Comparing energy system optimization models and integrated assessment models: Relevance for energy policy advice

Area of Science:

• Climate Change Modelling
• Energy Systems Analysis
• Environmental Policy

Background:

• Transitioning to a climate-neutral society requires robust planning tools like Integrated Assessment Models (IAMs) and Energy System Optimisation Models (ESOMs).
• While common in European policy, IAMs and ESOMs have rarely been directly compared or linked.
• This gap limits comprehensive understanding and effective policy design for climate goals.

Purpose of the Study:

• To conduct an explorative comparison of 11 IAMs and ESOMs within the European Climate and Energy Modelling Forum.
• To identify potential information flows and establish harmonised regions and shared variables for cross-model scenario comparison.
• To enhance the interpretation of modelling results for policymakers and researchers.

Main Methods:

• Comparative analysis of 11 Integrated Assessment Models (IAMs) and Energy System Optimisation Models (ESOMs).
• Identification and comparison of regional aggregations and commonly reported variables across models.
• Definition of harmonised regions and a shared subset of result variables for cross-scenario analysis.

Main Results:

• Power generation and demand are interconnected, influenced by regional and sectoral drivers.
• Demand for energy carriers like hydrogen can be linked to renewable power generation potentials, such as onshore wind.
• The utilization of nuclear power shows a correlation with the availability of wind resources.

Conclusions:

• Cross-model comparisons improve the interpretation of IAM and ESOM results for climate policy.
• There is a need for community standards in region definitions and variable reporting to facilitate future model comparisons.
• Regional aggregations in models may obscure national-level variations, highlighting the importance of national-level analysis for policymakers.