Nexus Interviews

Nexus Interview // Dr. Mario Giampietro of the Autonomous University of Barcelona

In this interview, the Nexus Resource Platform speaks with Dr. Giampietro of the Autonomous University of Barcelona about his research on the resource Nexus, the associated challenges, and future plans.

Mario Giampietro is an ICREA Research Professor at the Institute of Environmental Science and Technology (ICTA) and coordinator of the EU-funded project MAGIC.  With an academic background in biology, chemistry and social sciences, he has (co-)authored over 100 articles and is the leading Professor of the course “Sustainability of Social-Ecological Systems: The Nexus between Water, Energy and Food” offered through the Coursera platform.  He has written various books on sustainability, energy analysis, and agriculture, including “The Biofuel Delusion” and “Resource Accounting for Sustainability Assessment”, in which he develops the MuSIASEM approach for the nexus between water, energy, food and land use.


What is NEXUS, and what is its relevance?

The Nexus represents a major challenge to the scientific activity of providing advice to policy because it is incompatible with the dominant paradigm of reductionism. This paradigm provides sophisticated models about energy, food, land or water, but by considering only one resource at a time.  Given that the entanglement among resource flows takes place across different levels of organizations and different scales, it is impossible to represent it using conventional science and models. Because past scientific advice has been based on models addressing one thing at a time, we now have governance doing the same. Hence, you have two main problems inherent in the Nexus: i) representation and ii) governance.

In short, the Nexus challenges the silo structure in the governance structure and the adoption of reductionism in the representation of sustainability issues, both of which currently focus on only one issue at a time.

I am currently coordinating an EU project named MAGIC (Moving to Adaptive Governance in Complexity: Informing Nexus Security) that shows how different policies address different issues, but often not in a coherent way and sometimes even interfering with each other. MAGIC uses the Nexus to show that there are external limits to economic growth. We call this “uncomfortable knowledge”. Today, it is generally believed that we can use business models to decouple economic growth from the consumption of resources.  However, if you are serious about the Nexus, you need to consider all the constraints at the same time, and then you can see that technical quick fixes simply do not exist. This is the third key aspect of Nexus: the uncomfortable knowledge it creates. You cannot solve a problem by making another one worse. There is no silver bullet.  Limits do exist. Seeking effective solutions requires us to consider simultaneously the multiple aspects of the problem, and the Nexus embodies this approach.

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How can Nexus be applied in Public Policy?

Nexus implies potential institutional conflict between environment, water, agriculture, energy and other areas of governance, which makes for difficult policy implementation.  In sustainability, the bottom-line is the need of prioritizing among the diverse concerns in policymaking. Different institutions that make policy have different sensibilities about the nexus.  Each institution is more concerned with its own issue, rather than looking at the whole. There are not many success stories yet, but nonetheless, the nexus remains essential for discussing transboundary and other ‘wicked’ sustainability problems that bring together different stakeholders, forcing them to look together at the different aspects of the problem across multiple scales. This calls for an approach that embraces governance-based negotiation, participatory deliberation, and multisector collaboration, rather than a strictly top-down technocratic approach based on the arbitrary selection of pieces of scientific evidence.

The Nexus invariably brings together different social actors that are clearly identifiable carriers of different perspectives and legitimate points of view. This challenges conventional policymaking relying on experts working on models from behind their desks.

In terms of implementation, the Nexus is creating a crisis in conventional governance, but it also opens up new possibilities for other forms of governance that are more participative, bottom-up, and deliberative. Nexus requires the use of several epistemic boxes: several decision spaces in which to make the required analysis, representing different ways of framing concerns.

Farmers have social agreements on how to handle issues, the same is true for social actors in the energy and the water sector. However, if you get these three points of view together, the existing agreements within the vertical silos must be changed.  It is not only an issue of representation; it is also a matter of trust, of deciding how to share the problem. This makes the governance much more difficult. Society is slowly starting to re-evaluate complexification of sustainability issues, after over a century of reductionism, simplification and specialization (e.g., cost-benefit analysis). If we keep pretending that we can handle complex problems with complicated but simplistic models, we risk losing legitimacy. The Nexus is not limited to water-energy-food, but may also include land use, soil erosion, ecosystem, human activity (time), and other issues.

What is your role in the Institute of Environmental Science and Technology (ICTA) of the Universitat Autònoma de Barcelona (UAB)? How long have you been working in Nexus? How was this program developed, and how successful has it been?  

My research group is working on quantitative story-telling, mostly through the MAGIC project, in which we focus on the plausibility of current stories about sustainability, bringing it down to numbers based on real-world data. The idea is to develop a richer analysis of a particular situation, thereby possibly challenging the “official storytelling”. We do not provide “solutions” telling society what to do, but rather we try to improve the choice of narratives and the understanding of sustainability issues.

There is an urgent need for double-checking what is being proposed by policymakers both in terms of explanations of the crisis and the proposed solutions. You can easily see this if you look at the current political crises worldwide.  People no longer believe the promises of governments for solving problems. Energy use keeps growing despite policies endorsing renewable energies and energy efficiency, and recycling rates have only marginally improved despite the popularity of the circular economy narrative. We are simply compromising the credibility of the system if we keep doing “more of the same”. A Nexus approach may change this as it can show that many of the claims of politicians are not true. For example, there are a series of discussions that are taboo in politics, such as income distribution. The Nexus makes it very clear that energy, food and water are needed by people, and that people with different income levels consume very different amounts of energy, food and water.  This type of analysis is uncomfortable.

Tell us very briefly about Multi-Scale Integrated Assessment of Society and Ecosystem Metabolism, MuSIASEM, that you proposed in the book “Resource Accounting for Sustainability Assessment ”?

The MuSIASEM approach is extremely simple, but at the same time complex, because it operates at different levels at the same time. It has two major differences compared to other models: 

  1. It considers the difference between functional vs. structural elements.  For example, how much energy is consumed for transporting oil (function)?  You can transport via a pipeline or a truck, which are two completely different structures implying different energy consumption.  When using an input/output data set, you have to know whether the data refers to functional or structural elements in order to properly use them;
  2. It uses concepts from thermodynamics of non-equilibrium for the definitions of categories of accounting. For example, 1 MJ of electricity is energy for a refrigerator, but it is not energy for a horse. You cannot define what is an energy carrier if you do not first define who or what will be using it. In our accounting system, primary energy sources, energy carriers, and energy users define each other in an impredicative way. 

We are now developing software, videos and a game so that MuSIASEM can be more widely applied and understood. We should have the software and the game ready next year. 


Nexus is not necessarily about conflict, but it does show power asymmetries. For example, we had a student looking at differences in the practices of agricultural production in an area with unsettled conflicts.  She found that the farmers belonging to the ‘establishment’ were using 22 times more water than those who lost the conflict. An analysis of resource uses immediately reveals the existence of power asymmetries in society. Power asymmetries, rather than being reduced, are exploding everywhere.  Nexus analysis is a powerful tool to identify asymmetry of power relations. For this reason the Nexus is challenging for the actual institutional setting as it can be potentially destabilizing. 

When it comes to the issue of sustainability, we are currently in a situation of denial. Rather than admitting “Houston we have a problem”, scientists prefer to adopt the mantra: “give us more money and we can fix it”.  However, if one is serious about considering the implications of the Nexus one should stop the denial, and work hard on how to reframe the sustainability predicament in a more effective way.  This may bring about a revolution in the conceptual framework of sustainability research and governance. For example, many people in the EU think that climate change is the most important problem in the world.  But let’s imagine that you are a young single-mother in a shantytown in Africa where there are only eight toilets available for seven thousand people.  Probably the effect of climate change in 2050 are not among your priorities… 

Final words

The big message of the nexus is that we should try to look at ourselves and try to fix our priorities first. Modern science pretends to look at the world “from the outside” like if scientists were God. But all humans are part of the world, We (scientists) are inside what we observe.  When discussing sustainability, rather than trying to fix nature because it does not behave as we would like, we need to be more reflexive. Humans have to adjust to the constraints given by nature and not the reverse.

The Nexus is a source of uncomfortable knowledge because it challenges the simplified story-telling that currently holds modern society together.  Of course, you cannot have a win-win situation for everybody. You have to adjust and adapt to the resources and limits of the system, you have to look at the different viewpoints of every problem and consider the implications.  That is wisdom, that is Nexus.

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