Solar power has become the largest source of electricity produced in Luxembourg, according to new figures from the Luxembourg Institute of Regulation, marking a shift in the part of the energy system the country generates for itself.

The change is narrow but important. It does not mean Luxembourg has escaped its dependence on imported energy; it means that, within the electricity produced on Luxembourg territory, solar has moved ahead of every other source.

Photovoltaic production reached 627 GWh in 2025, up 74.3% from the previous year, ahead of wind power at 467 GWh, wood waste at 398 GWh and gas-fired cogeneration at 63 GWh.

A recent Paperjam report showed that applications for photovoltaic grants had more than quadrupled between 2023 and 2025. The new ILR figures show how that rollout is feeding into electricity production.

A narrow shift

Imports still covered 72% of the electricity available to Luxembourg in 2025, down from 80% in 2020, while electricity produced domestically from renewable sources rose from 16% to 26%.

Installed photovoltaic capacity rose 35.8% to 746 MW, while the number of photovoltaic installations increased by 10,694 to 33,304. Total electricity production on Luxembourg territory rose 20.8% to 1,826 GWh.

The figures do not show a clean substitution story in which more solar automatically means lower gas use. Total electricity consumption rose 2.98% in 2025, while gas consumption also increased, by 1.54%, and gas imports remained almost equal to total gas demand.

That makes the shift significant but limited. Luxembourg is changing the electricity it produces itself, while the wider energy system remains shaped by imported electricity and gas.

The contrast with older domestic-production choices is sharpest in gas-fired generation. Twinerg, the combined-cycle gas plant in Esch-sur-Alzette, was financed at the turn of the century, commissioned in 2002 and closed in 2016, after a much shorter operating life than initially expected.

Solar panels are not free of environmental impact, including manufacturing and supply-chain emissions. The distinction in the ILR data is narrower: Luxembourg’s leading home-grown electricity source now generates power without burning imported fossil fuels, even as measured electricity and gas consumption both rose in 2025.

At the source

The clearest sign of a more decentralised system was the growth in electricity produced and used on site, or shared locally, rather than bought through the grid in the usual way.

These volumes more than doubled in 2025, rising 122% to 444 GWh, and now represent 7% of the electricity consumed by final users. In residential settings, the trend mainly reflects households using electricity produced by their own photovoltaic panels.

The shift helps explain why total electricity use rose while the amount taken from the networks barely moved. Overall electricity consumption, including network losses, increased to 6,529 GWh, but the amount drawn from the grid stagnated at 5,953 GWh.

Bills still rise

The regulator also published its first figures on electricity storage, counting 9,843 batteries at the end of 2025, 98% of them with capacity below 30 kWh. Total storage capacity stood at 101,104 kWh.

The price data tell a different story. Across all customer types, the average price of electricity itself, before network fees and taxes, fell from €129/MWh to €115/MWh in 2025, a decline of 10.68%.

That fall did not translate into lower household bills. The all-in electricity price paid by an average residential customer rose to €266.5/MWh, or 26.65 cents/kWh, an increase of 31.4% from 2024.

The ILR attributed the rise largely to lower state support and higher network fees. Reduced state aid added €77.9/MWh to the price, while network fees added €10.8/MWh.

Gas remains stuck

A separate ILR publication on natural gas underlined the wider limits of Luxembourg’s domestic energy supply. Gas consumption rose 1.54% in 2025 to 6,857 GWh, while imports reached 6,758 GWh, almost exclusively from Belgium.

Gas produced in Luxembourg from biomass and fed into the networks stood at only 44 GWh. Household gas prices also remained far above their pre-energy-crisis level, with the all-in price paid by an average residential customer rising 10.9% to 9.14 cents/kWh in 2025, compared with 5.26 cents/kWh in 2021.