The 2025 Development Plan was submitted to the Ministry of the Environment and Energy Security on 27 January 2025, following its approval by Terna’s Board of Directors on 21 January, in line with the requirements of Legislative Decree 93/11, as amended by Law 120/2020³⁰.

The new 2025 Plan, following on from the previous 2023 edition, for which ARERA expressed a favourable opinion in Opinion 4/2025/I/eel of 14 January 2025, consolidates Terna’s role at the service of the country for a decarbonised and sustainable future.

In fact, Terna plays a central role in the energy transition process, both as an enabler of a system increasingly based on renewable sources and as a strategic leader in this great process. In fact, to achieve the global goal of decarbonisation the electricity grid is the main enabling factor, to which are also added a number of fundamental issues linked precisely to the complexity of the current context.

To this end essential measures are planned for the pursuit of the national and European objectives of energy transition, independence, resilience and efficiency of the electricity system, in continuity with the previous edition of the 2023 Plan.

The Plan is consistent with the 2024 PNIEC, with the updated Terna-Snam scenarios (2024 Scenario Description Document) and with the decarbonisation objectives, which impose new challenges on the electricity sector in line with the forecast of trends in energy needs and demand to be met.

Installed solar and wind power capacity is expected to increase by more than 65 GW by 2030 compared to installed capacity in 2023, and more than 94 GW by 2035.

Given the complex and challenging electrical environment, the most useful and urgent works were planned according to an electrical priority, while seeking innovative low-capital-intensive solutions to reduce costs and maximise investment effectiveness.

The 2025 Development Plan envisages an investment programme of more than €23 billion over the ten-year horizon covering the years 2025-2034 (up 10% compared to the previous ten-year Plan), with an overall value beyond the 10 year horizon of up to approximately €40 billion, with the aim of enabling the energy transition and achieving the environmental objectives outlined by EU regulations in both the medium and long term.

Given the challenges faced by the electricity system as a result of the trends identified in the projected energy scenarios and ongoing climate change, planning the development of the transmission grid must meet the following electricity system objectives:

Below are the main figures of the 2025 Development Plan and the expected benefits from the achievement of these objectives:

The 2025 Development Plan responds to the country’s infrastructure needs, seeking to define development priorities, i.e. those projects that offer the greatest value for the system, facilitating the investments required for the energy transition. The investments envisaged in the 2025 Development Plan to enable the achievement of system benefits are grouped into the following main categories: NON-RES Connections, RES Connections, Large HVDC and Hypergrid Projects, Interconnections, VHV projects.

These projects serve four main purposes:
• Develop enabling and innovative infrastructure to achieve the efficient target capacity to increase transit limits between market sections and maximise energy exchange;

• Resolve local congestion, ensuring safe operation within market areas through intra-zonal planning;

• Ensure the security of electricity systems and the integration of markets through interconnections, which allow flexible and balanced management of energy resources, facilitating exchanges between national grids;

• Manage the huge demand for connecting renewables through innovative solutions such as the definition of a new model – Efficient Regional Planning – with the aim of ensuring efficiency in the implementation of grid works enabling the integration of new resources.

With regard to the last need illustrated above, the handling of a large number of connection requests, which have increased more and more in recent years, has caused administrative congestion and authorisation difficulties, as well as higher infrastructure costs due to the potential redundancy of grid works. The magnitude of the phenomenon calls for new variables to be considered in grid management in view of Terna’s regulatory obligation to connect all those who so request to the National Transmission Grid (NTG).

This was the reason for the introduction of the aforementioned new model of Efficient Regional Planning, adopted by Terna to ensure efficiency in the construction of works enabling the connection of new resources, minimising costs for the system and the impact of infrastructure on the local region.

Terna has defined a new process for integrated territorial and environmental planning and efficient grid infrastructure planning. This approach will bring benefits in terms of speeding up the authorisation of works and accelerating the commissioning of new plants, taking into account the smaller grid developments required. This will also lead to a reduction in complexity due to the simplification of the dynamics of the technical meetings, a reduction in overall system costs and a lower local impact of grid works.