As of 2016, governments globally adopted the task to achieve social, economic and environmental sustainability by committing to the targets from the UN Sustainable Development Goals (SDGs). The SDGs incorporate a set of 17 goals and 169 targets accompanied with more than 200 indi
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As of 2016, governments globally adopted the task to achieve social, economic and environmental sustainability by committing to the targets from the UN Sustainable Development Goals (SDGs). The SDGs incorporate a set of 17 goals and 169 targets accompanied with more than 200 indicators that can guide towards achieving sustainable development by 2030. Sustainable development and human wellbeing fundamentally rest on the capacity of the biosphere to sustain us. In other words, the economy or society related SDGs can only be reached if the biosphere related SDGs, in which they are embedded, are respected. To ensure the achievement of all SDGs, the environmental impact as a result of human activity needs to be reduced to safe levels. Doing so requires quantification of both impacts and safe operating spaces in the environmental domain. However, from the SDG framework it does not become clear what safe operating spaces are because for many of the environmental issues addressed, quantitative targets based on ecological boundaries are lacking. Life-Cycle Assessment (LCA) is a method that enables holistic analysis of the environmental impact of product-systems by analyzing the impacts over the complete life cycle. Yet, as a comparative method it can only identify the most sustainable product system relative other alternative product-systems. In contrast, there have been developments to develop Absolute Life Cycle Assessment (ALCA), in which the environmental impact of a product-system is compared against a benchmark based on the earth’s ecological carrying capacity, in order to define if the system is absolutely sustainable. Such a benchmark is obtained by allocating a share of the environmental carrying capacity to the product system, using a specific allocation principle. The most recognized expression of environmental carrying capacity has been provided by the planetary boundary (PB) framework, offering a set of quantitative biophysical limits for nine critical earth system processes (ESP). The functioning of these ESPs is critical to keep the earth in its stable Holocene state, which is required for anthropogenic prosperity. Using the LCA method to quantify impacts, and the PB framework to provide quantitative ecological boundaries, ALCA could be useful to identify absolutely sustainable product-systems and support contributions from product-systems towards environmental SDG targets. Yet, an overview showing the availability of different ALCA methods and their applicability at the product level is lacking. Therefore, this master thesis provides a systematic literature review of ALCA methods and applications, that use the planetary boundary (PB) framework as an implementation of carrying capacity. The main research question is formulated as: To what extent is absolute life cycle assessment possible and does it enable a comparison of environmental impact against product-level benchmarks based on the PB-framework, to support the identification of absolute sustainable products contributing to the UN SDGs? With a database search on Web of Science (WoS) and a snowballing approach, possibly relevant publications were identified. Afterwards, 14 key publications were selected that entail either an ALCA method or application. The review was conducted with criteria primarily based on an absolute environmental sustainability assessment (AESA) framework identified from literature. The criteria cover aspects related to LCA, the PB framework and allocation approaches needed to obtain benchmarks at the product-level. The results showed that there are 5 dominant methods, and 9 applications of these methods. Only one of these methods includes a direct comparison of impact against a benchmark specifically allocated to the assessed product-system. Therefore, we concluded that only one method can truly be considered as an ALCA method that is also potentially usable in the context of SDGs. However, even claims of absolute sustainability that are made using this method are not fully conceptually consistent because a comparison is made between an annual benchmark (derived from the PB framework) and LCA impacts that are in reality exerted over many years. Other methods were considered usable for different purposes. Some methods only facilitate a comparison of impact against a per-capita benchmark, representing the occupation of an individual’s environmental budget by the product-system. These methods are rather usable for identifying sustainable consumption patterns. Some methods only enable the determination of impact reduction targets against which future impact reductions might be compared. Others do not involve any form of absolute sustainability comparison and are rather usable in conventional comparative LCA. We provided a terminology proposition for PB related concepts because there seemed to be inconsistencies across publications regarding the use of PB-related concepts and their terminology. Also, there were inconsistencies in the terminology for different allocation principles. We stated that all allocation principles could be classified in three main categories. Yet, further research is recommended to find common ground on the choice for specific allocation principles to obtain benchmarks for product-systems. Also, we recommend further research to focus on getting insights in linkages between LCA impact categories, PB’s and SDGs and combining these insights with the knowledge on ALCA methods that has been provided in this thesis. Such a combination would be the next step to find the potential of ALCA methods for supporting contributions from product-systems towards environmental SDG(-target)s.