What levers are employed by the models to achieve emission reductions?

  • Level of emissions reduction in WWH ranges from -33 to -64%.
  • The driving force, which refers to the activity variable that increases emissions in a sector, is “power generation” in the electricity supply sector. In all models and scenarios, power generation has a positive contribution to emissions.
  • Renewables are employed with varying magnitude for decarbonisation: their contributions range from -31% relative emission reduction in NEMESIS to -74% in GCAM.
  • The share of nuclear in the power mix decreases in all models except for GCAM, where the share of nuclear stays almost constant at around 27% of power generation. For the other three models, the impact is on a comparable level (11-16% of emission increase).
  • The contribution of the fossil CO2 intensity reduction to decarbonisation is very small in all models.
  • The application of CCS to reduce emissions starts in 2035 for GCAM and EU TIMES, it is not used in the other two models. Only in GCAM, CCS already has a large contribution to decarbonisation in WWH (-58%). In EU TIMES, it contributes -13% to emission reduction. 

Screenshot 2024 12 17 at 16.42.19

How do the models compare over time based on benchmarking indicators?

  • “Energy intensity” is a measure of energy used per unit of GDP.
  • In the WWH scenarios, the indicators are on different levels in 2020 and then decrease towards 2050 for all models except EU Times.

Screenshot 2024 12 17 at 16.42.47

Methods

Description of Index decomposition analysis (IDA):

  • A changing variable such as sectoral CO2 emissions over a time period (2020-2050) is decomposed into its factors of influence such as the sectoral activity, its energy efficiency, and its CO2 intensity
  • Identification of key driving forces and levers of emission changes over time
  • Results of the updated first and second modelling rounds, consisting of the "Where we are headed" (WWH) and Net Zero Emissions (NZE) scenarios for the EU28
  • The IDA allows identifying the chosen emission reduction levers for different scenarios within one model as well as between models.
  • IDA aims to improve the link between climate science and policy by increasing the transparency on the range of contributions from CO2 reduction levers

Description of sector benchmarking indicators:

  • Comparison of the results of different energy-system and integrated assessment models available in the project with the sector models, FORECAST and ALADIN
  • Based on selected indicators such as electrification rate and CO2 intensity.
  • WWH and NZE scenarios
  • ALADIN and FORECAST used as a benchmark to assess the ranges of several indicator results of the EU models over time.