3 System Development

The Ten-Year Network Development Plan:
Building Europe’s future power system

The TYNDP is the outcome of a two-year process, starting with the development of scenarios outlining how the European energy system might look in 2030 and 2040.

Imagine and model future electricity and gas systems scenarios

Scenarios are a crucial element of the TYNDP process and a deliverable that can be used for other studies on future aspects of the energy system.

ENTSO-E and ENTSOG published the final Joint Scenario Report for TYNDP 2020 in June 2020. The Report was presented in a public workshop held in July 2020. In November 2020, ENTSO-E and ENTSOG published their draft TYNDP 2022 scenario building storylines1. The draft report consists of the storyline development for two future Paris agreement compliant (COP 21) scenarios (“Global Ambition” and “Distributed Energy”), together with the outline of the upcoming national policy scenario. The proposed COP 21 storylines are defined along a pan-energy approach, relying on a wide range of energy technologies, sources and carriers, and representing a step towards more system integration in the planning phase.

The previous storyline report for TYNDP 2020 was limited to descriptive (qualitative) information only. Due to a lack of quantitative figures, some stakeholders found it challenging to comment on the proposed storylines. Based on this feedback, the draft storyline report for TYNDP 2022 now incorporates quantitative ranges for some of the key storyline parameters, to improve transparency. The proposed high-level drivers outlining the storylines aim to sufficiently differentiate energy systems for the purpose of infrastructure assessment within TYNDP 2022. Table 6 provides an overview of storyline differentiation based on the high-level drivers.

1 The final TYNDP 2022 storylines were published in April 2021.

Key dates & documents

29 Jun 2020: Publication of the final Joint Scenario Report for TYNDP 2020

3 Jul 2020: Public webinar to present the Joint Scenario Report for TYNDP 2020

3 Nov 2020 –15 Dec 2020: Public consultation on the draft TYNDP 2022 storylines

TYNDP 2022 – two top-down scenarios

Global Ambition pictures a pathway to achieving carbon neutrality by 2050 and at least a 55 % emission reduction in 2030, driven by a fast and global move towards the Paris Agreement targets. This translates into the development of a very wide range of technologies (many being centralised) and the use of global energy trade as a tool to accelerate decarbonisation.

Distributed Energy pictures a pathway to achieving EU-27 carbon neutrality by 2050 and at least a 55 % emission reduction in 2030. The scenario is driven by the willingness of society to achieve energy autonomy based on widely available indigenous RES. It translates into both a way-of-life evolution and a strong decentralised drive towards decarbonisation through local initiatives by citizens, communities and businesses, supported by authorities.

 Distributed Energy
Higher European autonomy with renewable and ­decentralised focus
Global Ambition
Global economy with centralised low ­carbon and RES options
Green TransitionAt least –55 %  reduction in 2030, climate neutral in 2050
Driving force of the energy transition Transition initiated on local / national level ­(prosumers)Transition initiated on a European / international level
Aims for EU energy autonomy through maximisation of RES and smart sector integration (P2G/L)High EU RES development supplemented with low carbon energy and imports
Energy intentsityReduced energy demand through circularity and better energy consumption behaviourEnergy demand also declines, but priority is given to ­decarbonisation of energy supply
Digitalisation driven by prosumer and variable RES managementDigitalisation and automation reinforce ­competitiveness
of EU business.
TechnologiesFocus of decentralised technologies
(PV, batteries, etc) and smart charging
Focus on large scale technologies
(offshore wind, large storage)
Focus on electric heat pumps and district heatingFocus on hybrid heating technology
Higher share of EV, with e-liquids and biofuels ­supplementing for heavy transportWide range of technologies across mobility sectors
(electricity, hydrogen and biofuels)
Minimal CCS and nuclearIntegration of nuclear and CCS

Table 6 – Storylines differentiation based on high-level drivers

The Ten-Year Network Development Plan

The TYNDP is a pan-European network development plan, providing a long-term vision of the power system. A legal mandate deliverable (Article 30(1), Regulation 943/2019), published by ENTSO-E every two years, it is the foundation of European grid planning and the basis on which transmission projects may apply for “Projects of Common Interest” (PCI) status. The elaboration of each TYNDP is a two-year process, as described in Figure 4.

Figure 4 – TYNDP two-year process

Each scenario’s impacts on energy markets and networks are analysed with the help of tailored modelling tools. Thanks to the models, ENTSO-E can explore various system needs and the options which address these needs. We can therefore understand, make transparent and better explain which parts of the network infrastructure are fit for purpose and which need to be reinforced or supported by alternative solutions or technologies. The main role of TYNDP is thus to identify where investment in the electricity system would help to release the expected system constraints, and by doing so provide a fit-for-purpose infrastructure. This is done in two stages: performing a system needs analysis that identifies a high level overview of constraint relief options to allow the decarbonisation of the EU power system at the lowest cost, followed by a call for transmission and storage projects (under different stages of development) across Europe, complemented by an analysis of their impacts under different scenarios.

ENTSO-E released the TYNDP 2020 for stakeholder consultation in November 20202, which was held from November 2020 to January 2021. A public webinar took place in December 2020.

The TYNDP 2020 assessed 154 transmission projects, of which were 97 cross-border projects, representing close to 90 GW of additional cross-border transmission capacity and 26 storage projects, representing 485 GWh of storage capacity. System needs amount to a total of 50GW on close to 40 borders in 2030 and 43 additional GW on more than 55 borders in 2040. Addressing system needs is in line with the Green Deal policy objectives, with 110 TWh of curtailed energy and 53 Mtons of CO2 emissions avoided every year until 2040.

2 The draft TYNDP 2020 was submitted to ACER for opinion in February 2021.

Transmission Projects


Transmission Projects


Additional cross-border transmission capacity


Lines and Cables

The TYNDP 2020 assessed 154 transmission projects, of which 97 cross-border projects representing close to 90GW of additional cross-border transmission capacity. Overall, the TYNDP 2020 ­portfolio represents 46,000km of lines or cables.

Storage Projects


Storage Projects


Storage Capacity

26 storage projects, representing 485GWh of storage capacity. That’s 6 more storage projects than in the TYNDP 2018, with for the first time a TYNDP pilot cross-sector (transport) project.


~ 7.3 to 13.2

Socio-economic Welfare

Collectively, TYNDP 2020 projects generate an increase in socio-economic welfare by 7.3 to 13.2 billion euro per year, depending on the scenario considered.



Investments suffering delays



17% of TYNDP transmission investments suffered delays in the past two years, a share similar to that of previous TYNDPs. Of the 44 projects in permitting phase, 39 were already in permitting phase in the TYNDP 2018.

Investing in the TYNDP project portfolio will contribute to the post-pandemic European economic recovery. During the construction and commissioning of the projects, 1.7 Million jobs could be ensured in European Union countries. In addition, infrastructure projects have a positive impact on production, GDP and public administration ­revenues in the European Union.

Figure 5 – TYNDP 2020 facts and figures

A pilot study assessed the projects’ impact in terms of job creation and GDP. Collectively, TYNDP 2020 projects generate an increase in European socioeconomic welfare of 7.3 to 13.2 billion euro per year depending on the future considered, by reducing CO2 emissions and supporting the integration of RES. Investing in the TYNDP project portfolio would represent 1.7 million jobs in the EU, contributing to the post-pandemic European economic recovery.

Key dates & documents

6 Nov 2020: Release of the TYNDP 2020 for consultation

6 Nov 2020 – 4 Jan 2021: Public consultation on the TYNDP 2020

4 Dec 2020: Public webinar on the TYNDP 2020

A common element of all future energy scenarios is that electricity will become the leading energy carrier (up to 65 %) and that the European electricity grid will be the backbone of the decarbonisation of all energy sectors. That is why infrastructure planning for the future power system will require a multi-sectorial approach. In line with the new “Multi-Sectorial Planning Support” concept, TYNDP 2020 highlighted the need for the energy system to be more integrated and dynamic between all the value chains, linking the specific energy resources to the end-sectors. The various energy carriers (electricity, heat & cooling, solid, liquid and gas fuels) will be linked and converted to provide the most efficient and carbon neutral services. This will facilitate the full decarbonisation while ensuring security of supply and limiting the costs of the energy transition.3

3 In October 2020, ENTSO-E conveyed its key messages on infrastructure development and sector integration at the Energy Infrastructure Forum ­(“Copenhagen Forum”) and at the European Gas Regulatory Forum (“Madrid Forum”).

Key dates & documents

16 Jul 2020: Publication of the ENTSO-E Roadmap for a Multi-Sectorial Planning Support

The cost–benefit analysis methodology

The assessment of infrastructure and storage projects performed in the TYNDP uses a cost-benefit analysis (CBA) methodology drafted by ENTSO-E, in consultation with stakeholders. The methodology is proposed to ACER and the European Commission for, respectively, an opinion as well as further recommendations and a final decision. The CBA results are also used as the basis of the PCI selection process by policy makers. The main objective of the CBA methodology is to provide a common basis for the assessment of projects with regard to their value for European society, in line with Europe’s energy goals.

ENTSO-E developed a third version of the CBA methodology, which improves on the previous versions in its consideration of security of supply, socioeconomic welfare and storage. The draft CBA 3.0 was submitted to ACER for opinion in February 2020.4

4 The draft CBA 3.0 was submitted to EC for approval in March 2021. These developments are outside the scope of this Report and will be covered in the Annual Report 2021, to be drafted next year.

Key dates & documents

11 Feb 2020: Submission to ACER of the draft 3rd CBA methodology

Ensuring resource adequacy

“Resource adequacy” can be defined as the continuous balance, including storage and demand side response, between supply on the one hand and demand levels on the other.

Due to the increasing level of variable RES in the European power system and the associated challenges for system development and operation, a pan-European analysis of resource adequacy has become ever more important. Cooperation across Europe is necessary to accelerate the development of common methodological standards, i. e. a common “language” is required to perform these studies. Resource adequacy requires advanced methodologies to capture and analyse rare events with adverse consequences for the supply of electric power.

Figure 6 – Resource Adequacy

The Mid-term Adequacy Forecast

To account for a growing number of disruption risks related to the evolution of the energy mix – the growing development of RES, reduction of conventional power plants – Europe requires a regular assessment of the adequacy situation, at time horizons of up to ten years ahead. The “Mid-term Adequacy Forecast” (MAF) aims to provide a pan-European adequacy assessment of the risks to security of supply and the need for flexibility for the coming decade. The MAF is based upon state-of-the-art probabilistic analysis, conducted using sophisticated market modelling tools.

It contributes to the harmonisation of resource adequacy methodologies across Europe by being a reference study for European TSOs. The MAF aims to provide stakeholders with the data necessary to make informed, quality decisions and promote the development of the European power system in a reliable, sustainable and connected manner.

In the MAF 2020, published in November 2020, the assessment was carried out for two target years (TY): 2025 and 2030. TY 2025 represents a pivotal year for evaluating adequacy due to expected reductions in coal and nuclear capacity in Europe and enables a comparison with the MAF 2019. TY 2030 was chosen to allow for the evaluation of the adequacy situation further ahead, at the end of the 10-year time horizon. The results indicate mostly low risks of inadequacy in the system for both target years, with a positive evolution in some zones from TY 2025 to TY 2030. However, some countries do show high risks of inadequacy. The zones with the largest risks of inadequacy in TY 2025 are Malta, Sardinia, Turkey and Ireland.

Key dates & documents

30 Nov 2020: Publication of the MAF 2020

Resource adequacy and the Clean Energy Package

The CEP places resource adequacy in a central position in the European energy policy context. It extends the scope of the ENTSO-E MAF and develops it further into a new Pan-European Resource Adequacy Assessment. As provided for by Article 23 of the Electricity Regulation, ACER approved in October 2020 a methodology for a European Resource Adequacy Assessment (ERAA) and a methodology for calculating the Value of Lost Load (VoLL), the Cost of New Entry (CONE) and the Reliability Standard. The stepwise implementation of the ERAA will begin in 2021; the MAF 2020 is thus the last MAF report anterior to the ERAA implementation.

Key dates & documents

2 Oct 2020: ACER approval of the methodology for a European resource adequacy assessment (subject to the amendments as set out in Annex I to Decision 24/2020)

5 Dec 2019 – 30 Jan 2020: Public consultation on a European resource adequacy assessment

2 Oct 2020: ACER approval of the methodology for calculating the VoLL, the CONE and the Reliability Standard (subject to the amendments as set out in Annex I to Decision 23/2020)

5 Dec 2019 – 30 Jan 2020: Public consultation on the the methodology for calculating the VoLL, the CONE and the Reliability Standard

The Seasonal Outlooks

ENTSO-E’s Seasonal Outlooks (Article 30(1)f, Regulation 943/2019) are pan-European, system-wide analyses of risks to electricity security of supply. Analyses are performed twice a year to ensure a good view regarding the summer and winter and to present TSOs’ views on the risks to security of supply and the countermeasures they plan for the coming season, either individually or in cooperation. Each outlook is accompanied by a review of what occurred during the previous season.

The outlooks are performed based on the data collected from TSOs and using a common methodology. Moreover, ENTSO-E uses a common database in its assessment, the Pan-European Climate Database (PECD), to determine the levels of solar and wind generation at a specific date and time. ENTSO-E analyses the effect on system adequacy of climate conditions, evolution of demand, demand management, evolution of generation capacities, and planned and forced outages.

Key dates & documents

15 June 2020: Publication of the Summer Outlook 2020

17 June 2020: Summer Outlook 2020 Webinar

30 November 2020: Publication of the Winter Outlook 2020

1 December 2020: Winter Outlook 2020 Webinar

ENTSO-E published the Summer Outlook 2020 in June 2020 and the Winter Outlook 2020/2021 in November 2020.

Since 2020, and in line with the CEP, ENTSO-E has applied a probabilistic approach to its seasonal adequacy assessments – using a set of possible scenarios for each variable which enables it to detect more risks. This is in line with the methodology used in the MAF.

Moreover, to improve the coordination with the week-ahead adequacy assessment performed by RSCs, ENTSO-E submitted in January 2020 a proposal for a methodology for assessing seasonal and short-term adequacy, namely monthly, week-ahead to at least day-ahead adequacy (Art. 8 of the Risk Preparedness Regulation 2019/941). ENTSO-E also submitted in January 2020 a proposal for the methodology for identifying regional electricity crisis scenarios (Art. 5 of the Risk Preparedness Regulation). ACER approved both risk preparedness methodologies in March 2020.

Connection codes: Integrating renewables

The objectives of the three Connection Network Codes (CNCs) – Demand Connection Code (DCC), Requirements for Generators (RfG), and High Voltage Direct Current Connections (HVDC) – are to ensure the integration of decentralised RES and the increased demand response into the power system while simultaneously maintaining security of supply and resilience at all times, and to facilitate the internal electricity market by levelling the playing field of grid users in different member states.

Key dates & documents

2 Dec 2020 –31 Jan 2021: Public consultation on several revised IGDs

The implementation of connection codes is the responsibility of each EU member state. In this context, ENTSO-E acts as a platform to maintain and eventually amend CNCs; share information, guidance and best practices for national implementation processes; and monitor their progress, especially through the development and delivery of non-binding written guidance – Implementation Guidance Documents (IGDs) – to its members and other system operators.

The development of IGDs is fuelled by discussions with stakeholders from the drafting phase onward, via dedicated expert groups and the Grid Connection Stakeholder Committee. In December 2020, ENTSO-E launched a consultation on the revision of several IGDs.5

5 These IGDs were revised and published in June 2021. These developments are outside the scope of this Report and will be covered in the Annual Report 2021, to be drafted next year.

Implementation monitoring

ENTSO-E monitors the implementation activities in each country via its Active library, looking in particular at divergences in national implementation. The “Monitoring report on Connection Network Codes Implementation” was published in December 2020.

In accordance with Art. 59(2) RfG and 76(2) HVDC, ENTSO-E shall provide ACER with the information required to monitor the implementation of these two network codes. In response to ACER’s requests, ENTSO-E maintains summary tables for each Member State, clarifying the type of information that need to be collected by the TSOs and DSOs. The information will then be aggregated and submitted to ACER by 30 June each year.

Key dates & documents
Long term planning and resource adequacy assessments provide mid-term monitoring as well as long term visions to achieve a carbon-neutral European energy system by 2050. This aims to support strategic orientations by authorities and investment decisions by various actors of the electricity market.


ENTSO-E Annual Report 2020

This Annual Report covers the period from January to December 2020. It focuses on the legal mandates given to ENTSO-E. The activities covered in this report were performed thanks to the 42 members of ENTSO-E who provide its financial resources and whose staff provides expertise to the Association.


  1. System Operation
  2. Market
  3. System Development
  4. Transparency Regulation
  5. Research, Development and Innovation
  6. Cybersecurity, Interoperability and Data
  7. TSO–DSO partnership and demand side flexibility
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