Water-Energy-Food nexus index proposal as a sustainability criterion on dairy farms.

Cow milk is a fundamental nutrients source for the human diet at all stages of life. However, the decline in cow milk consumption over the years has been driven by increased consumer awareness of animal welfare and the environmental burdens associated. In this regard, different initiatives have emerged to mitigate the impacts of livestock farming, but many of them without addressing the multi-perspective view of environmental sustainability. Thus, the Water-Energy-Food (WEF) nexus emerges as a framework to consider the complex synergies among carbon emissions, water demand, energy requirements and food production. In this study, a novel and harmonised WEF nexus approach has been proposed and applied to evaluate a set of 100 dairy farms. For that, the assessment, normalisation, and weighting of three lifecycle indicators such as carbon, water and energy footprints, as well as the milk yield were carried out to obtain a single value, the WEF nexus index (WEFni), which varies from 0 to 100. Results show that the WEF nexus scores obtained vary from 31 to 90, demonstrating large differences among the farms assessed. A cluster ranking was performed to identify those farms with the worst WEF nexus indexes. For this group, consisting of 8 farms with an average WEFni of 39, three improvement actions focused on the feeding, digestive process and wellbeing of the cows were applied to determine the potential reduction in the two main hotspots identified: cow feeding and milk production level. The proposed methodology can establish a roadmap for promoting a more environmentally sustainable food industry, although further studies are still required in the pathway of a standardised WEFni.

The joint use of life cycle assessment and data envelopment analysis methodologies for eco-efficiency assessment: A critical review, taxonomy and future research.

Eco-efficiency has become a cornerstone for any company that seeks to improve their environmental and economic aspects. In this context, the joint use of Life Cycle Assessment and Data Envelopment Analysis, known as LCA + DEA methodology, is an emerging and growing line of research. LCA estimates the environmental impacts of the products or services, while DEA evaluates their efficiency, providing targets and benchmarks for the inefficient ones. In this way, both the environmental and economic aspects are considered in the eco-efficiency assessment. Since LCA + DEA methodology is a novel research line, a literature review is necessary to depict its full scope and to support researchers and practitioners. This manuscript presents the first comprehensive and structured literature review of the joint use of LCA and DEA for eco-efficiency assessment. We propose a taxonomy for the reviewed articles based on the theoretical and practical issues of LCA + DEA methodology and classify them accordingly. This classification allows recognizing and discussing the main findings, which offer some managerial implications for professionals who want to start employing this methodology. In addition, a procedure for selecting a suitable method is proposed and the main limitations and research opportunities are identified. Finally, this review could be a starting point and a guide for systematically building knowledge about the in the joint use of LCA and DEA for eco-efficiency assessment.

Comparing two CF+DEA methods for assessing eco-efficiency from theoretical and practical points of view.

Nowadays, sustainability has become of increasing concern in policy and the decision making of stakeholders. Companies have been increasing their attention to their environmental performance. In order to measure sustainability performance, different approaches have been proposed. The joint application of Life Cycle Assessment (LCA) and Data Envelopment Analysis (DEA), called LCA+DEA, is used to assess eco-efficiency, which is to produce more with less environmental impact and with fewer resources. In this manuscript, we compare two methods that implement the LCA+DEA approach, the five-step and four-step methods, focused on Carbon Footprint (CF), called CF+DEA. These methods have not been compared previously. This comparison will encompass the theoretical and practical points of view according to efficiency indices, best practices, and targets for the CF emissions. To perform this comparison, we use a case study of raspberry producers in Chile. From a practical point of view, we have observed that both methods have achieved the main objective of reducing CF. Moreover, results show similar eco-efficiency scores; the targets given by the five-step method are less demanding than those given by the four-step method. In this sense, the four-step method provides a higher average CF reduction. This is due to the inclusion of CF as an undesirable output in the DEA assessment and the use of an output-oriented DEA model. Additionally, in including the CF within the DEA assessment, the four-step method reflects better the definition of eco-efficiency. Following these results, it is advisable to implement the targets provided by the five-step method for a short term and then the targets provided by the four-step method for a mid-term or long term.