European Renewable Energy Integration Blog

Sweden took 65.4 % of its energy from renewable sources in 2025, the highest share in the EU, according to Eurostat’s provisional renewable energy statistics. Belgium, at the other end of the table, took 14.9 %. Both are members of the same single market, both are bound by the Renewable Energy Directive, and the gap between them is more than four to one.

The directive requires the EU as a whole to reach 42.5 % by 2030. The average in 2025 was 26.2 %. How individual countries got to where they are says a good deal about how renewable energy is integrated into a power system, and why the grid, not the generator, is now the harder part.

The leaders: forests, rivers and wind

Behind Sweden come Finland at 53.0 % and Denmark at 48.2 %. What they have in common is less obvious than it looks. Eurostat notes that the largest single renewable source in all three is solid biomass, largely wood and forestry residues burnt for heat and combined heat and power. Sweden adds hydropower and wind, Finland wind and hydro, Denmark wind and biogas.

That matters because heat is the hardest part of the energy mix to decarbonise, and the Nordic countries solved much of it decades ago with district heating networks fed by biomass. Their high scores rest as much on that as on turbines.

Electricity tells a sharper story. Across the EU, renewables supplied 49.9 % of electricity consumption in 2025. Austria led at 90.8 %, mostly from Alpine hydropower, followed by Sweden at 89.2 %, Denmark at 77.7 % and Portugal at 65.6 %. By Eurostat’s 2024 breakdown, wind produced 38.0 % of the EU’s renewable electricity, hydro 26.4 % and solar 23.4 %.

Portugal’s place in that list deserves a second look. Its renewable electricity comes from a mix of wind, hydropower and a fast-growing fleet of solar parks, and it has reached 65.6 % while sitting at the far end of a peninsula that is only thinly connected to the rest of Europe. Almost all of its exchanges pass through Spain, and Spain’s own links to France cross the Pyrenees at a handful of points. That makes the Iberian grid unusually self-reliant: on a sunny spring day it has to absorb its own solar peak, and on a still winter evening it has to cover its own demand, with far less help from neighbours than Denmark or the Netherlands can count on.

The laggards, and their reasons

The lowest overall shares in 2025 were Belgium at 14.9 %, Slovakia at 16.3 % and Ireland at 17.2 %.

Belgium is small, crowded and home to heavy industry around Antwerp, with little room for large solar parks or onshore wind, and its offshore zone in the North Sea is modest. Slovakia draws much of its electricity from nuclear plants, which count as low-carbon but not as renewable. Ireland is the most interesting case: wind is already one of its main sources of electricity, but transport and home heating still run largely on oil and gas, and those pull the overall figure down.

Ireland also shows the grid problem clearly. An island system with a lot of wind needs somewhere to send the surplus and somewhere to draw from on calm days. Until 2025 its only direct links to Great Britain were the East–West Interconnector and, from Northern Ireland, the Moyle Interconnector. Greenlink, 500 MW to Wales, began operating in 2025, and the 700 MW Celtic Interconnector to France is due in 2028. Each one lets Irish wind reach a larger market and lets the island lean on its neighbours when the weather turns.

Where integration really happens: the links

Denmark is the best example of what interconnection makes possible. A country with a very high wind share can only run that way if it can export on windy nights and import on still days. Danish power flows north to Norwegian hydro over Skagerrak, south to Germany, east to Sweden and, since 2019 and 2023, west to the Netherlands over COBRAcable and to Britain over Viking Link. The Norwegian reservoirs act, in effect, as a battery for Danish turbines.

The EU recognises the principle in its interconnection target: by 2030 every country should be able to import at least 15 % of its installed production capacity. On the Commission’s latest count, sixteen member states are already past that line, and nine have not yet reached even the 10 % set for 2020. The thinnest connections sit on the edges of the continent, and for that reason the Pyrenees crossings and the planned Bay of Biscay cable between Spain and France are among the EU’s priority projects.

The three Baltic states took a different step. In February 2025 they disconnected from the Russian-controlled power system and synchronised with continental Europe, a change explained in the site’s guide to Baltic synchronisation. It did not add a single wind turbine, but it gave Estonia, Latvia and Lithuania full access to the balancing resources of the continental grid. For three small systems planning large amounts of onshore and offshore wind, that shared frequency and those shared reserves are worth more than any single new cable.

If you want to see where all these cables run, the map of Europe’s interconnectors shows the major links with their capacity, length and technology, many of them high-voltage direct current.

What decides the next five years

Two things stand out from the table. First, the countries at the top did not get there with electricity alone; heat and biomass count for a great deal. Second, the country with the most weather-dependent power, Denmark, is also the one that leans hardest on its neighbours, while the places at the edge of the grid, from Ireland to the Iberian peninsula, find each extra gigawatt of wind or sun harder to absorb.

Eurostat’s final figures for 2025 will replace the provisional ones within the next few months. By the time the 2026 numbers follow, the Celtic Interconnector should be close to energisation, and Belgium’s artificial island for offshore wind, will have had another year of construction. The distance between 14.9 % and 42.5 % will not close faster than the cables that have to carry it.