With its professional simulations model, SimelSP3, 100TWh has analysed the Belgian electricity system. The objective was to assess the impact of the shutdown of 4 GW nuclear capacities (on 6 GW) in 2025 on the cost of electricity, and the need for the replacement of the nuclear dispatchable capacity by gas or from imports.
The model incorporates hourly load data, renewable production profiles, and investment costs for generation and storage technologies. Cost of CO2 can also be included.
It has been calibrated with 2024 data from ENTSO-E and Elia serving as inputs.
Several key findings emerge :
- Nuclear power remains a cornerstone of affordability and security. Simulations show that keeping our original nuclear capacity could drastically reduce electricity costs, and the need for dispatchable backup from gas or imports.
- Renewables are contributing but are not sufficient alone. Solar and wind play a role in the decarbonization of the Belgian power system, but additional dispatchable means are needed. Further “hidden costs” arising from the flexibility requirements are not modelled here, in particular grid adaptation costs in case more renewables would be considered to replace gas.
According to our simulation, for Belgium, the cost of the Nuclear Exit end of 2025 is :
3,2 Billions €/year
<see our study report>
