Regenerative Development Model: A Life Cycle-Based Methodology for the Definition of Regenerative Contribution Units (RCUs)

Abstract

In the “contributive” approach, balancing greenhouse gas (GHG) emissions cannot be considered comprehensive, as all footprints, such as ecological and water, shall be assessed and balanced by regenerative actions contributing not only to carbon removal, but also to the regeneration of biodiversity, land, and water. A survey on existing methodologies for the assessment of the damage (environmental burden) and the calculation of the environmental repair (offsets) has been presented in this work. Its outcome pointed out a lack of scientific knowledge on how to put metrics beyond the regenerative development model and in particular on how life cycle assessment (LCA) can scientifically support a number of key features essential to develop a new methodology. The proposed approach is based on three pillars: reduce, remove, and repair. Indeed, this paper aims to develop a methodological LCA-based approach for the definition of Regenerative Contribution Units (RCUs) to quantitatively assess the contribution of projects in line with Sustainable Developments Goals (SDGs) and the framework of regenerative model development. These regenerative units might be marketed locally and globally by enterprises interested in purchasing such assets to scientifically and ethically comply with their corporate ESG obligations. Furthermore, the novelty and feasibility of the proposed approach has been preliminarily investigated through an example of footprints balancing.

1. Introduction

The Intergovernmental Panel on Climate Change (IPCC), the United Nations body for assessing the science related to climate change, have recently finalized the Synthesis Report for the 6th Assessment Report during the Panel’s 58th Session (March 2023) [1]. According to this report, it is likely that global warming will exceed 1.5 °C during the 21st century due to a significant emission gap between global greenhouse gas (GHG) emissions in 2030 associated with the implementation of Nationally Determined Contributions (NDCs) announced prior to COP26 and those emissions related to modeled mitigation pathways that limit warming to 1.5 °C (>50%) with no or limited overshoot or limit warming to 2 °C (>67%) assuming immediate action (high confidence). Although many countries have committed to achieve net zero GHG or net zero CO₂ by around mid-century, these commitments differ across nations in terms of extent and specificity. Furthermore, to date, limited policies have been established to deliver on them [1].

As governments must strengthen their contributions to the COP21 Paris Agreement [2] and the COP26 Glasgow Climate Pact [3] to limit the worst effects of climate change, parallel initiatives have the objective of building momentum around the shift to a decarbonized economy. In particular, Race To Zero is a global campaign, led by the UN High-Level Champions, to mobilize a coalition of leading net-zero initiatives with the aim to achieve the net zero carbon emissions by 2050 at the latest [4]. These initiatives involve businesses, cities, regions, investors, and universities committing to implement a realistic plan for transitioning to zero for all GHG, while finding offsets for residual emissions. In the initiative’s intentions, offsetting do not substitute for or delay decarbonization and by the net zero target date and credits and sinks are only used to balance the hardest-to-abate emissions [4,5]. Yet, in reality, or at least during a transitional phase towards decarbonization, offsetting is the preferred option of organizations claiming carbon neutrality. One program that experienced significant growth in recent years was the voluntary carbon market (VCM), whereby individuals or organizations decide to pay for credits, representing GHG emission reductions or absorption occurring elsewhere in order to balance their carbon emissions. In 2021, the transactions related to voluntary markets increased from USD 520 million in 2020 to USD 2 billion, pointing out an exponential growth, as relevant evidence that net zero carbon pledges force companies and other actors to offsets to limit their emissions [6].

Despite its growth, the carbon offsetting has been often considered as a way to show a climate commitment, without actually making any real actions to reduce GHG [6,7,8,9,10]. Consequently, the carbon offsetting is receiving a great attention although with a negative connotation as considered closer to greenwashing lacking actual emission reduction efforts (referred as “environmental inaction”) [7] and it is strongly criticized when it became a way to pay in order to pollute (“buying forgiveness”) [8,9,10].

Notwithstanding the criticisms, carbon offsetting is considered a useful component of the regulatory and political solutions, for instance in order to mitigate the carbon footprint of industrial sector and to capture the excess amount of carbon currently in the atmosphere through tree planting [7,9].

Furthermore, the carbon offsetting lacks a widespread definition, including different notions, as emission avoidance, emissions that did not occur, or carbon sequestration, an increase in absorption capacity. For instance, the carbon neutrality cannot be attained at a company level, as all the supply chain and the business model shall be part of this decarbonization process [11]. Organizations and individuals can instead “contribute” to the global net-zero goal through their pledges. Thus, a terminology change, moving from climate offsetting to climate contributions, should be sustained to increase awareness of the real impact of balancing emissions. The Net Zero Initiatives (NZIs) defines climate contribution through supporting emission reduction projects and also providing clearness on the concept and its actual environmental and social impacts [12]. In this framework, the concept related to climate contribution goes beyond the environmental benefits, carbon absorption or avoidance, accounting for other benefits. For instance, climate contributions support the achievement of the United Nations Sustainable Development Goals (SDGs), which include positive social benefits, biodiversity, gender equality, among others. Consequently, this vision of sustainability extends beyond the environmental realm and emphasizes the interconnectedness of social and environmental well-being. Moreover, climate contributions surpass conventional sustainability practices as they aim to generate positive impacts and foster regenerative cycles that enhance the welfare of both human society and the natural world. They contribute to a significant transformation of the cultural model that shapes the agenda for achieving the SDGs [13].

Within the VCM, projects generating credits with additional non-carbon benefits (such as social and environmental ones) also demonstrated a growing market appeal. This trend might be ascribed to their characteristic in delivering non-carbon benefits such as positive returns for communities and the protection of biodiversity. Moreover, according to Ecosystem Marketplace, the growth of VCM is associated with the rising prices for nature-based credits for projects/activities (e.g., reforestation), “blue” carbon from coastal and marine ecosystem projects avoiding forest conversion. The largest share of trades (46%) is related to projects in the forestry and land use category, having the highest prices with a weighted average price in 2021 of USD 5.80 per ton, compared with a global benchmark 2021 price across the total market of USD 4.00 per ton [6]. Despite their importance, actually non-carbon benefits are listed in a qualitative way, without a real and tangible quantification of the impact, positive or negative, caused by projects generating carbon credits in the VCM. In fact, these projects may have not only a “neutral” impact on biodiversity, ecosystems or land use but often the territory and livelihoods of local actors may be impacted by carbon offsetting, in particular concerning land use and change in the ways of living and using territory and forests [14]. Furthermore, when calculating climate contribution, it is important to consider the context in which actions or projects take place [15,16]. For example, an activity reducing carbon emissions in a region with a high deforestation rate may have an even greater positive impact on climate change mitigation compared with a similar activity in a region with lower greenhouse gas emissions.

Shifting to organizations claiming to be climate neutral (PAS Carbon neutrality and Science Based Target), which need real, verifiable, credible, and sustainable credits generated by project developed in the VCM, it is important to point out that GHG calculation, both at organizational (GHG Protocol [17], ISO 14064-1:2019 [18]) and product level (PAS 2050 [19], ISO 14067:2018 [20]), requires solid scientific basis and shall also be comprehensive. Limiting to Net-Zero target to be reached at product level, a life cycle approach as a basis for calculating carbon footprints can help in developing decarbonization strategy avoiding carbon leakage, burden-shifting and greenwashing [21]. Furthermore, it is paramount to pursue the consistency between the assessment of the damage (environmental burden) and the calculation of environmental repair (offsets) [21]. The use of a consistent framework shall ensure the right assessment of the balance without inconsistent accounting rules. Consequently, the carbon offsetting schemes must be enhanced by including a life cycle perspective and consequently adequate accounting rules, which should be consistent with the carbon footprint calculation [21].

For this reason, the role of life cycle assessment (LCA) [22,23] in the context of decarbonization and carbon neutrality has been recently highlighted in the special issue entitled “Life cycle assessment in the context of decarbonization and carbon neutrality” [24]. It covers the following topics (i) consistent GHG accounting and assessment through LCA, emphasizing the challenges of double counting, the potential underestimation of environmental impacts, and the overestimations of beneficial effects of temporary carbon storage [25,26], (ii) the mitigation measures recently proposed in several sectors such as transport, building, and agricultural sector [27,28,29] as well as issues related to carbon emission offsetting [30]. Consequently, the topics currently addressed by the LCA community are limited to carbon footprint calculation and offsetting assessment, not accounting for other relevant impacts, such as ecological footprint and water footprint.

In the “contributive” approach, balancing GHG emissions cannot be considered comprehensive, as all footprints, sometimes interrelated but often having potentially opposite trends, shall be assessed and balanced by regenerative projects contributing not only to carbon removal but also to the regeneration of biodiversity, land, and water. So, despite the existence of wide scientific literature on LCA applied to several products and services, there is a lack of scientific knowledge on how LCA can support the regenerative development model. In fact, embracing the concept of climate contributions instead of carbon offsetting, there is the need of putting metrics beyond the regenerative development model, quantifying climate contributions at least in terms of carbon, ecological and water footprint and finding a method to balance these impacts with an equivalent amount of climate contributions, regenerated land and water. Moreover, as recently highlighted, the active carbon offsetting programs do not account for the entire life cycle but they focus on a single phase [31]. For instance, the renewable energy and energy efficiency methodologies consider the use phase only, the waste methodologies examine an improved end-of-life treatment, or the industrial gas methodologies focus on a modification of a single process [21,31]. Furthermore, most methodologies mentioned that negative environmental or social impacts could potentially occur although their quantification is overlooked.

The present work aims to present an innovative methodological LCA-based approach developed for the definition of Regenerative Contribution Units (RCUs) that could quantitatively assess regenerative development. After a deep survey of existing methodologies currently used for calculation of environmental burden and offsets, the paper illustrates the proposed methodology through a step-by-step approach. Lastly, its novelty and feasibility has been preliminary investigated through an example of environmental burden calculation through LCA and balancing with a potential regenerative project.

Consequently, the proposed methodology seeks to represent an innovative proof of concept delivering a contribution to the knowledge to act.

2. Holistic Approach toward Sustainable Development

Regenerative development, as a scientifically grounded approach, embraces interdisciplinary principles and methodologies to promote the restoration and enhancement of ecosystems, communities, and economies. Fundamental to this approach is systems thinking, which recognizes the intricate interdependencies and feedback loops among ecological, social, and economic systems [32]. This holistic perspective facilitates a comprehensive understanding of the complex relationships within these systems, enabling the identification and implementation of effective solutions.

Drawing from principles of ecological restoration, regenerative development prioritizes the rehabilitation of degraded ecosystems. Informed by scientific research in ecology, it employs strategies such as reforestation, habitat restoration and soil regeneration to restore ecosystem functionality, conserve biodiversity and mitigate the impacts of climate change.

The integration of social and behavioral sciences yields valuable insights into human behavior, social equity, and community empowerment. Informed by scientific research in these fields, regenerative initiatives strive to foster inclusive and participatory approaches, empowering local communities and promoting sustainable behaviors and lifestyles [33]. Aligned with the objectives of climate science, regenerative development takes proactive measures to address climate change. Scientific research in climate science informs the selection and implementation of emission reduction projects, ensuring their scientific rigor and contribution to climate stabilization. By integrating these scientific principles and knowledge from diverse disciplines, regenerative development adopts a rigorous and evidence-based approach. It leverages scientific understanding to inform strategic decision-making, enhance project effectiveness and maximize positive environmental, social and economic outcomes for ecosystems and communities.

Natural resources have traditionally been used at will without any limitation especially in the western cultures, and this idea has spread globally [34,35,36]. It was only in the 1970s and 1980s that there was increased attention towards sustainable development, with global reports emphasizing its necessity [37,38]. Sustainable design has gained momentum in the 1950s and 1960s with ecodesign and a focus on social justice, eventually leading to contemporary iterations that integrate both aspects [39].

Despite conceptual progress, there has been less progress in achieving sustainability goals. Furthermore, some scientists and professionals issue whether anthropocentric goals are suitable for improving the health of social-ecological systems as a whole [36,40]. Therefore, a more integrative and holistic approach to sustainable development is needed also in terms of methodological assessment approach, that recognizes the dynamic nature of living systems and focuses on creating health and well-being within those systems. This approach should also address the root causes of insecurity and deeper leverage points within systems, focusing on worldviews and paradigms rather than symptoms [33,41].

Current knowledge in ecology, science, systems theory and related fields, along with the indigenous knowledge and practices, sustain a holistic approach and corresponding actions [42,43]. Consequently, the adoption of a holistic worldview involves the integration of several ways of knowing and perceiving such as ecological, cultural, social, and geophysical components of living (i.e., socio-ecological systems) and their spatial-temporal dynamics [44]. When this integration occurs, the goal of sustainable development shifts from efficiency and mitigating environmental damage to growing the capacities of living systems and continually improving their vitality, health, and abundance, in other words, “thrivability” [45,46,47,48].

3. Existing Methodologies for the Calculation of Environmental Burden and Environmental Repair

In the following, the outcomes of a survey on existing methodologies currently used for calculation of the damage (environmental burden) and the calculation of the environmental repair (offsets) are summarized.

3.1. Environmental Burden

3.1.1. Product-Oriented

Life Cycle Assessment (LCA) is the most known Life Cycle Thinking (LCT)-based methodology to calculate the potential environmental impacts of a product or a service accounting the individual environmental impact categories and across the life cycle phases (ISO 14040-44) [22,23]. According to the standard ISO 14040, the methodology of LCA includes four main phases: Goal and scope definition, Life Cycle Inventory (LCI), Life Cycle Impact Assessment (LCIA), Interpretation.

Other Standards related to LCA are worth mention. For instance, the International Standard ISO 14067:2018 states the principles and the requirements with a particular focus on the guidelines for the quantification and assessment of the carbon footprint related to a product [20], whilst the ISO 14046:2014 specifies the principles, requirements and guidelines related to the assessment of water footprint related to products, processes and organizations based on LCA methodology (ISO 14046:2014 Environmental management—Water footprint—Principles, requirements and guidelines [49]). Formerly developed to be employed as a decision support tool for environmental management, LCA encompasses several related applications such as external communication of life cycle-based environmental information through labels and declarations. In particular, Environmental Product Declaration (EPD) is standardized (ISO 14025 [50]) and produces reliable results on the environmental performance of a product. These findings are obtained from LCA study mainly carried out following a set of rules defined as the Product Category Rules (PCR) which provides rules, requirements, and guidelines for a defined product category [51,52]. Among the rules set by PCRs, the most important are the following: functional unit, system boundaries, data quality, cut-off, and allocation. Therefore, such product-specific rules allow a reliable comparison and communication of LCA results, thus representing a valuable tool for organizations needing to calculate their footprints in a scientific way.

At the European level, a multi-criteria methodology for the calculation of the environmental footprint of goods/services was established and referred as the European Commission’s Product Environmental Footprint (PEF) (EU Commission Recommendation 2021/2279, [53]). Indeed, in 2013, the PEF Guide was published by the European Commission including a commission recommendation on the use of methods and procedures for measuring and subsequent communication of the life cycle environmental performance related to products and organizations [54]. Furthermore, this document provides a guidance on method to calculate PEF and to develop product category-specific methodological requirements for use in Product Environmental Footprint Category Rules, named PEFCR [55].

Life Cycle Costing (LCC) is a well-established methodology for the calculation of the overall cost ascribed to a product or a service over its lifespan or life cycle. Consequently, the LCC is commonly suitable for the economic evaluation of different design alternatives, which meet a required performance level although having different investment costs, operation and maintenance costs, and also varying life spans [56,57]. Despite being employed by both decision-makers and businesses, LCC has not been fully standardized yet. Only sectoral guidelines and methodological guides have been published. For example, the standard ISO 15686-5:2017 [58] provides requirements and guidelines for performing life-cycle cost analyses of buildings and constructed assets. It defines LCC as a systematic economic evaluation of life-cycle costs over a period of analysis. In the literature review performed within the Horizon 2020 REFRESH Project “Methodology for evaluating LCC) [59], three main approaches were identified: the Conventional Life Cycle Costing (C-LCC), the Environmental Life Cycle Costing (E-LCC), and the Societal Life Cycle Costing (S-LCC) [60].

C-LCC methodologies are mainly employed by the public sector and business to make decisions, regarding products and investments that require high initial capital investment (e.g., energy systems, buildings, transport systems, military equipment, and durable goods) [61]. Furthermore, E-LCC mainly focuses on the LCA-related meaning, comprising all stages from feedstock supply, subsequent consumption, and the end of life. Conversely, the C-LCC focuses on products, services, or investments life span, not including the upstream and downstream segments or processes. The Society of Environmental Toxicology and Chemistry (SETAC) published in 2011 a code of conduct for the environmental life-cycle costing, with the aim of providing the main knowledge regarding the application of LCC in parallel with LCA and for stimulating the peer-reviewed research to further improve the methodology, increasing the consensus for an international standard that matches the ISO 14040 standard for LCA [62]. S-LCC has a wide perspective and accounts for all costs covered by society, both nowadays and in the long-term future. Besides costs assessed by C-LCC and E-LCC, it also includes additional social and environmental externalities converted into monetary terms, thus aiming at assessing the overall direct and indirect costs covered by the society [60].

3.1.2. Organization-Oriented

The organization carbon footprint accounts for the GHG emissions from all the activities across the organization, including energy used in industrial processes, buildings, and company vehicles. The two most known international GHG calculating methodology standards are: ISO 14064 and GHG Protocol. ISO 14064 is an international standard for quantifying and reporting greenhouse gas emissions. In particular, its Part 1 guides development of a GHG inventory that can be compared with other inventories of other organizations regardless of sector or national origin. The standard can also assist governmental agencies by providing a foundation for GHG reporting (ISO 14064-1:2018 Greenhouse gases—Part 1: Specification with guidance at the organization level for quantification and reporting of greenhouse gas emissions and removals) [18].

The GHG Protocol, developed by the World Resources Institute (WRI) and the World Business Council for Sustainable Development (WBCSD), defines clear requirements for the structure and content of corporate carbon reports and contains many guidelines related to procedures and methods for GHG calculation. The protocol covers the calculation methodology for Scope 1 and 2, the calculation of direct and indirect energy emissions, respectively. While a separate guide for indirect GHG emissions calculation is reported in the Scope 3 (emissions from the supply chain, The Greenhouse Gas Protocol) [17]. Furthermore, a GHG inventory conducted under ISO 14064 accounts for key aspects consistent with the broadly recognized Greenhouse Gas Protocol. The main difference between the two methodologies is that the GHG Protocol identifies and provides options for GHG inventory best practices, while ISO 14064 establishes minimum standards for compliance with these best practices [63]. At the European level, as happened for products, the European Commission proposed Organization Environmental Footprint (OEF) methods and Organization Environmental Footprint Sector Rules (OEFSRs) as a common way of measuring environmental performance (EU Commission Recommendation 2021/2279, [53]). As with PEF, OEF is the EU recommended Life Cycle Assessment (LCA) based methods to quantify the environmental impacts of organizations.

3.2. Offset

3.2.1. GHG Accounting

Several methodologies and guidelines for GHG accounting exist. Rules are different depending on the market in which the assessment takes place. The global carbon market, designed to provide a market-based approach to address increasing carbon emissions, can be divided into compliance and voluntary markets [64]. The compliance market is also considered the regulated one and it works to help businesses and corporations producing high emissions levels to attain the legal regulatory requirements operating under emission caps. Furthermore, the compliance market is under the framework of the United Nations. Conversely, the voluntary carbon market (VCM) is beyond any legally binding emission reduction and compliance framework [65], it is supported by companies and individuals who take responsibility for offsetting their own emissions [66,67]. Carbon credits exchanged in these to markets are generated through activities or projects that reduce or remove carbon emissions from the atmosphere. There are several types of carbon credits, which can be classified based on the market (compliance and voluntary carbon credits), the type of project that generates them or the standard used to certify them.

Compliance Market and Carbon Credits

The compliance market is used by companies and governments that by law have to account for their GHG emissions. It is regulated by mandatory national, regional, or international carbon reduction regimes/agreements. As the quality of GHG inventories relies on the integrity of the methodologies used, the completeness of reporting and the procedures for compilation of data, the United Nations Framework Convention on Climate Change (UNFCCC) Conference of the Parties (COP) has developed standardized requirements for reporting national inventories covering emissions and removals of GHGs (UNFCCC reporting guidelines on annual inventories for Parties included in Annex I to the Convention [68]).

Among crediting schemes developed under the Kyoto Protocol [69], the Clean Development Mechanism (CDM) was the largest international carbon market project-based crediting mechanism for greenhouse gases [70]. It was established to incentivize the implementation of emission-reductions projects in developing countries through earning certified emission reduction (CER) credits. Baseline and monitoring methodologies are agreed with the UNFCCC Executive Board in order to identify a consistent method for determining the emissions reductions obtained from the project. Furthermore, they are required to establish the emissions baseline of the project (or expected emissions without the project) and to monitor the trend of the emissions once the project is implemented [71].

Other existing or emerging market mechanisms for mitigation of GHG include national/bilateral and (sub)national crediting schemes mechanisms [72]. Since the adoption of the Paris Agreement (PA) [2] and Paris Rulebook for Article 6 implementation at COP26 [73], global efforts to operationalize and utilize PA Article 6 market mechanisms have stepped up. To date, over 250 baseline and monitoring methodologies and 35 related tools approved under the CDM can potentially be aligned with the Paris Rulebook through credible additionality tests and baselines, and monitoring methodologies. The II-AMT is an international expert-led process to enable the alignment of approved Clean Development Mechanism (CDM) baseline and monitoring methodologies with rules and principles for collaboration under Article 6 of the Paris Agreement [74].

However, some regulations have been recently proposed to avoid any risk of “carbon leakage” which occurs when businesses relocate the carbon-intensive production in countries with less stringent climate policies. In this regard, the EU policy tool “Carbon Border Adjustment Mechanism” (CBAM) is aimed at ensuring that the climate objectives of a country are not undermined by the imports from countries with lower environmental standards [75]. Consequently, it will guarantee that the carbon price of imports is equivalent to the carbon price of domestic production.

Voluntary Carbon Market

Several protocols and standards are available in the voluntary carbon credits market [76].

Various standards and protocols guide GHG accounting, providing a structured framework for measuring, reporting, and verifying emissions data, ensuring consistency and credibility in the VCM. Robust GHG accounting follows common principles and is supported by credible and robust standards. Emissions units in the voluntary market, which are commonly called Verified Emission Reductions (VERs), are differentiated according to the registry and verification type. There are several different unit types, with the most widely traded under the Voluntary Carbon Standard (Verra, VCS), the American Carbon Registry (ACR), the Climate Action Registry (CAR), and the Gold Standard (GS) [72,77].

Similar to a CDM or JI project, a VER project must satisfy several requirements such as eligibility and additionality and also accounting for specific baselines and project emissions methodologies. All these standards refer to their own methodologies. Moreover, most of the methodologies approved by the UNFCCC’s CDM are eligible for use within the VCM. Therefore, despite being considered a valuable opportunity to be pursued, the voluntary market is characterized by fragmentation, lack of regulation and monitoring mechanisms, non-uniform certification, verification, and registration procedures [65,78,79].

3.2.2. Water, Biodiversity and Soil Accounting

Non-carbon benefits, also known as co-benefits and sustainable development goals are integrated into carbon standards, (i.e., Gold Standard and Plan Vivo) [80,81], or added to carbon credit projects (i.e., The Climate, Community and Biodiversity (CCB) Standards, and The Sustainable Development Verified Impact Standard (SD VISta)) to also account for social, biodiversity, and other non- carbon sustainability benefits [82,83]. Likewise, GHG accounting and carbon credits, water, and biodiversity credit are financial mechanisms gaining popularity internationally. The relevant examples recently developed at international level are reported in the following sections.

Water Units

Similar to carbon credits, a new idea initiative aiming to help both the global water management system and economy alike is the concept of water credits. In a water credit system, water quality becomes a tradable commodity and water credits are one of the financing mechanisms to drive collective action toward common climate adaptation goals. Examples are the United Nations GEMS/Water Program by which credit concept (Green Water Credits, GWC) incentivizes upstream farmers to invest in green water management practices, prospected to reduce runoff, increase groundwater recharge and reduce harmful sedimentation of reservoirs [84]. Likewise, the U.S. Environmental Protection Agency (EPA) Water Quality Trading Policy foreseen trading of externalities such as phosphorus and nitrogen is performed via permits. Furthermore, the private initiative Water Credit Initiative [85], funded through the organization Water.org, applies principles of microfinance to the water and sanitation sector in developing countries. Water credits represent a fixed quantum of water that is conserved or generated and can be transacted between water deficit and water surplus entities within a sub-basin. Unlike the atmosphere, the spatial limit for transaction should remain within the same hydrological unit, that is a river basin or watershed. The Water Benefit Standard (WBS) is the first globally consistent standard to certify the positive water and socio-economic impacts of projects that supply, purify, and/or conserve water. Water Benefit Certificate (WBC) represents a volume of water that has been sustainably supplied, purified or conserved. Unlike the CERs generated under the CDM, WBCs cannot be used as ‘offsets’ [86]. A specific WBCs methodology on Water Access and Water, Sanitation and Hygiene (WASH) has been developed for this purpose [87]. At the time of writing, only three projects have been registered since 2012 within the Water Benefit Standard Registry [88].

Biodiversity Units

To take urgent action to stop and reverse the loss of biodiversity and to safeguard land and marine areas, innovative financial mechanisms and Biodiversity Financing Plans (BFPs) are foreseen by the Convention on Biological Diversity (CBD) [89]. One example of such an innovative financial mechanism is represented by “biodiversity credit”, an asset generated by investments in the restoration, conservation, and increase in biodiversity and measured through verified progress made in improving the overall well-being of an ecosystem and/or the quantity of target species in the specific area [90]. Biodiversity offsets are “measurable conservation outcomes resulting from actions designed to compensate for significant residual adverse biodiversity impacts arising from project development after appropriate prevention and mitigation measures have been taken” [91]. Consequently, they are based on the concept that impacts generated from development could be offset by protecting and enhancing habitat elsewhere [92]. Furthermore, they allow the continuous development inside an overall objective of no net loss, or net gain of biodiversity. As reported elsewhere, biodiversity offset programs could be organized at local level, at state or provincial level, and at national level (e.g., US Wetland Compensatory Mitigation) [93,94].

Several different methodologies, which could be adopted or adapted as appropriate by countries wishing to introduce biodiversity offset schemes, are available, only a few schemes endorse a particular methodology (e.g., Western Cape, South Africa; Victoria, Australia; New South Wales, Australia) [95]. Therefore, despite existing approaches and methodologies, standardized requirements on measurability, monitoring, verification, and certification remain an issue. So, initiatives such the Biodiversity Credit Alliance (BCA), a partnership facilitated by UNDP and UNEP FI, are growing to bring clarity and guidance for the formulation of a credible and scalable biodiversity credit market under global biodiversity credit principles [96].

A possible market for biodiversity credits is represented by the soil remediation market. Recently, the governments around the world enforced private capital participation in soil remediation and the consecutive productive use of land and its redevelopment. Indeed, the business case is represented by the value obtained in the increase in the retail price of land and the related opportunities of business once the remediation is finalized [97]. Furthermore, the soil remediation based on the principle of “fit for use” represents the baseline on which the feasibility to attract private capital might be effectively evaluated. In this context, the soil remediation markets need the accessibility to information such as land contamination registers/inventories, costs, and characteristics of remediation technologies and, most importantly, forecasts on land value increases and revenues from commercial activities that could be obtained after soil remediation. This increases the engagement of private counterparties that might support the costs and risks of soil remediation on the condition that they can develop the site for residential, industrial, or commercial use. However, the engagement of private capital on soil remediation is limited since the current financial strategies of the government are not effective in attracting private financial investments. For instance, the International Institute for Sustainable Development (IISD) recently explores the innovative approaches to financing the cleanup and remediation of contaminated soils blending public and private capital providing preliminary insight on innovative approaches [97].

With a new international framework combined with the global trend of making Environmental, Social, and Governance (ESG) standards mandatory for businesses, global investments in biodiversity are expected to grow rapidly, particularly in the private sector.

4. Design of Methodology

The proposed methodology is based on the following three pillars:

• Reduce: before starting their climate contribution strategy, organizations shall demonstrate to have at least a Net Zero Pledge and Plans;
• Remove: regenerative units are issued only by projects removing CO₂ from the atmosphere and, at the same time, contributing to water and biodiversity/soil benefits;
• Repair: regenerative projects shall be designed to restore and repair parts of the damaged climate systems.

In the following, after describing key features for effective methodology design, the methodology is described using a step-by-step approach.

4.1. Key Features

The performed survey on existing methodologies for damage and offsets calculations highlights a number of key features related to the design and implementation phases of a project that have been carefully considered for effective methodology design. Key issues that have been identified are:

• Environmental burden: footprint calculations (i.e., carbon, water, and ecological);
• Environmental repair: climate contributions;
• Regenerative projects: eligibility, additionality, timing and permanence, monitoring, reporting and verification;
• Equivalence balancing ratios: Regenerative Contribution Units (RCUs).

An in-depth description of each one is reported in the next sections.

4.1.1. Environmental Burden

The basis for environmental burden assessment was the literature on LCA methodology covering the available standards (e.g., ISO 14040-44 [22,23]), guidelines (e.g., European Commission, Joint Research Centre [98]), and scientific peer-reviewed publications on LCA methodology. The first step is the calculation of the environmental burden. An LCA was performed according to standard ISO 14040 and was chosen as a methodological pattern to quantify the environmental impacts of products (goods or services). In EU context, the PEF Guide could be used as a reference. If available, Product Category Rules (PCRs) or Product Environmental Footprint Category Rules (PEFCRs) shall be used as specific rules. In order to avoid burden shifting, not just carbon footprint, but also ecological footprint and water footprint shall be accounted for. At the organizational level, a GHG inventory according to GHG Standard or ISO 14064-part 1 shall be performed. Other burdens should be calculated according to the Environmental Footprint (EF) method and to specific Environmental Footprint Sector Rules (EFSR). The methodology includes the following indicators: carbon footprint, water footprint, and ecological footprint. Specifically, the Carbon Footprint Profile (according to standard ISO 14067:2018 [20]) is determined based on the indicator Global Warming Potential (GWP) total [ton CO₂ eq.], which considers the contributions from Fossil, Biogenic, Land Use and Land-Use Changes (LULUC) and water deprivation potential (WDP) [m³ eq.] [99]. The impact on ecosystem quality from land transformation and occupation is empirically characterized at the biome level (e.g., ecological footprint) is quantified through the following impact categories: land transformation, biodiversity [m² yr arable], and land occupation, biodiversity [m² yr arable] (method IMPACT World+) [100].

4.1.2. Environmental Repair

To go beyond offsetting, a market approach based on credits by projects reducing emissions, even if additional, is not enough. Regenerative projects shall enhance carbon uptake, thus removing carbon dioxide from the atmosphere. Also net zero target, defined “when anthropogenic emissions of greenhouse gases to the atmosphere are balanced by anthropogenic removals over a specified period” [4], is no longer adequate to avoid large-scale effects (Sixth Assessment Report, IPCCC-AR6). The report, titled ‘The Final Warning Bell’ suggests that even if countries achieve net zero by mid-century, this will not tackle greenhouse gases already in the atmosphere, with CO₂ equivalent concentrations potentially continuing to climb as high as 540 ppm (parts per million). Then net negative (or climate positive) rather than net zero strategies are required. Climate positive is defined as “When an actor’s greenhouse gas removals, internal and external, exceed its emissions and any removals are “like for like”. Must be specified over a declared time period and whether removals and emissions are cumulative or represent only the time period specified” [101]. So, climate contribution projects should be positive and the balance between footprints and regenerative units needs to be moved towards the latter, leading to a higher number of units compared with the impacts. Finally, climate contributions should be achieved only through the support of carbon removal projects, which, at the same time, enhance biodiversity, restore soil, and increase the availability of clean and safe water, thus quantitatively contributing to SDGs 6, 13, 14, and 15.

4.1.3. Regenerative Projects

The regenerative projects (RPs) should be relevant and eligible under the SDG bond criteria, particularly in relation to the goals listed below.

SDG 6 “Clean Water and Sanitation”: ensure availability and sustainable management of water and sanitation for all;

SDG 13 “Climate Action”: take urgent action to combat climate change and its impacts;

SDG 14 “Life below water”: conserve and sustainably use the oceans, seas and marine resources for sustainable development;

SDG 15 “Life on Land”: protect, restore and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss.

To be considered regenerative, eligible projects should demonstrate their additionality and permanence during time. Benefits should be additional compared with their baseline scenario (i.e., the benefits of the project are beyond a business-as-usual scenario), meaning that their contribution in terms of carbon removal and sustainable development are beyond those that would have occurred in the absence of the regenerative project. In particular, a regenerative project should deliver conservation gains over and above what is already taking place or planned. Additionality of regeneration of biodiversity, land, and water can be assessed by demonstrating that the proposed management interventions could be feasible in enhancing the biodiversity given the larger economic and demographic trends, the landscape framework (e.g., ecosystem connectivity) and the current level of protection of the proposed area. Several instruments can be used to perform this process, including biodiversity maps, spatial plans, and National Biodiversity Strategies and Action Plans [102].

Additionality should be demonstrated for each contribution and goal, following guides and tools such as the CDM “Methodological Tool—Demonstration of additionality of small-scale project activities” [103].

Regarding permanence, to be considered removed, CO₂ must be captured from the atmosphere, stabilized, and stored durably. Moreover, the permanence is also the assumption that the biodiversity offsets should exist at least as long as the negative impacts from development persist and ideally in perpetuity. Offset regulations for native vegetation in NSW Australia, for instance, call for offset benefits to “persist for at least the duration of the negative impact of the proposed clearing” [104] and US Conservation Banking policy requires banks to “safeguard in perpetuity the species or habitat conservation values upon which the credits are based” [105].

RPs might be also deemed in view of Program of Activities (PoA), intended as the project development under the UNFCCC Clean Development Mechanism (CDM) [106]. Specifically, PoA is a voluntary coordinated action by a private or public entity aimed at implementing and promoting any incentive schemes and/or voluntary programs which contribute to GHG emission reduction or to increase the net GHG removals by sinks. Furthermore, PoA are mainly managed on a regional level speeding up the approval process and, after its registration, a PoA might account for several CDM Program Activities (CPAs). However, compared with UNFCCC PoA, that are restricted to GHG and contribution to climate neutrality, the RPs PoA would account for other environmental contributors in order to enhance biodiversity, restore soil and increase the availability of clean and safe water. In the framework of RPs, PoA would make it more feasible to gain positive contributions for each considered goal. In the following the main criteria for eligibility and additionality assessment are summarized and categorized according to SDGs and related targets.

Climate Units

Eligible projects should be those coherent to SDG 13 [107], i.e., projects removing carbon dioxide from the atmosphere. Projects related to industrial Carbon Capture and Storage (CCS) associated with geoengineering or energy generated from fossil fuel or nuclear fossil fuel switch should not be eligible under the methodological pattern.

Types of projects are:

• Biochar;
• Carbonated Materials;
• Geologically Stored Carbon;
• Direct Air Capture;
• Enhanced Rock Weathering;
• Terrestrial Storage of Biomass;
• Carbon Farming projects.

Units are based on tons of CO₂ equivalents of removed carbon. Costs of removal are taken into account in the definition of the reference unit. Balance between carbon footprint and carbon units are based on ton CO₂ equivalent.

Ecological Units

Eligible projects should be those coherent to SDG 15 [108], i.e., projects increasing biodiversity and regenerating soil.

Types of projects are:

• Terrestrial ecosystem restoration (e.g., biodiversity enhancement);
• Restore degraded forests;
• Brownfields regeneration (e.g., regeneration of brownfield land to green infrastructure; redevelopment of contaminated brownfield land [109]);
• Soil remediation.

Units are based on m² equivalents of regenerated soil. Costs of regeneration are taken into account in the definition of the reference unit. Balance between ecological footprint and ecological units are based on m² equivalent.

Water Units

Eligible projects should be those coherent to SDG 6 [110], e.g., projects expanding public access to safe and affordable drinking water, improving water quality, wastewater treatment, and to SDG 14 [111], e.g., projects aim at protecting and restoring water related ecosystems and coastal and marine areas.

Types of projects are:

• Improving water quality;
• Wastewater treatment (e.g., improve water reuse);
• Restoring water-related ecosystems (including oceans, seas, wetlands, rivers, aquifers, and lakes);
• Restoring coastal and marine areas (e.g., lagoon valley);
• Aquatic ecosystem restoration (e.g., seagrass, mangroves, Posidonia bed).

Units are based on m³ equivalents of regenerated water. Costs of regeneration are taken into account in the definition of the reference unit. Balance between water footprint and water units are based on m³ equivalent.

A summary of selected Targets and Indicators related to SDGs 6, 13, 14, and 15 are reported in

Table 1. Summary of selected Targets and Indicators related to SDGs 6, 13, 14, and 15 [107,108,110,111].

Targets	Indicators
SDG 6 “Clean Water and Sanitation” [110]
6.1 By 2030, achieve universal and equitable access to safe and affordable drinking water for all.	6.1.1 Population using safely managed drinking water services.
6.3 By 2030, improve water quality by reducing pollution, eliminating dumping and minimizing release of hazardous chemicals and materials, halving the proportion of untreated wastewater and substantially increasing recycling and safe reuse globally.	6.3.1 Domestic and industrial wastewater flows safely treated; 6.3.2 Number of bodies of water with good ambient water quality.
6.6 By 2020, protect and restore water-related ecosystems, including mountains, forests, wetlands, rivers, aquifers and lakes.	6.6.1 Changes in the number of water-related ecosystems over time.
SDG 13 “Climate Action” [107]
13.2 Integrate climate change measures into national policies, strategies, and planning.	13.2.2 Total GHGs emissions per year.
13.3 Improve education, awareness-raising and human and institutional capacity on climate change mitigation, adaptation, impact reduction and early warning.	13.3.1 Extent to which (i) global citizenship education and (ii) education for sustainable development are mainstreamed in (a) national education policies; (b) curricula; (c) teacher education; and (d) student assessment.
SDG 14 “Life below water” [111]
14.1 By 2025, prevent and significantly reduce marine pollution of all kinds, from land-based activities, including marine debris and nutrient pollution.	14.1.1 (a) Index of coastal eutrophication; and (b) plastic debris density.
14.2 By 2020, sustainably manage and protect marine and coastal ecosystems to avoid significant adverse impacts, including by strengthening their resilience, and act for their restoration in order to achieve healthy and productive oceans.	14.2.1 Number of countries using ecosystem-based approaches to managing marine areas.
14.5 By 2020, conserve at least 10% of coastal and marine areas, in accordance with national and international law and based on the best available scientific information.	14.5.1 Coverage of protected areas in relation to marine areas.
SDG 15 “Life on Land” [108]
15.1 By 2020, guarantee the conservation, restoration and sustainable use of terrestrial and inland freshwater ecosystems and their services (particularly forests, wetlands, mountains, and drylands).	15.1.1 Forest area as a proportion of total land area. 15.1.2 Proportion of important sites for terrestrial and freshwater biodiversity that are covered by protected areas, by ecosystem type.
15.2 By 2020, encourage the implementation of sustainable management of all types of forests (e.g., through halt deforestation, restore degraded forests and substantially increase afforestation and reforestation).	15.2.1 Progress towards sustainable forest management.
15.3 By 2030, combat desertification, restore degraded land and soil, including land affected by desertification, drought and floods, and endeavor to achieve a land degradation-neutral world.	15.3.1 Proportion of land degraded over total land area.
15.4 By 2030, ensure the conservation of mountain ecosystems, including their biodiversity, to enhance their capacity to provide benefits that are essential for sustainable development.	15.4.1 Coverage by protected zones of important sites for mountain biodiversity.
15.5 Take urgent and significant actions for reducing the degradation of natural habitats, halt the loss of biodiversity. By 2020, protect and prevent the extinction of threatened species.	15.5.1 Red List Index.
15.8 By 2020, introduce measures to prevent the introduction and significantly reduce the impact of invasive alien species on land and water ecosystems and control or eradicate the priority species.	15.8.1 Proportion of countries adopting relevant national legislation and adequately resourcing the prevention or control of invasive alien species.

.

4.1.4. Equivalence Balancing Ratios

As a general assumption, considering that two areas are not ecologically identical, identifying the contributions needs the assessment of how to reach benefits at repaired sites that are equivalent to the losses at the specific area. This is actual for biodiversity and water, while climate change is judged as a global impact category and its impacts do not depend by the place where the emissions occur [112].

For the purpose of this methodology, as there is a supply shortage of like-for-like repaired sites, an out-of-kind approach, allowing for different forms of restoration to those affected by development, is chosen [113,114].

A simple metric is chosen ton for carbon removal, m² for soil/biodiversity and m³ for water. Then, a balancing replacement ratio (multiplier) can be assigned. This indicates how many units should be generated at the repaired site per unit lost at the impact site. Moreover, ratios may depend on the proposed regenerative actions (e.g., preservation versus restoration), differences among expected losses and gains in the ecosystem functions, spatial and temporal losses, and other risks and uncertainties. Furthermore, the metrics and multipliers developed in the framework of biodiversity offsets could be considered in the definition of the methodology [90].

For restoration projects (e.g., soil remediation), a cost-of-restoration approach might be chosen. This involves the estimation of the costs that would be required to restore the site to a comparable state or condition (in relation to the lost one). The cost-of-restoration shall balance the LCC costs (as described in Section 3.1.1.).

RCUs are generated by regenerative projects which simultaneously contribute to climate, biodiversity, and water units. Each RCU (RCUclimate, RCUwater, RCUecolog) represents a regenerative unit covering the three single units with ratio 1:1.

To define the climate contribution as regenerative, the balance shall be positive, hence the amount of RCUs shall exceed the calculated three footprints. For traceability, transparency and to avoid double counting, RCU shall be registered on public registries, preferably managed by Designated National Authorities.

In the transitory phase, unless regenerative projects are developed, a project claiming to be “regenerative” can contribute separately to each burden balancing climate, biodiversity and water units by choosing projects contributing to one, without undermining any of the other two environmental goals. An approach coherent to the European DNSH principle (Do No Significant Harm) and the International “No-Harm Rule” can be followed [115].

4.2. Main Steps of the Proposed Methodology

The proposed methodology, based on the above considerations, encompasses the following steps:

• At product level: realization of LCA study and quantification of carbon footprint, water footprint and ecological footprint;
• At organizational level: realization of GHG inventory, together with water and ecological assessment;
• Choose or develop RPs in accordance with SDGs;
• Realize climate contribution, ensuring a positive balance between the three environmental footprints and RCUs.

The proposed methodology might be displayed through the decision-making tree reported in Figure 1.

5. Calculation and Balancing Example

In order to preliminary explore the feasibility of the proposed methodology, an attempt of balancing between environmental burden calculated through LCA and RCUs has been conducted and the main findings are reported in the following sections.

5.1. Calculation of Environmental Burden through LCA

As discussed above and as also reported in Figure 1, the proposed methodology encompasses the calculation of environmental burden through LCA as a 1st step.

Specifically, the operations of a tourist accommodation facility (comfort category 3*) has been considered as the source of impacts. Specifically, according to the database Ecoinvent 3 (Building operation, budget hotel {BR}|building operation, budget hotel| Cut-off, U), it is assumed that the hotel is located in Brazil, covering a total area of ~827 m² and it has an average annual occupancy equal to 20,440 guest nights per year. LCA study has been conducted using the commercial software SimaPro 9.5.

Some environmental impact categories have been selected to quantify the carbon, water, and ecological footprints.

Table 2. Results of LCA study conducted to quantify the environmental impacts related to the operations of a tourist accommodation facility.

Environmental Impact Category and Method	U.M.	Value (1 Guest Night)	Value (Average Annual Occupancy = 20,440 Guest Nights per Year)
Global warming potential (GWP100)	[tonCO2eq]	10.04 × 10−3	205.25
Water Deprivation Potential (WDP)	[m3 eq]	2.1	42.9 × 103
Land Use, transformation	[m2 arable year]	2.23 × 10−3	45.6
Land Use, occupation	[m2 arable year]	0.86	17.5 × 103
Land occupation	[m2 year]	2.11	43.1 × 103
Extinction of species	[NEX]	1.26 × 10−15	2.6 × 10−11

reports the environmental impact categories, related methods, and the main findings obtained in terms of both 1 guest night (i.e., functional unit of LCA) and the average annual occupancy of the hotel (20,440 guest nights per year).

5.2. Identify the Potential Regenerative Projects (RPs)

In view of the holistic approach proposed based on the RCUs, one or more regenerative projects might be properly designed and implemented to balance the carbon, water, and ecological footprint of the hotel operations previously calculated.

To achieve this goal, a search in the Gold Standard registry [116] has been conducted in order to identify potential regenerative projects. Specifically, the relevant information and data on environmental and social benefits have been collected by reviewing the available documentation.

Among the available projects in the Gold Standard Registry [116], the afforestation project entitled “Chestnut Sustainable Restoration Project” might be selected as referred regenerative project after assessing its additionality and eligibility under the selected SDGs (e.g., 6, 13, 14, and 15). The main purpose of the project is to increase the carbon stocks and retain GHG; however, it also contributes to meet some SDGs such as 3—Good Health and Well-Being, 6—Clean Water and Sanitation, 8—Decent Work and Economic Growth, 11—Sustainable Cities and Communities, 13—Climate Action, 15—Life on Land, and 17—Partnership for the Goals.

Consequently, the project might be a potential candidate as RP and the RCUs might balance the impacts related to the hotel facility.

The information has been collected from the validation report available online [117] and those relevant to attain the balance with the environmental impacts previously calculated for the hotel are reported in

Table 3. Summary of the main estimated contribution to SDGs of the “Chestnut Sustainable Restoration Project”.

Estimated Contribution	U.M.	Value
Net GHG Emission Reductions and Removals	[VERs/year]	28,356.85
Number of acres certified under FSC	[acres added per year]	8888
Number of new acres planted	[acres planted per year]	3900
Water quality	[average TMDL compliance per year]	93%
Number of seedlings planted	[seedlings planted per year]	1,926,600

TMDL: Total maximum daily load; FSC: Forest Stewardship Council.

for comparison purposes.

Comparing Table 2 and Table 3, it can be assessed the feasibility of the selected project to balance the environmental impacts related to the operations of the tourist accommodation facility previously presented. As it can be noted the balance between RCUclimate (expressed as Net GHG Emission Reductions and Removals) and Carbon footprint (expressed in terms of Global warming potential, GWP₁₀₀) might be feasible since the related values are expressed in terms of equivalent units of measure.

Conversely, the benefits of the regenerative project to the water issue (RCUwater) were reported in terms of water quality and expressed in the percentage of average TMDL compliance per year. As a consequence, the potential balancing between RCUwater and Water footprint (expressed as Water Deprivation Potential, WDP) is not feasible at the current form and not easily achieved. The development of a similar unit of measure (e.g., m³eq) for expressing both the RCUwater and Water footprint is strongly advised and developed at international scale. This point should be a priority for both LCA practitioners and project manager involved in the design of regenerative projects. Furthermore, a more measurable unit for RCUwater will allow to readily understand the beneficial effect of a specific project making also more effectiveness the selection of a specific regenerative project instead of another one. Similarly to RCUwater and Water footprint, the balance between Ecological Footprint and RCUecolog needs further investigations. Firstly, it was found that the projects available on public registries (e.g., Gold Standard Registry [116]) lack several information related to biodiversity regenerative contribution. When available, the beneficial contribution is often reported qualitatively through a scoring system.

Further efforts should be devoted to properly quantify the beneficial contributions of a project in terms of biodiversity conservation and soil preservation accounting also the overall well-being of an ecosystem and/or the quantity of target species in the predefined territory. To reach this goal, a comprehensive unit of measure should be universally employed. Moreover, the unit of measure for RCUecolog should be similar to the that currently used for the calculation of Ecological footprint through LCA.

As deeply elucidated, the assessment of RCUs requires a broader and integrated approach, consequently both emissions and positive climate impacts of actions/projects need to be quantified through a similar metrics. Further investigations should be conducted to fill the current gaps on regenerative projects making more accessible and available the information related to their nature contributions.

6. Conclusions and Final Remarks

The aim of this paper was to develop a methodological LCA-based approach for the definition of Regenerative Contribution Units (RCUs) to quantitatively assess the contribution of projects in line with SDGs and the framework of regenerative model development. In this context, the study proposes a first step in identifying new evaluation methodology for interventions aimed at implementing the SDGs.

The holistic approach proposed by the RCUs could help to overcome the limitations of traditional sustainability assessment, allowing for a more comprehensive and integrated assessment of the impacts and benefits. Consequently, the evaluation is not only devoted to the environmental impacts but also to the health of social-ecological systems and the evaluation of their capacity to thrive in the long term.

The proposed approach supports the development of more informed decision-making initiatives focused on SDG implementation through a more effective and better contextualized based on the scientific-based Regenerative Development evidence.

The new proposed approach also contributes to overcoming the calculation of carbon offsetting promoting the shift from calculating carbon offsetting to assessing the climate contribution. Indeed, while carbon offsetting calculations primarily focus on neutralizing carbon emissions through offset actions, climate contribution calculations go beyond and also consider the positive climate impacts generated by actions and projects. To calculate climate contribution, it is necessary to assess not only the GHG emissions associated with an activity or project but also the positive impacts it can generate.

The shift to calculating climate contribution requires a broader and integrated approach that evaluates both emissions and positive climate impacts related to actions or projects. This approach allows for the identification and promotion of actions that not only offset emissions but actively contribute to climate change mitigation and adaptation to its effects.

Despite this promising holistic approach, some limitations should be overcome by numerically quantifying the RCUs. It is noteworthy that the values and consequently the units of measure related to water footprint and ecological footprint, as commonly calculated by LCA practitioners, are not consistent with those related to the beneficial contributions evaluated in the existing projects currently available on public registries. Furthermore, when available, the information related to SDGs contribution are often qualitative and/or attributed through a scoring system.

Consequently, the future regenerative projects shall be designed in order to properly quantify the contributions with units of measure that are compliant with those related to impacts.

Another suggested improvement is the accounting for geographical proximity between the source of impacts and regenerative projects, ensuring a more effective positive balance between the three environmental footprints and RCUs. Anyway, the proposed approach could contribute to increase awareness and understanding of the importance of considering not only emissions but also the positive climate impacts of actions and projects, thus leading to an evolution in climate contribution calculations, with greater attention being paid to the integration of multidimensional approaches to effectively address climate change.

The holistic framework of the proposed methodology allows the rating of all dimensions of impacts, and in light of the regenerative development, it might feature on policymakers and future research in the field.

Undoubtedly, after the fine-tuning and further implementation, the proposed methodology will contribute to enhancing the investments in Regenerative Contribution Units making them more profitable. The novel methodology might be attractive for both the private and public sectors by contributing to attaining SDG targets and even more sustainable development. For instance, the private sector might purchase the RCUs to fulfill their corporate ESG obligations. Meanwhile, the public sector might benefit from the scientific understanding of RCUs to support the strategic decision-making process in enhancing project effectiveness and maximizing the positive environmental, social, and economic outcomes for ecosystems and communities.