Connection Codes

Ensuring system security and sound technical evolution

​​​​​Network codes and guidelines are binding rules governing connection requirements to the electricity networks in an effective and transparent manner. They were established in 2009 by the EU Regulation on conditions for access to the network for cross-border exchanges in electricity  and recast in 2019 by the Regulation on the internal market for electricity.

The codes are crucial for ensuring the safety of system operation and the efficiency of the European Union's power grid. ​​

Grid Connection Codes

​​Grid connection refers to all the subjects establishing and maintaining a physical connection between the transmission and/or distribution grids and the grid users.  

Grid connection, or network connection, is one of the areas regulated by the specific network codes. These rules aim to develop a harmonised electricity grid connection regime, as well as efficient and secure operations. This is particularly important in view of the integration of an increasing share of sources of renewable energy in the system. European rules on grid connection also ensure a fair competition in the electricity market, and facilitate the electricity trade across the Union.

Three network codes on grid connection have been developed:

  • The network code on requirements for grid connection of generators (RfG Regulation) establishes common standards that generators must respect to connect to the grid.

  • The network code on demand connection (DCC Regulation) sets up harmonised requirements that demand facilities must respect to connect to the grid. 

  • The network code on requirements for grid connection of high voltage direct current systems (HVDC Regulation) covers the definition of harmonised standards for direct current (DC) connections.​​​

Amendment to the Grid Connection Codes

The European Commission invited ACER to initiate the process to amend the existing EU network codes. ACER published a draft Policy Paper in May 2022 and gathered initial feedback from stakeholders during a public workshop and a public consultation in June 2022 (access the responses of the June 2022 public consultation in the Evaluation of Responses Report). ACER is running a full-fledged public consultation from 26 September until 21 November 2022.

The aim is to update the network codes to further support the EU power grid embracing emerging developments such as e-mobility, storage and energy communities.

Policy Paper on the amendments to the grid connection network codes

In its Policy Paper published in September, ACER provided a high-level outline of the main areas  to improve the Network Code on Requirements for Grid Connection of Generators and the Network Code on Demand Connection.

The ACER Policy Paper on Grid Connection Network Codes reflects ACER’s considerations on possible amendments to the grid connection network codes following input received from stakeholders during the summer 2022.

The Policy Paper addresses potential amendments to the European network codes concerning among others:

  • technical requirements for storage, mobile storage (e.g., electric vehicles) and electrical charging points;
  • requirements for mixed customer sites (MCSs), active customers and energy communities;
  • significant modernisation of system users’ facilities and equipment;
  • advanced capabilities for grids with significant distributed energy resources (DER) and converter-based technologies; and
  • criteria to determine generators significant for the system

Next steps

Following the full-fledged public consultation, ACER will evaluate stakeholders’ wording proposals for amendments. Motivated submissions are to inform ACER’s own proposals for network codes amendments that will be drafted in Q1 2023. Subsequently, ACER will publicly consult its amendment proposals in Q2 2023.

ACER plans to submit to the European Commission its proposed amendments to the grid connection network codes by the end of 2023.

Timeline of the process to amend the existing EU network codes

Access the Policy Paper.

Access the Public Consultation.

Access the Public Workshop and the presentations.