A Review of Belgium Energy Policy Under the Vivaldy Coalition: A difficult Journey Toward a Net-Zero Society.

Highlights

From 2020 to 2024, the Vivaldi government — led by Green minister Tinne Van der Straeten — pushed to phase out nuclear, expand renewables, and electrify key sectors, aiming for affordable, low-carbon electricity.

But what are the results, one year later?

• Low-carbon electricity fell from 66 to 53 TWh, as the loss in nuclear outweighed the rise in renewable. Belgium became the only country in Europe to reduce its low-carbon generation during an energy and climate crisis.

• Growth in wind and solar is now slowing, while grid stability and dispatchability remain unresolved.

• Electricity prices are still above pre-crisis levels, and electrification of key sectors has stalled.

• With Doel 1, 2 and Tihange 1 closing in 2025, further decline is expected.

• Belgium has become increasingly reliant on importing electricity, and this dependence is expected to grow in the future.

  
  

Introduction

Between 2020 and 2024, the Vivaldi coalition, led by Energy Minister Tinne Van der Straeten of the Green Party, has driven Belgium's energy transition following the 2020 government agreement. The coalition prioritized sustainability, security of supply, and affordability, focusing on expanding renewable energy sources like wind and solar while phasing out nuclear energy. To keep electricity affordable, the government promoted a competitive market to drive down prices while ensuring supply security through regulatory bodies responsible for overseeing pricing and system stability. The nuclear phase-out, based on the 2003 law, remains a guiding principle for the Green minister. Nonetheless, the 2020 government agreement left the door open to maintaining 2 GW of nuclear capacity if needed for security of supply. Strategic reserves, demand management, and storage solutions were also considered to ensure supply after the complete nuclear phase out. Furthermore, the coalition aimed to electrify sectors reliant on fossil fuels, such as transportation, heating, and industrial activities, to significantly reduce carbon emissions and expedite the energy transition.

One year after the end of the Vivaldi coalition and the arrival of the new Arizona coalition, we review the results of the energy policy led by Minister Van der Straeten. Our assessment focuses on five key areas: national low-carbon energy generation, domestic electricity consumption, annual cross-border electricity exchanges, and the evolution of electricity prices.

Low carbon electricity generation

Over a span of four years, there has been a decline in low-carbon electricity generation, primarily driven by the reduction in nuclear energy production and the insufficient growth in renewable energy deployment.

Nuclear energy continues to dominate but declines rapidly: In 2021, nuclear energy accounted for 48 TWh of the electricity mix, representing the majority of low-carbon electricity. However, this figure decreased to 30 TWh by 2024, marking a 37.5% reduction over four years. This decline is due to the shutdown of Tihange 2 (on October 1, 2022) and Doel 3 (on February 1, 2023) nuclear reactors, in line with the 2003 nuclear phase-out law, which is supported by the Vivaldi coalition but publicly contested by some members, particularly from the Reformist Movement (MR).

Intermittent renewable sources show growth or stability: total renewable generation grew from 16 TWh to 21 TWh in four years. Solar energy increased from 5 TWh in 2021 to 8 TWh in 2024. Offshore wind remained stable at 7-8 TWh, while onshore wind rose from 4 TWh to 6 TWh.

Even though electricity generation from nuclear energy has declined, nuclear power plants have maintained good availability throughout the four years of the Vivaldi coalition, experiencing limited forced outages. Installed capacity decreased from 5940 MW in 2021–2022 to 3940 MW by 2024 due to the shutdowns of Tihange 2 and Doel 2. Despite these closures, average output remained high, indicating efficient operation of the remaining reactors. Average availability rate reached 91 % during the 4 years studied period. This demonstrates that even if the average age of the nuclear fleet increases, it has no impact on the availability of the fleet. However, the minimum output level dropped significantly (from 4189 MW in 2021 to 2282 MW in 2024), this was caused by the reduction of installed capacity but also by a short period of unavailability of nuclear units (only 2 days), when between 24 and 26 of June 2022, Doal 4, Doel 1, Thiange 1 and Thiange 2 were not operational resulting of an output of only 2978 MW out of 5940 MW.

Nonetheless, this situation stands in stark contrast to November 2018, when only one unit (980 MW) was operational. At that time, former Energy Minister Marghem introduced a load shedding plan to prevent a nationwide electricity shortage, although the plan was ultimately never activated.

Despite the overall growth in renewable energy generation, its output remains variable and heavily influenced by weather conditions, as illustrated in the figure below. The number of hours during which renewable supplied less than 5% of Belgium’s electricity consumption has remained significant. For instance, in 2024, renewable provided less than 5% of the national electricity demand for 15% of the year (1,356 hours out of 8,760). Occurrences when renewable energy contributed less than 1% of national electricity consumption remain rare but have not disappeared. In fact, they even increased in 2024, reaching 328 hours.

These events—when renewable energy contributes less than 5% of electricity demand—can occur for a notable number of hours each year and often extend over several consecutive hours. The graph below illustrates the number of instances when such events lasted more than 4, 8, or 12 hours.

While there is an overall downward trend in the number of occurrences from 2021 to 2024, events lasting more than 4 hours remain relatively frequent. In 2024, for example, 142 such instances were recorded, reflecting the inherent variability of weather-dependent sources like wind and solar. The slight increase in events between 2023 and 2024 for both the 4-hour and 8-hour durations suggests that year-to-year weather variations continue to influence renewable generation levels, even as installed capacity grows.

Longer events—those exceeding 12 hours—have decreased over time, from 58 occurrences in 2021 to 31 in 2024. However, these extended periods of low renewable output can present operational challenges, particularly during times of high electricity demand or reduced availability of complementary sources. This data also highlights the importance of system flexibility and diversified solutions. While battery storage can help manage short-term variability, its current typical discharge duration of around 2.8 hours may not always align with the length of renewable shortfalls. (According to Elia's adequacy study for 2026-2036, by the end of 2024, batteries already connected to the grid have a duration of 2.8 hours.)

Belgium electricity generation capacity

Between 2021 and 2024, Belgium significantly increased its solar capacity from 6,8 GW to 10.6 GW, making it the fastest-growing energy source in terms of installed capacity; however, this expansion resulted in only a 3 TWh increase in electricity generation over four years. Those 3 TWh accounts for approximately 1% of Belgium's total electricity consumption, highlighting the significant solar capacity required to achieve a fully renewable electricity system.

This reflects the Vivaldi coalition commitment to expanding renewable energy production. Onshore wind grew moderately, while offshore wind remained stable. Nuclear capacity decreased from 5.9 GW to 3.9 GW, reflecting the beginning of nuclear phase-out. Fossil gas capacity remained steady, highlighting its role in balancing variable renewable. Overall, the energy mix is shifting, but flexibility and backup remain essential. Due to the closure of dispachable power capacity, it is very likely that Belgium will have to increase the need for gas capacity to ensure a stable supply to the grid.

This is demonstrated by the ongoing construction of the 2 largest gas power plants in Europe. One located in Seraing with an installed capacity of 870 MW, and the other in Flemalle with 805 MW of installed capacity. Moreover, according to assessments made in the Elia adequacy study 2026-2036, new gas power plants (CCGT) could be required from 2028 onward and even more after 2035, once the 2 last nuclear power plant will be shut down (depending of various electricity consumption scenarios).

Writer Comment : Elia assesses that flexibility could play a major role to prevent the construction of new gas power plants, but I do not share this vision with such optimism. While flexibility is beneficial for the energy transition, its impact is currently limited, with only about 1 GW of demand difference observed between 2015 and 2025 during peak consumption hours. Flexibility will start to have a significant impact only when electrification becomes a more prominent part of the final energy consumption mix as it can be already seen in Norway or in Finland. In the figure below, you can find the "GAP" that needs to be fill to avoid electricity shortage based on the adequacy study 2026-2036 and the different scenarios exposed in the study.

The total solar capacity expanded considerably from 3.0 GW in 2014 to 10.6 GW in 2024. The annual growth rose sharply from 0.1 GW between 2014 and 2015 to 1.75 GW in 2023, with a slight decrease to 1.35 GW in 2024. The most significant increases were observed from 2019 onward, particularly between 2022 and 2023. The important increase in 2023 en 2024 has been primary driven by the increase of electricity price during the energy crisis. Nonetheless, futur growth is expected to slow down in the coming years. Indeed, due to the end of the crisis (2022-2023), electricity prices have dropped, making conditions for the deployment of new installed capacity less economically. Moreover, grid limitation and the reduction of state aid will likely not play a role in the increase of new added solar capacities in Belgium.

During the 4 years of Vivaldi coalition (2021-2024) wind onshore capacity has continue to growth from 2757 MW to 3393 MW. Nevertheless this increase has slow down mainly in 2023 and 2024 and more specifically in Flanders with the construction of only 19 wind turbines in 2023 and 12 in 2024. Moreover, the capacity factor of wind turbine have decreased with time, causing a stagnation of wind onshore generation. In the near, medium, and long term, the growth rate of onshore wind is unlikely to increase significantly, as a large portion of efforts will need to focus on replacing aging wind turbines. Nonetheless, this could change depending of political will and additional policies that could be put in place by new governments (at the regional level). Indeed, to maintain overall growth, the installation rate would need to be high enough to both re-power existing turbines and add new capacity simultaneously. This issue is already visible in Germany, where the country is unable to cope with the speed of dismantelling old wind turbines and the construction of new ones. This slow down the rapid expansion needed to reach a 100 % renewable electricity system.

Belgium Electricity Consumption

National electricity consumption remained stable over the past four years, except during the 2022/2023 energy crisis. Although electricity consumption is anticipated to rise over time, this has not yet occurred, despite Elia's projections based on public and industrial statements regarding future electrification (including the electrification of industrial processes, transport, and heating). This highlights a significant challenge for Belgium's energy transition, as most carbon thermal systems need to be replaced by low-carbon electric generation systems. According to Elia studies, electrification will be the biggest player in the decarbonisation of our economy on the condition that electricity is available for future consumers at a low price and generated by low-carbon sources.

4.  Annual Cross-border Electricity Exchanges

Belgium's electricity balance transitioned from a surplus of 7.6 TWh in 2021 to a deficit of 10.8 TWh in 2024, highlighting an increased dependence on imports. Throughout this four-year span, Belgium has remained a net exporter of electricity to the United Kingdom, while increasingly importing more from the Netherlands and France. During France's nuclear corrosion crisis, Belgium provided 9.8 TWh of electricity to France, even though it became a net importer of 12.6 TWh of electricity from this country in 2024. Since 2023, Belgium has been importing electricity generated from nuclear power in France and from the Netherlands, which has a higher CO2 emission per KWh than Belgium. This importation of electricity generated in France with nuclear energy demonstrate a paradox in the Belgium nuclear phase out policy. In the near and medium term, importation is likely to persist due to the shutdown of new nuclear capacities and the insufficient development of renewable energy capacity.

Evolution of Electricity Prices

From 2016 to 2020, electricity prices were stable and low across four countries, ranging between €35 and €42/MWh, representing typical market conditions. In 2021, prices rose significantly to €99–€109/MWh due to recovering demand post-COVID-19 and early market volatility. In 2022, prices surged dramatically, with the Netherlands at €276/MWh, France at €242, Belgium at €245, and Germany at €235, driven by the European energy crisis linked to geopolitical tensions and supply chain disruptions from the Russia-Ukraine conflict. By 2023, prices dropped to €96–€97/MWh, indicating stabilization but still above pre-2021 levels. In 2024, prices declined further, with France at €58/MWh, and moderate decreases in the Netherlands (€77), Germany (€80), and Belgium (€70), suggesting market normalization. Overall, the chart shows volatility with a peak in 2022 and gradual stabilization, yet prices remain above 2016–2020 levels.

Despite Energy Minister Tinne Vanderstraeten's intentions, electricity prices have remained uncontrolled during the legislative period. However, this increase was mainly due to external factors beyond the minister's control. 2024 electricity prices continue to be higher than the 2016-2020 average price, which indicates a negative sign for the electrification of the rest of society. Indeed, industrial actors may postpone their investment in electric heat processes due to a too high price of electricity generation putting at risk the energy transition.

This concern over high electricity prices remains an issue for the decarbonisation and the competitiveness of the EU/Belgium. As expressed in the Draghi report on EU competitiveness, energy prices remain 5 times higher compared to the US and might limit the decarbonisation speed of the EU. Even two years after the energy crisis, electricity prices are still linked to gas prices, which continue to be the primary determinant of electricity costs according to the merit order pricing mechanism.

Conclusions

• Throughout Tinne Van der Straeten's four-year term, low-carbon electricity production decreased from 66 to 53 TWh. While renewable energy saw a rise of 5 TWh, nuclear generation dropped by 18 TWh. This decline in nuclear output is equivalent to nearly 13 years of renewable energy progress in Belgium.

• Belgium is the only country in Europe that has reduced its national low carbon energy generation in the middle of a climate and energy crisis despite demands from the population to take necessary steps to reach a carbon neutral society.

• Tihange 3 and Doel 4 nuclear reactors can continue to operate until 2036.

• Growth in solar was evident, especially during the energy crisis, but growth in the deployment of newly installed capacity is unlikely to be maintained in the short and medium future.

• Construction of new additional wind turbines has decrease especially during 2023-2024 years and will likely not increase in the short and medium future.

• The issue of grid stability and the non-dispatchable nature of solar and wind energy generation remains largely unresolved at present.

• The anticipated increase in electricity consumption has not yet begun, which is worrisome for the decarbonization efforts in the transport, heating, and industrial sectors, as these sectors are major contributors to our CO2 emissions.

• While electricity price have decreased since 2022, it remains above 2016-2020 average price and will likely not decrease in the short and medium term. The adoption of renewable energy has not necessarily resulted in lower electricity prices

• Belgium has shifted from being a low-carbon electricity exporter to an electricity importer, making it more dependent on its neighbors. Most of its electricity imports come from France, which primarily generates its power using nuclear energy.

• The shutdown of Doel 1, 2, and Tihange 1 in 2025 is highly likely to lead to a reduction in low-carbon electricity generation in the following years (further analysis on this topic will be released in the upcoming weeks).

Data From : Energy-charts, Elia Adequacy study, Renouvelle.be, The Draghi report on EU competitiveness.