electricity and gas cross-border infrastructure projects commissioned in the EU since 2013.
Energy infrastructure development
2026 Monitoring Report
ACER’s 2026 Monitoring Report on energy infrastructure development in Europe examines whether electricity, gas and hydrogen networks are adapting to changing energy needs, and what this means in terms of investment costs, delays and costs for consumers.
As renewable generation expands and electricity demand grows, driven by heat pumps, electric vehicles and data centres, electricity grids need to accommodate new connections, as well as shifting generation and consumption patterns. Meanwhile, gas networks must adapt to lower demand, and hydrogen is still at an early stage. Developing the right infrastructure, efficiently and on time, will determine whether Europe can meet its decarbonisation goals and keep energy affordable for households and industry.
What trends did ACER monitoring find?
Investment trends differ markedly across electricity, gas and hydrogen networks, reflecting their different roles and levels of maturity.
Electricity grid investment is rising fast. Annual investment in electricity transmission nearly tripled, from €10.4 billion in 2019 to €30.5 billion in 2025.
Cross-border projects are often delayed. On average, 22% of electricity transmission projects of common interest (PCIs) and projects of mutual interest (PMIs) is delayed each year, mainly due to lengthy permitting procedures. A one-year delay can cost around €4 billion in lost economic welfare.
Electricity grid congestion is costly. Growing demand for grid connections is lengthening queues. At the same time, remedial actions taken by transmission system operators (TSOs) to relieve grid congestion cost European consumers €5.4 billion in 2025, over 25% more than in 2024.
Income collected to manage electricity grid congestion is largely set aside for later use. Annual congestion income from day-ahead markets exceeded €9 billion in 2025, seven times the 2019 level. Yet, 60% (about €12.5 billion) of the total congestion income available is set aside by TSOs for later use, rather than reinvested in cross-border grids or directed towards tariff reductions. ENTSO-E’s pan-EU ten-year network development plan (TYNDP) shows no projects under construction in around 40% of EU countries.
Rising electricity network costs weigh on household bills. Electricity network costs for EU households rose by 40% between 2019 and 2025, reaching 84 EUR/MWh. They now account for around 28% of the average household electricity bill.
Gas networks are adapting to lower demand. Gas investments are broadly stable compared to 2019, while demand remains 16% below its 2017-2021 baseline. Average transmission tariffs increased by 40% between gas years 2020/2021 and 2024/2025, highlighting the importance of adapting existing networks to lower demand while keeping costs under control.
Hydrogen networks are at an early stage. EU electrolyser capacity (used to produce hydrogen with electricity) reached 0.49 GW, well below the 30-58 GW target envisaged for 2030 in national strategies and EU scenarios. Network development will need to progress gradually, reflecting the pace of production capacity and demand growth.
ACER’s recommendations
ACER recalls its previous recommendations and actions to:
Make better use of existing networks: strengthening demand response and market-based congestion management, ensuring full implementation of the 70% cross-border capacity requirement, applying cost-reflective network tariffs and deploying grid-enhancing technologies.
Improve infrastructure planning and delivery: promoting transparent, more integrated planning across electricity, gas and hydrogen networks, and supporting timely project delivery through simpler, more predictable permitting procedures.
Address shortcomings in cost-sharing mechanisms: distributing network costs fairly among users over time and reviewing how costs and benefits of cross-border projects are shared between countries.
Looking ahead
ACER will continue to monitor grid planning, project delivery and investment trends.
The next report on energy infrastructure development in Europe will be published in 2028.
Energy infrastructure development
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Highlights
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116
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3 times
more annual electricity transmission investment than in 2019.
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7 times
rise in electricity congestion income since 2019, most of it is not yet activated.
Report
ACER’s 2026 Monitoring Report on energy infrastructure development:
examines investment and progress across electricity, gas and hydrogen networks;
assesses congestion income, project delays and regulatory barriers; and
identifies ways to improve planning, accelerate project delivery and address affordability challenges.
Infographic
Interested in the main highlights of the report?