The Belgian government has agreed with French energy giant Enigma on keeping the Doel 4 and Thihange 3 nuclear power plants open until 2035. Engie will also pay 15 billion euros for the future disposal and processing of all nuclear waste.

But on the very day that the deal is knocked off, Elia, the transmission system operator of Belgium’s high-voltage grid, comes out with a report saying that some 2,9 GW of additional capacity will be needed by 2029 due, among other things, to the breakthrough of electric cars, or five years earlier than expected.

From closure to reopening

Belgium has seven nuclear reactors spread across two sites: Doel, in the province of East Flanders, and Tihange, in the province of Liège. Doel has a capacity of about 2,9 GW; Tihange has a capacity of about 3 GW.

On the grounds of the 2003 nuclear phase-out law, all nuclear plants were initially supposed to be deactivated between 2023 and 2025. But due to the Russian-Ukrainian war and sharply – rather insane – rising energy prices, Belgium decided to continue with nuclear power anyway, keeping the two youngest nuclear reactors, Doel 4 and Tihange 3 (1 GW each), open ten years longer than originally planned.

‘Interim’ agreement

The plan now is to restart the latest and already shutdown reactors, with talk of a “preferred scenario” of November 2025. That should ensure the security of supply in the winter of 2025-2026. In the other scenario, it will be November 2026.

However, the modalities for extending Doel 4 and Tihange 3 for ten years had yet to be agreed between Enigma and the federal government. That ‘interim’ agreement was knocked off by both parties on Thursday.

Belgium and Engie will jointly own the reactors that remain open, and the relaunch involves an investment of between 1,6 billion and 2 billion euros, with Enigma and the Belgian state each contributing half of that amount.

Engie will also pay 15 billion euros for the processing of nuclear waste. Any additional costs will be borne by the Belgian government, i.e. taxpayers, the reason why environmental organizations such as Bond Beter Leefmilieu, Greenpeace, and Canopea warn that “this could become the biggest hold-up in Belgian history”.

According to Energy Minister Tinne Van der Straeten (Groen), this criticism is unjustified. “The volume risk remains with Engie. If there is more waste than expected, the company will pay for it,” she said in the newspaper De Morgen.

Including the cost of dismantling the nuclear plants, the bill for Engie runs to at least 23 billion euros – the nuclear piggy bank Synatom, a subsidiary of Engie, already holds 14,3 billion euros.

Elia warns fora dditional capacity

However, high-voltage grid operator Elia expects a sharply increasing electrification of the mobility, heating, and industrial sectors in the coming years. This will create additional capacity needs. This is according to the adequacy and flexibility study Elia made for Belgium for 2024-2034.

Indeed, according to Elia, society is electrifying earlier and faster than expected. Due to the switch from an industry running on fossil fuels to electricity, the breakthrough of EVs, the associated network of charging stations, and the heating of homes with heat pumps, for example, Elia expects Belgium’s electricity consumption to increase by 60% over the next ten years.

According to Elia, introducing the capacity reminder mechanism (CRM) is the first crucial lever to maintain the security of supply. That CRM now needs further refinement, says Elia.

The mechanism, introduced in 2021 to ensure the security of electricity supply after the planned closure of nuclear power plants, grants support through annual auctions to units that can supply or save electricity from 2025 onward. It also avoids excessive profits by including an obligation to repay the support received in case of high prices.

From 2,9 GW to 3,4 GW

However, on top of the extension of the two latest nuclear power plants, Elia expects that some 2,9 GW of additional capacity will be needed by 2029 (or some 700 megawatts per year) and 3,4 GW by 2034.

Those capacity needs can be partly mitigated by encouraging flexible consumption for the charging of EVs, with more consumption off-peak at a lower price. Or by battery parks and deploying new sources of flexibility, such as demand management, as soon as possible. Because delays in unlocking flexibility or realizing grid infrastructure will lead to additional capacity needs, according to the grid company.

No further postponement of investments

In the long term (2030-2032), Elia stresses the importance of timely commissioning of the Princess Elisabeth zone – the zone of wind turbines off the Belgium coast – and additional interconnectors with the UK (Nautilus) and Denmark (TritonLink).

After 2033, capacity needs will increase again due to the uprise of electrification. Therefore, additional offshore capacity needs to be prepared and planned in the coming years, and Belgium has an interest in concluding agreements and developing interconnectors with countries that have a production surplus.

If Belgium makes full use of its industrial and residential flexibility and realizes its planned investments, such as Boucle du Hainaut, Ventilus, HTLS upgrades, Nautilus, and TritonLink, the capacity needs will decrease by 3 GW by 2034, according to Elia, compared to a situation in which those steps are postponed.