Transition to net-zero carbon is not merely technical but a complex socio-political endeavour with significant trade-offs involving inequality, well-being, sustainability, and political acceptability. While significant progress has been made in understanding the biophysical dimensions of climate change, the socio-political aspects remain largely underexplored by assessment models. The Working Paper “Transitioning towards Harmonious Living: A Society-Economy-Nature model with heterogeneous agents, finite resources and politics (SEN-HARP) for Europe-27” by SPES Researchers from the University of Bordeaux introduces the very innovative SEN-HARP model as a useful tool for analysing more comprehensively the trade-offs between effectiveness, fairness and political feasibility brought by the net-zero carbon transition.
The SEN-HARP is a Agent-Based Model which integrates biophysical and socio-political modules through original feedback loops to study how these interactions might shape the feasibility and effectiveness of different scenarios of European Union’s Green Deal: market-based and innovation, augmented Green Deal, and a disruptive post-growth called “harmonious living”.
The SEN-HARP model articulates the micro and macro levels for simulating the joint dynamics of resource use, warming impacts, livelihood dynamics and voting behaviour, the latter being based on perceived gains or losses from transition policies. By combining an Agent-Based Stock-Flow Consistent (AB-SFC) approach with an environmental biophysical module, SEN-HARP can also explore how sustainability goals interact with inequality and political acceptability within fiscal and physical boundaries. The model also gathers the AB-SFC approach with an environmental bio-physical module and an accounting of provisioning systems as well as voting behaviour.
By integrating the biophysical and socio-political modules within a Stock-Flow Consistent framework, the SEN-HARP model allows to explore scenarios in which the pursuit of sustainability goals interacts with the dynamics of inequality and political acceptability in the context of EU27.
For example, it is possible to examine how different policy instruments—such as carbon taxes, subsidies for renewable energy, or universal basic income—affect the distribution of costs and benefits, and how these distributional outcomes influence political support for the transition.
Or, it is also possible to investigate the conditions under which synergies between sustainability, well-being, and political acceptability emerge, as well as the trade-offs that may arise when these objectives conflict.
The model is also fitted to simulate scenarios of carbon transition in democracies, that is under the pressure of votes. As the model is calibrated for EU27, it allows jointly assessing the conditions of socio-political feasibility and environmental effectiveness of the European Green Deal2 in the context of a European democracy modelled as a two-party (pro- and anti-transition) system.
In a context of high (geopolitical) turbulence, it is utterly important to save the European Green Deal by providing ways forward compatible with what European populations are likely to accept in terms of social model, political liberties and economic objectives.
The Working Paper 9.1″Transitioning towards Harmonious Living: A Society-Economy- Nature model with heterogeneous agents, finite resources and politics (SEN-HARP) for Europe-27” is part of Task 9.1 “Synthesizing the evidence on synergies and trade-offs in the making of a just transition” / Work Package 9. The report has been written by Pierre Funalot – SResearcher of the SPES project, Bordeaux University, Bordeaux School of Economics; Eric Rougier – Team leader and researcher of the SPES project, Bordeaux University, Bordeaux School of Economics; Maïder Saint Jean – Researcher of the SPES project, Bordeaux University, Bordeaux School ofEconomics.
