Photovoltaic: What plant operators need to know about the new power plant controller requirement

On 1 December, new rules for the connection of electricity generators to the medium-voltage grid come into force in Italy. This affects all photovoltaic systems larger than 1 MW. For these photovoltaic systems, a compliant power plant controller must be installed. In this article, you will learn what you as an operator must consider and what requirements are placed on a plant controller beyond feed-in management. You will also gain an insight into how manufacturers adapt their plant controllers to the norm from product manager Christoph Fröhlich, who manages this process at the German manufacturer meteocontrol.

What is the new obligation about?

Power plant controllers regulate and monitor the grid feed-in of renewable energies, thereby contributing to the stability of the electricity grid. Plant controllers can either receive and implement commands from the grid operator or autonomously control the feed-in of active and reactive power depending on local grid parameters. If the grid is overloaded, the feed-in power can be limited if necessary. The European Union had already decreed the definition of a grid code with grid connection requirements necessary for this in 2016 (2016/631). The EU regulation is gradually being implemented country by country.

The Italian norm sets high requirements

Christoph Fröhlich from meteocontrol knows first-hand how the adaptation of power plant controllers to new norms works. The German manufacturer of PV monitoring and control systems has been present in Italy since 2011 with its subsidiary in Milan. The product manager explains: "We are currently working at full speed for our Italian customers on the conformity of our power plant controller blue'Log XC. For Germany, it has already been certified since 2019 according to VDE-AR-N 4110 and 4120, where the requirements are also high."

The updated Italian norm CEI 0-16 from the Italian Electrotechnical Committee defines on 666 pages together with ARERA resolution 540/2021 the requirements and responsibilities for connecting power generators to the medium-voltage grid. Certification in Italy is challenging: "The German certificate cannot be reproduced 1:1 for Italy. You don't go to the certification body and simply have the document issued for another country. The requirements are very different," says Fröhlich. In many countries there are only general requirements for generation plants. In Italy, on the other hand, an entire annex to the standard is dedicated to the power plant controller. This requires more extensive software adaptations.

For example, control parameters are not only configured locally in the plant controller but must also be able to be specified remotely by the grid operator via the IEC 61850 protocol. In addition, the Italian standard attaches great importance to cyber security. To meet this need, certified product development processes in the company (IEC 62443-4-1) are required on the one hand and extensive hardware and software functions on the product itself (IEC 62443-4-2) on the other. In addition, a cryptographic module must be available for authentication so that cryptographic keys can be stored in the controller. Accordingly, all manufacturers need to invest significantly in the technical development of the hardware and software.

In order to be compliant, various certificates must be available. The electromagnetic compatibility and the required control functions must be tested by accredited institutes. As proof, the test reports must be kept by the manufacturer for 20 years. On this basis, the power plant controller manufacturers then formulate a kind of self-declaration "manufacturer's declaration", with which they confirm that they are compliant with the CEI 0-16 standard. meteocontrol itself is already in contact with customers and is planning to deliver a compliant comprehensive solution and services in spring.

What PV operators need to consider

The new Italian grid connection requirements have been defined in the updated norm CEI 0-16. You may have already received mail from your grid operator about this: All power generation plants from 1 MW upwards must install a norm compliant power plant controller. A distinction is made between existing plants (commissioned by 30 November 2022) and new plants commissioned after 1 December 2022. For existing systems, it is sufficient if the controller is retrofitted by 31 January 2024. When planning new installations with commissioning after 1 December, the power plant controller must be considered from the start.

The installation or retrofitting of power plant controllers is financially rewarded. If the installation is reported between 1 December 2022 and 31 March 2023, the reward is 10,000 euros, up to 30 June 2023 it is 7,500 euros and up to 30 September 2023 it is still 5,000 euros. Those who manage to install it by 31 January 2024 receive 2,500 euros.

As soon as a compliant power plant controller has been installed, this should be reported to the grid operator using a sample form. The amount of the subsidy depends on the date of receipt of this declaration by the grid operator. The grid operator then has two months to check the conformity of your installation and will then reply in writing.

With the favourable expansion dynamics of renewable energies, the need for action to keep the electricity grid stable is increasing. Therefore, clear standards and also high requirements for feed-in management and cybersecurity are important. Christoph Fröhlich assumes: "The emerging standard is not only relevant for Italy. We assume that similar elements of the norm will be required in other countries in the next few years."

In Italy, the expansion of photovoltaics almost tripled in the first three quarters of this year compared to the previous year. This upward trend is attributed in particular to simplified approval processes.

>> Read more about the CEI 0-16 regulation for the Italian electricity market and meteocontrol´s turnkey solution