Summary of the ERAA

The European Resource Adequacy Assessment (ERAA) is a pan-European monitoring assessment of power system resource adequacy of up to 10 years ahead and is the successor of the Mid-term Adequacy Assessments (MAF). It is based upon a state-of-the-art probabilistic analysis, aiming to model and analyse possible events with potentially adverse consequences for the supply of electric power and will be the central reference point to take qualified decisions on strategic matters such as the introduction of capacity mechanisms (CMs).

Purpose and Motivation of the ERAA

Due to the increasing level of variable renewable energy sources in the European power system and the associated challenges for system development and operation, a pan-European analysis of resource adequacy has become ever more important. Cooperation across Europe is necessary to accelerate the development of common methodological standards.

The ERAA will provide stakeholders with the data necessary to make informed, qualified decisions and promote the development of the European power system in a reliable, sustainable and connected way. It will assess the balance between net available generation and net load levels in the European power system on a continuous basis.

The ERAA should not be interpreted as an effort to predict the system’s security of supply but rather as a measure of the grid’s ability to maintain security of supply under a very high number of possible future grid states, due to different plausible climate conditions and random outages.

The Evolution of MAF to ERAA under the Clean Energy Package (CEP)

With the coupling of European energy markets, the integration of renewable energy sources and efforts to decarbonise energy systems, adequacy monitoring needs to be intensified. In the current fast-paced landscape, the ERAA, i.e. the annual screening of adequacy in Europe for the upcoming decade, must provide input for strategic decisions regarding, for instance, the introduction of CMs. The ERAA methodology, as approved by ACER on 2 October 20201, 2, has introduced significant changes and its stepwise implementation has begun in 2021. The MAF 2020 was thus the last MAF report anterior to the ERAA implementation.

What are the upcoming challenges and future steps for resource adequacy?

The ERAA methodology foresees several new assessment approaches and modelling features which come with the corresponding efforts and challenges. The main methodological features of the future ERAA include:

  • Increase of the time horizon to 10 target years with an annual granularity
  • Consideration of the climate change impact on assessing adequacy
  • Implementation of an Economic Viability Assessment
  • Replacement of Net Transfer Capacities by a Flow-Based Market Coupling approach
  • Consideration of sectorial integration

As the implementation of the ERAA is complex and time-consuming, it will be achieved by ENTSO-E in a stepwise manner and was initiated during the execution of MAF 2020 (Figure 1).

ERAA Figure 01

Figure 1: European Resource Adequacy Assessment Methodology Implementation – Principle Roadmap (Version date: 10.12.2020)

The ERAA 2021 is the first implementation of the ERAA methodology and aims at performing proof-of-concept (POC) studies for the future implementation of the economic viability assessment and flow-based market coupling for a scenario with and a scenario without capacity mechanisms. ERAA 2021 will also consider climate change using a transitionary solution while waiting for an updated Pan-European Climate Database.

The 2021 assessment is ongoing and will be carried out for two target years (TY), namely 2025 and 2030. TY 2025 was chosen as it represents a pivotal year for evaluating adequacy due to expected reductions in coal and nuclear capacity in Europe. TY 2030 was chosen to allow for the evaluation of the adequacy situation further ahead, at the end of the 10-year time horizon. Both TYs allow for a comparison with MAF 2020 results. The ERAA, which considers the medium term, is also coordinated and consistent with other timeframe studies as the Ten-Year Network Development Plan (TYNDP) and Seasonal Outlook.