Belgium plans to close its nuclear energy chapter for good with the shutdown of all remaining reactors in 2025. But the phaseout is far from clear-cut and permitting challenges around new gas-fired capacity could make the transition away from nuclear difficult.

While easterly neighbor Germany has pursued a nuclear exit since 2011 and will close its last plants at the end of this year, and France to the south is doubling down on nuclear as the core of its energy future, Belgium's position is somewhere in the middle.

The federal government pledged to shut down the 3,072-MW Tihange and 2,935-MW Doel plants, which provide almost 40% of Belgium's power, and replace most of the lost capacity with gas. However, strong voices in the local government are calling for the life of the reactors to be extended. Belgium is split administratively into the Flemish-speaking Flanders region and French-speaking Wallonia.

"Some suggest that there is a guerrilla dispute between the federal and the Flemish [regional government] over the future of Belgium's energy mix," said Damien Verhoeven, partner at Belgian law firm Liedekerke.

A nuclear exit could facilitate a renewables drive throughout the 2020s, but like many of its European neighbors, Belgium faces challenges in permitting and grid connections to make that a reality.

Phaseout plan

Due to their age and condition, Belgium's two nuclear plants, owned by France's Engie SA, can only run until 2025. Providing that security of supply is ensured, the plants' seven reactors will be phased out periodically until then. At both plants, initial units began operating in 1975, with additional units added through 1985.

Engie already recorded a €2.9 billion impairment against its Belgian plants in 2020, following a decision to stop extension works, and it has previously said it was fully focused on dismantling all units.

But amid questions over security of power supply in Belgium, the Federal Agency for Nuclear Control, or FANC, said in early January that lifetime extensions are still possible, noting that timing to initiate and complete the works is very tight. "The nuclear exit or a potential lifetime extension is a governmental decision," a spokesperson for Engie said Feb. 8.

According to FANC, a final decision to extend the lifetimes of one reactor each at Tihange and Doel will need to be made in the first quarter.

"It is very likely that we will indeed phase out [nuclear] in 2025," Verhoeven said, adding, "The nuclear phaseout will mainly be tackled by gas plants and imports, as well as storage and demand response."

In order to shore up supply of gas-fired capacity, Belgium launched a capacity market mechanism, in which developers of gas-fired power plants can receive subsidies to develop new capacity. Companies have until March 15 to propose permitted projects for the next capacity market process.

Nuclear divide

Belgium is divided on the question of nuclear power. While the federal energy minister, the Green Party's Tinne van der Straeten, wants to seal the exit from nuclear, right-leaning nationalist authorities in Flanders would like to see the plants' lifespans extended.

In November 2021, Zuhal Demir, the environment minister of Flemish-speaking Belgium, denied a permit to Engie's Vilvoorde gas plant, reportedly citing a lack of paperwork on emissions. Engie resubmitted the application on Jan. 7, according to the company spokesperson. Flanders-based industry, which was hoping for competitively priced power from the plant, had also pushed for approval.

On its website, Flemish party Nieuw-Vlaamse Alliantie, of which Demir is a member, argues for keeping the two newest nuclear power stations open for at least another decade "instead of building more polluting gas-fired power stations."

"The nuclear phaseout will cost us a lot of money and be a step backwards in the fight against climate change," the party says.

Van der Straeten, the energy minister, said in November 2021 the permit rejection "creates legal uncertainty for all industrial projects in Flanders."

If the Vilvoorde project needs to be withdrawn, other projects currently being developed in parallel will be available to meet the shortfall, a spokesperson for Belgian grid operator Elia System Operator SA said in an email.

One project in the running is Eneco Groep NV's plan for a gas turbine in Wallonia. A spokesperson for the company said the group is still in the permitting process and that the company will not build the plant if it does not receive subsidies.

Renewables, imports to rise

The gap left by nuclear could also boost renewables capacity. "Belgium's nuclear phaseout will pave the way for rapid growth of renewables," according to a January report from data analytics firm GlobalData.

The country is expected to overachieve its 2030 renewables capacity targets, beating its 6.5-GW wind power target by just shy of 0.85 GW and its 6.9-GW solar target by 4.9 GW, according to GlobalData estimates.

Despite having a coastline of only about 65 kilometers, Belgium has made strong use of its narrow plot of the North Sea, boasting 2.26 GW of offshore wind capacity, making it the third-largest market in Europe behind the U.K. and Germany. Construction will pause for a few years until a new zone is developed.

For onshore wind, in which Belgium is already a mature market, the country faces siting challenges as new projects come up against local community objections similar to those observed in other European countries. Belgium also requires further reinforcement of grids to accommodate the capacity.

The Elia spokesperson cited analysis showing that Belgium's renewables capacity will grow from 12.45 GW installed today to 17.6 GW by 2026, though much of this will be rooftop solar.

As the deployment of renewables continues, cross-border power exchange will increase as well, but Elia expects the country to draw more power from its neighbors as it shuts its nuclear fleet. "After 2025, Belgium should again become a net importer of electricity," the spokesperson said.