Hungary’s first industrial solar power plant whose production can be automatically fine-tuned according to current demand has been commissioned.
More and more industrial companies in Hungary are taking significant steps to make their energy consumption greener. However, it can be challenging for them to integrate weather-dependent solar power plants into their systems cost-effectively. At present, industrial end users are not allowed to feed energy generated by their solar power plants but not used on site back into the Hungarian public grid. Therefore, these systems designed to reduce self-consumption must be equipped with mandatory reverse power protection and anti-islanding protection.
Industrial companies can secure predictable green energy with intelligent control
For both types of protection, established technical solutions have developed for smaller power plants. For reverse power protection, data loggers are most commonly used on the inverters that convert direct current into alternating current, supplemented by a consumption meter. In the case of anti-islanding protection, a dedicated protection device generally monitors the presence of grid voltage and, if it disappears due to a system fault, switches off the power plant. However, in larger power plants, implementing systems similar to those described above can encounter difficulties. For example, numerous data loggers would have to be used, electricity consumption and energy generation may take place at different voltage levels, and simply due to the size of the power plant, the distance between the location of detection and intervention may extend to several kilometers.
Siemens now offers an alternative for these protection and control challenges, as well as for the supervision of large power plants: with its new software-based solar power plant control solution, it combines substation data collection with modern substation protocols.
This intelligent, automated system therefore primarily handles reverse power protection challenges through control, acting on up to several hundred inverters. At the same time, it also serves as the intervention device for reverse power protection within the communication network. The solution provides complex supervision at field level by collecting information available from the energy distribution devices of the power plant sections and from its inverters. In addition, it transmits the necessary data from the field level to cloud-based aggregator monitoring systems, thereby enabling the establishment of remote power plant and energy distribution supervision, even for several power plants.
The system can provide a solution for sites that want to combine several types of renewable energy generation equipment, for example with wind power integration, and it is also capable of managing energy storage systems alongside solar power plant inverters and wind turbines.
Such control aimed at reducing self-consumption had not previously been implemented in a large-scale industrial environment in Hungary.
First in Hungary
This complex control solution was first applied at the Környe site of AGC Glass Hungary Kft., which manufactures rear and side automotive glass for the automotive industry, at a solar power plant covering an area of 5 hectares and comprising nearly 9,000 solar panels. The investment, capable of 4.002 MWp DC output and providing annual energy production of 4.8 GWh, could cover the annual energy consumption of approximately 1,900 households. The design, construction and operation of the solar power plant were carried out by E.ON Energiatermelő Kft., which selected Siemens Zrt. as a partner for developing the solution already during the planning phase.
The 34 100 kVA inverters responsible for receiving solar energy and converting direct current into alternating current are monitored and controlled by Siemens’ SICAM Photovoltaic Plant Control application, developed for the integration and intelligent automation of renewable energy sources. In addition to real-time control, the software also performs power plant monitoring functions, for example monitoring electricity generation with the help of sensors measuring temperature, wind speed, humidity and solar irradiation.
The system, commissioned at the end of 2023, transmits the collected data to the cloud infrastructure operated by E.ON, through which the production of the solar park can also be controlled remotely, and the amount of electricity planned to be generated can be forecast and scheduled. Since components of the solar system supplied by an external manufacturer were also integrated into Siemens’ control, data collection and monitoring system, the entire power plant can be managed as a single unit.
Towards microgrid networks
The investment may also serve as a model for the installation of domestic microgrid networks.
Microgrids, as intelligent local energy distribution systems partly independent of the public electricity grid, integrate the electricity generation, consumption and storage equipment connected to them into a single unit. By transmitting real-time data from IoT-compatible low- and medium-voltage devices, they can also communicate with cloud-based systems, which can then optimize and automatically regulate energy management, including through the use of artificial intelligence, while continuously responding to current changes.
The use of such a microgrid network has, for example, made Siemens’ headquarters in Vienna and Munich even more sustainable.