Licensing of storage facilities

In addition to laying down technical rules that storage facilities must comply with, as well as making them subject to the provision of system services, this Order addresses the main difficulty in implementing storage facilities - the allocation of injection capacity in the Public Grid- by ruling both the alteration (conversion) of a solar photovoltaic power plants into autonomous storage and the use of the grid injection capacity already awarded to power plants.

The Order comes into force on February 11, 2025.

Technical Conditions

Storage facilities to be licensed under the terms of the Order must ensure compliance with the requirements applicable to the generator modules as established in Commission Regulation (EU) 2016/631 of April 14, 2016 and in Ministerial Order no. 73/2020 of March 16, considering the injection capacity and not the charging capacity.

For the purpose of categorizing Types A, B, C and D under the aforementioned legislation, the capacity will be set as the maximum value between (i) the injection capacity of the storage facility or (ii) the injection capacity of the power plant with which it combines.

The Order provides that the Grid Operator and the SEN Global Manager ("GGS") may request the use of the storage system to the maximum of its technical possibilities, which may not be refused by the holder of the storage facility, unless there is a duly justified overriding reason.

Therefore, the installation must be equipped with systems that allow access to the GGS in real time and integration of its computer systems into a GGS Control Center.

System Services

As the public consultation on changes to the Global System Management Procedures Manual is ongoing, the Order determines that it is mandatory for storage facilities to participate in mechanisms for resolving technical restrictions and in the markets, to ensure a balance between generation and consumption, including:

• Replacement reserve or equivalent;
• Frequency restoration reserve(s) with manual activation or similar;
• Frequency restoration reserve(s) with automatic activation or similar.

On the other hand, the storage facility must also ensure voltage and reactive control services to the SEN, as well as providing the primary reserve service or equivalent.

In the case of connections to the distribution network, the reactive power management service is the subject of an agreement between the storage holder and the Distribution Grid Operator.

Change of power plant technology

The license application must be submitted to the DGEG by the title of grid injection capacity (“TRC”) holder, together with, among other things, the existing TRC, a summary of the intended operating conditions, the maximum injection power into the Public Grid, and the maximum apparent power value for charging from the Public Grid.

In cases where the TRC concerns a project that has already been licensed, the sponsor shall duly justify the impossibility of building the originally licensed power plant for reasons beyond the control of the holder of the production license, with supporting documentation.

The alteration procedure is subject to the opinion of the competent grid operator and the GGS, which will verify the maximum value of the apparent loading power of the storage facility from the Public Grid and any operating restrictions.

The submission of this request for a change of technology does not preclude the future addition of an power plant to the autonomous storage facility, i.e. an hybridization in the “opposite direction” to the usual one.

The question remains as to whether the same change is possible for power plants subject to prior registers and not to a TRC / production license.

Stand-alone or collocated storage

If a storage facility wishes to connect directly to the Public Grid or to the internal grid of the pre-existing power plant or to the UPAC through reserved injection capacity in the Public Grid already awarded to a power plant, it may do so provided that it:

• connects to the same interconnection point, in the case of installations connected to the National Transmission Grid;
• connects to the same circuit, in the case of installations connected to the National Distribution Network.

The application of this regime to autonomous storage is unclear, since by definition it is not associated with a power plant or UPAC. In this sense, it seems that the reference to autonomous storage should be understood not in the sense of sharing the injection capacity of a power plant (i.e., hybridization) but in the sense of sharing the connection infrastructure to the Public Grid by generation and/or storage facilities which were awarded with injection capacity separately.

The request for a storage facility must be submitted with, among others:

• The elements for the request of production license set forth in Annex I of Decree-Law no. 15/2022
• Summary of the operating conditions for the storage facility, in particular the maximum powers for injection into the Public Grid and for charging from the Public Grid,
• Clear identification of the coordinating power plant(s)
• In the event of legal separation, a written agreement between the holder of the storage facility and the holder of the collocated power plant, which shall also state that the power plant will not be coordinated with other autonomous storage facilities.

The procedure is subject to the opinion of the competent grid operator and the GGS, which will verify the maximum value of the apparent loading power of the storage facility from the Public Grid and any operating restrictions.

If the promoter has not provided the security deposit (EUR 10,000 per MVA), as well as the compensation to the SEN (EUR 1,500 per MVA) within the scope of the request to obtain a capacity reservation, it must do so in this procedure.

The holder of the storage facility must ensure during operation that the power plant or power plants with which it is coordinated will not be coordinated with other autonomous storage facilities.

In order to ensure that the total injection power into the Public Grid does not exceed, at any time, the aggregate value of the capacity reserves set out in the TRCs or pre-existing registrations, the Grid Operator and the GGS may request additional connection requirements (e.g. systems that guarantee the simultaneous non-injection of installations beyond the capacity allocated to the set).