Adequa cy an d flexibility study 2026-2036 _ P. 200 STUDY REPORT _ P. 201 RESULTING MARGINAL COST FOR EACH TECHNOLOGY The computation of variable costs is presented in the equation below: Variable cost [€ ⁄ MWh] = Variable O&M cost [€ ⁄ MWh] + + CO2 emission factor [tons ⁄ GJ] x 3.6 [GJ ⁄ MWh] efficiency [%] x CO2 price [€⁄tCO2] Fuel price [€ ⁄ GJ] x 3.6 [GJ ⁄ MWh] efficiency [%] TABLE 5-2: ASSUMPTIONS REGARDING FIXED COSTS AND OTHER ECONOMIC PARAMETERS It is also possible to visualise the merit order in a figure for a certain year. The international merit order for 2026 is provided in Figure 5-15. This only includes thermal generation capacities. It is also important to note that certain units are subject to ‘must run’ constraints and hence their marginal cost is not the only driver for their dispatch. The shape of the merit order and hence the position of each unit is a key parameter that will influence its revenues from the electricity market. Technologies part of the structural block CCGT OCGT Energy only market hurdle (real WACC + premium) 2025-2036 2025-2036 2025-2036 2025-2036 Applies to 20312036 20252030 Existing units <25 years - 37 - - 7.2% - 28 - - 7.2% 35 - - 7.2% Turbojets All existing capacity - 36 - - 7.2% Demand Response All existing capacity - 12 - - Not considered Pumped Storage All existing capacity - 31 - - Not considered CCGT OCGT 350 CCGT Existing units >25 years Lignite Hard Coal OCGT Gas CHP Oil 32 <1 15 8.8% 30 <1 15 8.8% >800 MW 870 (+) 32 3 20 9.8% 1,050 (+) 32 3 20 9.8% < 400 MW 1,300 (+) 32 3 20 9.8% 39 3 20 9.8% 10.8% - 1,160 (+) >100 MW 680 (+) 30 2 20 <100 MW 1,240 (+) 30 2 20 10.8% 34 2 20 10.8% 36 2 20 9.8% 26 <1 1 7.8% 52 <1 1 7.8% 78 <1 1 7.8% 105 <1 1 7.8% H2 fueled >100W Biomass 120 (+) 100 (+) 400 < 800 MW H2 fueled >800W Nuclear 250 Investment economic lifetime [years] - €/MWh 300 Construction period [years] All existing capacity Existing (assuming extension costs needed) Marginal cost by cumulative capacity in 2026 FOM [€/kW/years] CHP Existing (assumed no extension costs) FIGURE 5-15 — MERIT ORDER OF INDIVIDUALLY MODELLED THERMAL UNITS FOR SELECTED COUNTRIES IN 2026 CAPEX [€/kW] - New capacity < 100 MW 930 (+) 1,240 (+) New capacity 0 < 300 MW 200 New Demand Response 150 New capacity 300 < 600 MW All cost included in FOM New capacity 600 < 900 MW New capacity 900 < 1,200 MW 100 50 Large scale batteries (1h) 330 (-) 330 (-) 27 1 15 7.8% batteries Batteries/Storage Large scale (2h) 560 (-) 520 (-) 27 1 15 7.8% Large scale batteries (4h) 1,040 (-) 940 (-) 27 1 15 7.8% New unit 2,300 2,300 20 4 25 Not considered Pumped Storage - new unit 0 0 40 80 120 160 200 240 GW Renewables * Selected countries: France, Germany, United Kingdom, Denmark, Italy, Poland, the Netherlands and Belgium Marginal cost in euro 2024 New 5.2.7 FIXED COSTS OF EXISTING AND NEW CAPACITIES Fixed costs can be divided into two categories: — Fixed Operation and Maintenance (FOM) which are expenses necessary to operate or make any generation, storage, or demand-side response capacity available; these costs are independent of the unit’s output. — Capital Expenditures (CAPEX) which are investments required for new capacities or existing ones seeking to extend their lifespan. Additionally, to assess the economic viability of both existing and new capacities, other economic parameters related to fixed costs must be defined: — the Weighted Average Cost of Capital (WACC) and hurdle premium; — the economic lifespan and construction period of each investment. For each type of capacity considered in the economic analysis, these parameters are used to determine the economic viability of existing and new capacities in the electricity market. Since it is impractical to determine the exact costs for each new or existing capacity individually, a central value is used based on various sources. These values were put out for public consultation and adjusted after receiving feedback from stakeholders. The values for the WACC and hurdle premiums are up to date based on the latest information for the current study and after calculation by the Professor Boudt. These calculations can be found on Elia’s website [ELI-6]. The details regarding the other assumptions and sources used are provided in the following sections. Table 5-2 provides an overview for new and existing capacities per technology of the previously mentioned fixed parameters. Table 5-3 provides an overview of the sources looked upon for the economic parameters presented in table 5-2. All costs are adjusted for inflation compared to the public consultation and are here shown in € ‘end of 2024’. Wind onshore New 1,330 1,250 32 1 15 7,2% Wind offshore New 2,300 2,170 62 3 20 7,2% Utility Scale PV New 670 630 13 1 15 7,2% Biomass New 3,030 2,950 98 3 20 Not considered (+) A sensitivity with 20% increase in costs is performed. (-) A sensitivity with 20% decrease in costs is performed. TABLE 5-3 — SOURCES USED FOR FIXED COSTS AND OTHER ECONOMICS ASSUMPTIONS Gas fired Pumped storage CRM 2024 Document de consultation publique [CRE-1] NREL 2023 Adeqflex 2023 2023 Adequacy and Flexibility study for Belgium (2024-2034) [ELI-18] 2023 Electricity ATB Technologies and Data Overview [NRE-3] Elia 2023 ENTRAS 2024 Update on Cost of Capacity study [ELI-15] Adequacy & flexibility study for Belgium (2024-2034) [ELI-18] NREL 2024 Annual technology Baseline [NRE-2] Lazard 2024 2024 Levelised Cost Of Energy [LAZ-1] EIA 2024 Capital Cost and Performance Characteristics for UtilityScale Electric Power Generating Technologies [EIA-1] Gas Turbine World 2024 Gas Turbine World Handbook 2024 [GTW-1] Battery storage NREL 2024 Annual technology Baseline [NRE-2] EIA 2024 Capital Cost and Performance Characteristics for UtilityScale Electric Power Generating Technologies [EIA-1] Elia 2023 Adequacy & flexibility study for Belgium (2024-2034) [ELI-18] RTE 2024 Bilan prévisionnel 2023 [RTE-3] Wind, solar, biomass NREL 2023 2023 Electricity ATB Technologies and Data Overview [NRE-3] EC 2021 EU Reference Scenario 2020 [EUC-15] RTE 2024 Bilan prévisionnel 2023 [RTE-3] IEA 2020 Projected Costs of Generating Electricity 2020 [IEA-8] EnergyVille 2023 PATHS 2050 - Scenarios towards a carbon-neutral Belgium by 2050 [EVI-3] Lazard 2023 2023 Levelised Cost Of Energy+ [LAZ-2] IEA (World Energy Outlook) 2023 Renewable Power Generation Costs in 2022 [IEA-9] Demand Side Response CRE 2021 Study on the functioning and price evolution of the Belgian wholesale electricity market [CRE-2] Compass Lexecon 2017 Assessment of the impact of the Polish capacity mechanism on electricity markets [PLC-1]

Adequacy and flexibility study for Belgium (2026-2036)