19 March 2027. Although Poland formally completed the initial transposition of the CSRD in December 2024, the national legal framework will require further adjustment in order to align with the modified deadlines and the reduced scope of application introduced by the “Stop the Clock” and “Omnibus I” legislative packages.

The Greenhouse Gas Protocol (GHG Protocol) is a global standard for measuring and managing greenhouse gas emissions, intended for both private and public entities. It is also a toolkit to help companies measure greenhouse gas emissions and assess the effects of projects aimed at mitigating climate change. The gases that generate the greenhouse effect are carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), sulphur hexafluoride (SF6) and hydrofluorocarbons (HFCs) and perfluorocarbons (PFCs) [23]. For each of these gases, it is possible to attribute the global warming potential (GWP) indicator measured per one molecule of carbon dioxide. The GWP is an index that quantifies the impact/potential global warming effect of 1 kg of a specific greenhouse gas over a century, compared to the value achieved by 1 kg of carbon dioxide. Although carbon dioxide is not the strongest greenhouse gas, it is the largest contributor to global warming due to its emissions. The GWP therefore compares the impact of a given greenhouse gas to that of CO₂ [24].

Carbon footprint is a type of ecological footprint. It is the total sum of greenhouse gas emissions caused directly or indirectly by a given entity, i.e., a person, organisation, event, product or branch of manufacturing. Carbon footprint is a measurable indicator that can be calculated for a company, specific product, service, process, organisation, country or region. There are two ways to express the carbon footprint (kilograms or tons of carbon dioxide), and the measure is tons of carbon dioxide equivalent (tCO₂e). It allows comparing emissions of different greenhouse gases using the same scale, i.e., considering the CO₂ content [25]. Calculations of greenhouse gas emissions for organisations are carried out according to the ISO 14064-1:2018 standard [26] and on the basis of the GHG Protocol methodology.

Currently, the methods for calculating the carbon footprint depend on the functional unit the footprint is related to and its scale. A carbon footprint calculated at the level of a company or product covers emissions caused by all activities related to the economic activity of the company, including energy consumption of buildings and transport. The CF indicator level of a product includes emissions caused by the extraction of the raw materials from which the product is made, emissions from the production process, use and storage or recycling after use. To sum up, the carbon footprint is calculated for all activities that involve energy consumption, processes that may release greenhouse gases into the atmosphere, and the consumption of materials and products.

4. Sources of Carbon Footprint

Recently, there has been a marked increase in the demand for information about the sustainability of businesses, especially from investors. This is due to the volatile nature of risks for individuals and the growing awareness of investors about the financial consequences of these risks. This applies to climate-related financial risks. There is also growing awareness of other environmental issues, such as biodiversity loss, as well as health and social issues, including child labour and forced labour.

The increase in demand for information on sustainability is also a result of the expansion of the segment of investment products, which are clearly linked to meeting certain sustainability standards or objectives and ensuring consistency with the level of ambition of the Paris Agreement as part of COP21, Convention on biological diversity (CBD, opened for signature at the Earth Summit in Rio de Janeiro on 5 June 1992 and entered into force on 29 December 1993) and EU policies. The increase in demand is also partly a logical consequence of previously adopted EU legislation, in particular Regulation (EU) 2019/2088 [27] and Regulation (EU) 2020/852 [28]. Information on environmental impact is also important in the context of mitigating future pandemics, as human disruption of ecosystems is increasingly linked to the occurrence and spread of diseases.

The list of sustainability issues on which entities are required to disclose relevant information should be as consistent as possible with the definition of the term “sustainability factors” established in Regulation (EU) 2019/2088 [27], in order to avoid a mismatch between the information requested by data users and the information disclosed by entities. The list should also respond to the needs and expectations of users and units, who often use the terms “environmental”, “social” and “management-related” to assign these factors to one of the three main categories of sustainability issues.

The most popular methodology for carbon footprint calculation is the GHG Protocol developed jointly by the World Resources Institute (WRI) and the World Business Council for Sustainable Development (WBCSD). The GHG Protocol provides a framework for businesses to report and reduce their emissions in a consistent and transparent manner. According to this standard, the carbon footprint is divided into three scopes. Scope 1 covers direct emissions, i.e., data on the consumption of fuels such as natural gas, petrol, liquefied petroleum gas (LPG), coal, etc., data on industrial processes such as steam generation for technological purposes, emissions from refrigeration and air conditioning, and data from the car fleet owned by the company. Scope 2 covers emissions resulting from the consumption of electricity, heat, process steam, and cooling purchased or delivered from outside. Scope 3 covers indirect emissions occurring in the supply chain (categories: purchases of goods and services, emissions related to the production of capital goods), fuel- and energy-related activities (not included in Scope 1 and Scope 2), transportation and distribution (upstream), waste from operating activities, business travel, daily commuting of employees, leased assets (upstream), transportation and distribution (downstream), processing of sold products, use of sold products, end-of-life treatment of sold products, leased assets (downstream), investment assets and other emissions not included in other Scope 3 categories.

With the current level of public awareness, although emissions classified as Scope 3 often constitute the largest part of a company’s carbon footprint, they are often impossible to calculate because of the need to involve entities in the supply chain cooperating with a given company in obtaining data. Companies should focus especially on calculating Scopes 1 and 2, which refer to the direct emissions of a given company, which can be helpful for further analysis and implementation of emission-reduction strategies, which often becomes a market requirement for companies cooperating with major customers.

Emission factors are required to calculate emissions, which give the number of emissions generated by the combustion of fuel by the entity and its other activities that generate them. In Poland, the primary source of emission factors is KOBIZE (Krajowy Ośrodek Bilansowania i Zarządzania Emisjami [National Centre for Emissions Management). For multinational companies, tables specific to the country of registration of the parent company can be used as a source of emission factors for corporate reports, e.g., DEFRA (Department for Environment, Food and Rural Affairs) for companies based in the UK and Climate Registry for companies based in the US. Emission factors are also published by international organisations such as the IEA, often with paid access, which discourages companies from using them. Due to the absence of a single international standard that would define emission factors, companies often provide source references in their reports.

5. Decarbonisation Goals and Strategy in Industry

The EU climate policy forces businesses to actively participate in the fight against climate change due to its high reduction potential. One of the pillars of this policy is to reduce greenhouse gas emissions by as much as 55% by 2030 compared to the 1990 level.

The most popular methodology for setting decarbonisation targets at the moment in the market is the methodology developed by the Science-Based Targets Initiative (SBTi), which bases its foundations on the Paris Agreement from 2015. The SBTi decarbonisation target guidelines include several key elements, and are designed to ensure the consistency, credibility and effectiveness of the decarbonisation targets of companies that make relevant commitments. Decarbonisation targets should be consistent with the Paris Climate Agreement goals of limiting global warming to less than 2 °C compared to pre-industrial era levels (the upper limit of temperature increase considered necessary to protect ecosystems and communities worldwide). There should also be a direction for decarbonisation set for a specific period including short, medium and long-term targets.

Since decarbonisation targets should include the reduction in greenhouse gas emissions across all operations of the company, they should be set in all three previously mentioned emission scopes (Scopes 1 to 3). These targets should be ambitious, but, at the same time, realistic and based on scientific models and scenarios that take into account the impact of emissions on climate change. SBTi adopts the following:

• Well Below 2 Degrees (WB2D) scenario: Companies had the opportunity to report this scenario until 2021, when the SBTi withdrew the possibility to report such targets in favour of a more ambitious 1.5 °C target; the WB2D scenario was based on the Paris Agreement goal, which aims to limit global warming to below 2 °C compared to pre-industrial era levels. The WB2D scenario sets out greenhouse gas emission-reduction pathways for different sectors to achieve this target.
• The “1.5 Degrees Celsius” (1.5 °C) scenario: This scenario is more ambitious and aims to limit global warming to 1.5 °C. The 1.5 °C scenario describes a more ambitious approach to reducing emissions for sectors that have the greatest impact on climate change.
• Sector scenario: SBTi also provides emission-reduction scenarios for specific sectors of the economy, such as energy, heavy industry, transport, construction, etc. Each sector has its own targets and reduction paths, which are tailored to its specificity and technological capabilities.
• Scenario related to Gross Domestic Product (GDP): Some SBTi scenarios also take into account the link between emission reductions and economic growth. Businesses may set decarbonisation targets that relate to the intensity of emissions in relation to GDP, which allows to take economic growth into account while reducing emissions.

The process of calculating emissions in all three scopes discussed above is crucial from the point of view of deciding on the sequence of actions, scale and necessary resources. Smaller businesses should focus on reducing Scope 1 and Scope 2 emissions, while bearing in mind the importance of Scope 3 emissions (all emissions generated outside the company’s control, e.g., in the supply chain)—in the FMCG industry, this is usually where more than 90% of emissions are located [29].

6. Reporting of the Amount of Carbon Footprint

Although the issues of carbon footprint reporting have been so far required mainly by the market from companies located in the supply chains of companies leading in environmental awareness issues, now the carbon footprint reporting, due to the Corporate Sustainability Reporting Directive [20], will become mandatory as early as 2026 (for 2025) for large enterprises (employing more than 250 employees and exceeding the relevant turnover threshold), and for listed companies already in 2025 (for 2024), while SMEs (small and medium enterprises) will be subject to CSRD reporting requirements in 2027 (for 2026).

The CSRD on nonfinancial reporting implements a package of new standards called the ESRS (European Sustainability Reporting Standards) containing, among other things, a package of indicators related to the reporting of greenhouse gas emissions. Under the CSRD, companies will be required to report their greenhouse gas emissions, both direct and indirect. The CSRD and the aforementioned GHG Protocol are mutually complementary. The CSRD introduces compulsory sustainability reporting, including GHG emissions, while the GHG Protocol provides standards that companies can use to measure, report and reduce these emissions. In this way, the GHG Protocol supports the implementation of the CSRD, making it easier for enterprises to meet the new requirements for transparency and accountability on climate issues [30].

Pursuant to Articles 19a (1) and 29a (1) of Directive 2013/34/EU, undertakings are required to disclose information in five areas of reporting: business model; policies, considering the due diligence processes in place; outcome of these policies; risk management; and key performance indicators related to the activity.

Disclosure of this information is likely to have positive effects in terms of business transformation, and the basis of the legislature’s action is to generate changes in the strategy of enterprises. Clear effects may also be seen on capital markets. The reports provided under the CSRD will provide investors with more consistent and comparable data that will be used to value companies. The assessment of the performance of the management staff may depend on the companies’ performance in terms of sustainable development.

7. Carbon Footprint Reduction Methods

Examples of reduction methods under the strategy of decarbonisation of enterprise’s own emissions (Scopes 1 and 2) include:

• Increasing the share of renewable energy sources (RES) in the company through investments in photovoltaic installations, wind power plants, solar panels, as well as purchase of renewable energy from external sources, replacement of energy and heat generation sources [31].
• Sustainable transportation: Auditing the transport fleet and identification of ways to reduce transport-related emissions. Introduction of a policy to use low-emission or hybrid vehicles (charged from RES). Encouraging employees to use public transportation, carpooling and bicycles, and installing RES charging stations at their buildings [32].
• Developing a waste management programme, including recycling, waste segregation, reduction in packaging consumption and optimising production processes to reduce waste, as well as a closed-loop economy, with the use of post-production waste such as chicken manure or other organic waste in, e.g., a biogas plant [33].
• Engaging employees and business partners to actively participate in the company’s decarbonisation initiatives through educational programmes [34,35], training sessions, competitions, awards and awareness campaigns. Supporting them in undertaking pro-environmental activities, including outside the workplace. Concurrently, looking for opportunities to eliminate emissions, e.g., in the area of transport waste or transportation itself in cooperation with suppliers and customers.
• Energy efficiency, which, although mentioned as the last item, is at the top of the to-do list. Examples of these activities include the introduction of environmental management programmes and systems for improving energy efficiency, including energy audits, equipment upgrades, process optimisation, and employee training to raise energy awareness. Striving towards reduction in energy consumption and emissions associated with its generation. It is a good practice to carry out annual inspections of installations and equipment and to search for new, more effective solutions [36,37]. There are incentives for this type of initiative in Poland in the form of white certificates issued by the Energy Regulatory Office (Urząd Regulacji Energetyki) for improving energy efficiency.

Examples of activities related to the improvement of energy efficiency include improving the energy efficiency of production and production-related processes and eliminating energy waste from processes through [37,38], for example:

• Conducting an energy audit to identify inefficient sources of energy consumption;
• Reducing compressed air leaks;
• Changing the organisation of work, e.g., from a three-shift to a two-shift system;
• Changes the way of machinery handling (commonly known as start-up scenarios), e.g., during meal breaks;
• Changing employees’ habits in everyday functioning in the company;
• Reducing the temperature of washing water and process water (if possible);
• Recovering heat from the installation, e.g., from compressors, economisers on chimneys at furnaces, from condensate, and using it, for example, to heat a building;
• Optimisation of production processes in terms of product sequences;
• Thermal insulation of installations;
• Revision of energy tariffs and elimination of reactive energy;
• Replacement of condensers with more efficient ones;
• Use of modern energy generation technologies for producing energy required in the production process, e.g., heat pumps supported by RES solutions.

Another group of solutions are methods of modernising production plants to increase energy efficiency [39,40,41], e.g.,:

• Walls and roof thermal modernisation;
• Window replacement;
• Modernisation of the heating system, e.g., replacement with heat pumps;
• Replacement of lighting with low-emission (LED-type) lighting;
• Use of motion sensors;
• Installation of systems for remote management of buildings;
• Switching to greener fuel sources—replacing heat and power sources from coal or fuel oil with biofuels or natural gas, and preferably electric ones powered by RES.

8. Carbon Footprint Emissions and Ways to Reduce Them Based on Poultry Production

The problem of climate change is not a new issue, with the first research in this area dating back to the 19th century [42]. With the intensification of production in almost all agricultural sectors, however, the problem has begun to grow. The most frequently addressed issues in the context of climate change are emissions of greenhouse gases, which, according to the definition, are gaseous components of the atmosphere of various origins that are capable of retaining and subsequently re-emitting infrared radiation. The estimated carbon dioxide equivalent (CO₂eq) allows the assessment of the degree of interference in atmospheric composition caused by the manufacture of a given product and its global impact on the environment, and to compare, in this respect, different products with one another [43].

The role of the agricultural sector in terms of emissions is fairly well understood, although there are significant differences depending on the study, mainly due to the research methodology used. Some of the papers analyse this environmental impact of agricultural production as a total figure combining energy costs and emissivity directly from agriculture, presenting it as the sum of emissions from all stages of production [44] according to the “from farm to fork” principle or analysing only the direct impact of animals [45]. In the EU alone, agricultural production is responsible for the production of 54% of methane and more than 70% of nitrous oxide [46], thus gases with a significant impact (CO₂eq 28 and 298 kg CO₂ respectively). The livestock production alone is a very significant source of GHG emissions, accounting for 12% to 14.5% of their global emissions [47], with enteric fermentation accounting for the largest share of emissions from the livestock sector (39.1%), followed by the use and storage of manure (16.4%). The management of manure and fertilisers combined generates 33.6% of greenhouse gas emissions from livestock production, mainly nitric oxide. Emissions from feed production (13.4%), land-use change (9.2%), emissions from off-farm processes (2.9%), and direct and indirect energy (1.8%) are also important [48].

The carbon footprint is the total amount of greenhouse gases produced during the product life cycle, expressed in CO₂ equivalent. For the agricultural sector, defining clear boundaries is somewhat more complex than for typical products, so the methodology for determining this ecological footprint is more complex [49]. Some problems are also related to the definition of the product life cycle and the fact that the agricultural sector very often has more than one direction of use (co-production). Moreover, as already mentioned in the production of greenhouse gases, the level of emissions varies significantly due to the type of production carried out. Greenhouse gas emissions from livestock production are closely linked to the species of kept animals. Lesschen et al. [50] formulated a series depending on the volume of emissions and species, respectively: beef → pork → poultry meat → table eggs → milk. There are regional differences in this respect, but in general this trend continues across the European Union. The high importance of beef production is closely linked to methane emissions from fermentation in polygastric animals. Methane is also characterised by a relatively high impact on the greenhouse effect (1 kg CH₄ = 28 kg CO₂eq). In general, the highest carbon footprint values are obtained for products from ruminants. According to Zarczuk and Klepacki [9], lamb rank highest, followed by beef and dairy products. In this ranking, the poultry sector products are much further away. Nijdam et al. [49] also reached similar conclusions, pointing out that both poultry meat and eggs had a relatively low carbon footprint (2–6 kg eq CO₂/kg of product). In comparison, the values for beef were as high as 129 kg eq CO₂/kg and for pork 4 to 11.6 kg eq CO₂/kg of product.

The poultry industry is one of the branches of animal production that has a strong impact on the natural environment. This is mainly due to the emission of gases (ammonia, nitrogen dioxide, methane and carbon dioxide), dust and odours, but also to the significant nitrogen and phosphorus content in bird brood. In the context of carbon footprint, one of the main environmental risks caused by poultry production is gas emissions.

As mentioned above, the effect of poultry production on the GWP is relatively small, but due to the scale of this production globally, this effect is relatively significant. The most common policy for assessing the impact of poultry production on the environment and climate change is Life Cycle Assessment (LCA), which includes a number of variables directly related to both production and all elements necessary for the production and processing of poultry raw materials. Analyses of the main areas where there is a significant increase in the contribution of poultry production to the greenhouse effect point to the production and logistics of feed, especially protein feed based on soybeans [51]. Due to the need to ensure the right amount of raw material, land-use changes (LUCs) take place, generating an increase in the GWP value for poultry production. According to MacLeod et al. [52], LUC is responsible for 18% of greenhouse gas emissions from broiler chicken production.

The variables taken into account in life cycle examination include, in addition to the burden related to feed production, the environmental costs of chick production, the burning of fossil fuels for logistics and transport of means of production, and the direct consumption of these fuels for keeping proper microclimatic conditions in poultry houses, as well as the management of resulting manure. Slightly different characteristics apply to the production of table eggs. The longer rearing period and the need to obtain a productive flock (raising hens) and the need to manage cockerels makes the environmental cost of obtaining eggs relatively high. The common research approach to analysing the environmental burden of rearing and breeding under the farm to fork policy, despite being standardised, gives rather divergent results (

Table 1. Emissions in various aspects of poultry meat production.

Research Material	GWP Figure (kg CO2eq/kg Live Weight)	Notes	Source
Chicken broilers	2.70	Life Cycle Assessment in the modern poultry farm	[53]
	3.37 *	The assessment depending on the final body weight: 3.03 CO2-eq/kg live weight for light birds; 3.25 CO2-eq/kg live weight for middle heavy birds; 3.84 for heavy birds, respectively	[54]
	1.33–1.62	The assessment depending on microclimate condition (various positive pressure values) and rearing system (conventional vs. organic)	[55]
	17.40	Life Cycle Assessment	[56]
Slaughter turkeys	3.63	Life Cycle Assessment	[57]
	3.99–4.57	Comparative analysis depending on birds’ sex and ventilation system (regulated vs. natural)	[58]
	4.24	Life Cycle Assessment, without manure assessment	[59]

* The average of authors’ measurements, GWP—Global warming potential.

and

Table 2. Emissions in various aspects of poultry egg production.

Research Material	GWP Figure (kg CO2eq/kg Live Weight)	Notes	Source
Chicken eggs	2.3 kg CO2-eq/kg of eggs	Value determined for a standard egg-laying hen diet; the study has also analysed the effect of changing the diet on the change in the GWP figure	[60]
	1.9–2.5 CO2-eq/dozen	Life cycle analysis according to the number of enterprised farms, GHG was increasing with number of enterprise farms	[61]
	1.14 kg CO2-eq/kg of eggs	Life Cycle Assessment	[62]
	0.797–0.829 kg CO2-eq/kg of eggs	Depending on the system of bird keeping (conventional vs. organic), Recipe2016 Method	[63]
	1.35 kg CO2-eq/kg of eggs	Analysis of available statistics and surveys	[64]
	1.164–1.479 kg CO2eq/kg of eggs	Analysis of farms over various years with the use of a GHG calculator	[65]

) due to the rearing technology used, the species of birds kept, their final body weight and other criteria.

The need to reduce the carbon footprint of poultry production has led to comparative studies within bird rearing systems for both broiler chickens [66] and laying hens [67]. Generally, lower GWP values occur in open systems. Simultaneously, given the need to provide additional space for poultry ranges, such solutions are of local rather than global importance, and on a wider scale, the effect of land-use change could increase the GWP of such systems.

Although birds do not produce methane during the digestive process, it is still produced by microbiological changes in litter and manure [68]. Manure management is one of the underestimated and environmentally significant sources of GHG. According to data presented by Zhu et al. [69], with the storage time of manure from laying hens, nitrogen is lost through the release of ammonia (the highest rates for all the groups under analysis) and nitrous oxide (N₂O). For the latter gas, intensive microbiological processes occur primarily at the initial stage of its storage. Research indicates that its amount is strictly dependent on a number of conditions in the poultry house and directly in the litter, such as humidity, temperature, or pH.

However, the relatively short production cycles and the amount of litter used make the methane emissions from poultry farms relatively low, at least at the production stage [70]. The manure management is problematic because the conditions in the heap may favour not only methane generation but also processes related to nitrogen availability, i.e., nitrification and de-nitrification. The final result is that nitrous oxide can be released into the atmosphere. Research in this area clearly show that the use of natural fertilisers, including manure, significantly increases N₂O emissions from soil [71]. However, it is possible to minimise nitrogen loss and the negative impact of manure application on increasing emissions of nitrous oxide by using it at the right times or improving the C:N ratio. The largest methane emissions among all livestock are observed in cattle [72], which are responsible for the production of approx. 84% of animal enteric methane produced intestinally [73]. In laying hens, the emission of this gas ranges between 0.02 and 0.08 kg per laying hen per year, while the emission of nitrous oxide by these birds is next to zero [74].

Since the emission of harmful gases mainly includes the products of microbiological transformations in the litter, it is the litter that undergoes the most important modifications. The simplest way to reduce microbiological transformations is to regulate humidity by using watertight watering lines and to ensure optimum stocking density, which can also intensify these processes [75]. The amount of ammonia being released is influenced by the type of specific bedding material (straw, pellets, others) [76] and potential litter additives. The means that are used most often for this purpose include physicochemical practices [77], substances of plant origin [78], or aluminosilicates, the effect of which has already been demonstrated for various species of poultry [79,80,81].

Ammonia emissions can be controlled by feeding the flock with feed with reduced levels of crude protein and synthetic amino acids [82]. Certain feed additives can also be effective in this regard. According to Mahardhika et al. [83], the use of probiotics both in litter and in the diet of birds had a positive effect on the reduction of ammonia emissions, which indicates a reduction in the intensity of microbiological transformations in the litter, which also translates into the emission of other gaseous pollutants. Of particular note is the addition of Yucca schidigera, where it has been observed that adding it to broiler chicken feed can reduce the ammonia content in the litter by up to 17% on the 37th day of rearing [84]. Less obvious additives include, among others, carbonaceous substances (Biochar) obtained as a result of biomass decomposition at high temperature and in an oxygen-free environment [85]. Regarding feed additives, however, it should be remembered that any such nutritional intervention must be at least neutral in the context of the physiology of birds and their production results.

However, it is not possible to completely eliminate emissions of nitrogen compounds, either at the stage of production facilities or later during the storage of the resulting manure. It is therefore necessary to look for alternative methods to maximise the reduction of not only pollution and GWP, but also to reduce nitrogen losses. Perhaps a solution is anaerobic fermentation in the biogas plant conditions. The studies by Beausang et al. [86] in this regard indicate the possibility of reducing the net environmental burden and significantly reducing the GWP.

To conclude, when assessing the emissions of poultry production, it should be noted that its carbon footprint is not uniform. It depends on a number of factors, including the location of the farm and the geographical and climatic conditions of the region [87,88,89], production profile [87,89,90,91], its stage [92,93], manner of bird feeding [94], and method of analysis [95].

9. Conclusions

The growing demand for food, coupled with the need to ensure the protection of the natural environment, constitutes a crucial element of a sustainable economy. Carbon footprint (CF) reporting is no longer merely a tool for green marketing or a voluntary commitment; it is becoming a key component of legal compliance and risk management strategy in modern enterprises, including the livestock production sector, particularly poultry farming.

The magnitude of the carbon footprint in poultry production—which, due to its scale, contributes to climate change and pollution—is highly variable and depends on a range of technological and environmental factors. A number of emission-reduction methods have been identified that can be applied at various stages of the production chain, ranging from feed and litter management, through improving energy efficiency, to manure management, for instance in biogas plants.

Despite the establishment of a unified reporting framework in the form of the European Sustainability Reporting Standards (ESRS), adopted under the Corporate Sustainability Reporting Directive (CSRD), a fully harmonised system of emission factors and uniform databases for calculating the carbon footprint is still lacking. Consequently, companies utilise diverse data sources and different calculation methods in practice, which limits the comparability of reports between entities operating in various EU Member States. To some extent, this phenomenon undermines the harmonisation objective underpinning the CSRD, which is to ensure a high level of transparency and comparability of nonfinancial information within the internal market.

A clearly observable trend, driven both by regulations and market expectations, is the shifting of responsibility towards indirect emissions (Scope 3). For the poultry industry, this entails the necessity of including emissions from feed production (including those related to land-use change), logistics, and processing in their reporting. This area is the most difficult to control, yet it simultaneously constitutes the largest portion of the total carbon footprint. The implementation of the CSRD marks a transition from voluntary to mandatory reporting, gradually covering not only large enterprises but ultimately also small and medium-sized entities within supply chains. This will compel agricultural producers and processors to implement emission monitoring and reduction systems in order to maintain their market position.

In light of current regulations, carbon footprint reporting extends far beyond a purely reporting function. Its added value for livestock production systems, including poultry, is multidimensional. It serves as a tool for process optimisation, enables economically rational investment decisions, and is a key element of competitive advantage. With growing consumer awareness, a low product carbon footprint is becoming a significant factor in supplier selection by major retail chains.