As of October 1, 2023, regulations allowing the sharing of a connection by multiple generation installations, known as cable pooling, came into effect. It involves utilizing the transmission capacity of existing or new network connections, for example, in the case of an existing wind power plant, to launch a photovoltaic power plant at the same location. In such a case, both the wind and solar farms share the energy infrastructure and use a common connection. This mechanism aims to facilitate the sustainable increase of installed capacity in various renewable energy installations.
Advantages of Cable Pooling:
- Increased connection capabilities;
Cable pooling allows for more efficient use of existing network infrastructure, which can contribute to an increase in the number of renewable energy installations connected to the grid. This makes it possible to counter the stagnation in the growth of installed capacity due to the lack of available connections.
- Optimization of network operation management;
Integration of various renewable energy sources, such as wind and solar, allows for better management of energy flows, which can lead to a reduction in losses resulting from non-market power redispatching. Cable pooling can facilitate the balancing of electrical energy supply and demand, which is crucial for network stability.
- Support for energy storage systems;
Cable pooling can accelerate and streamline the process of connecting energy storage systems, which is important for network stabilization and the integration of renewable energy sources. Energy storage systems play a key role in compensating for the instability of energy production from renewable sources. Energy storage systems compensate for power surpluses generated due to significantly higher installed capacity compared to connection capacity (the ratio of these capacities sometimes reaches 2). During short periods of high energy generation from both types of installed energy sources, energy storage systems can absorb the surplus to avoid exceeding connection capacity and to prevent wasting energy in case of a potential need to shut down part or all of the source. Stored energy can be released when the generated power drops below the connection capacity and during periods of significantly higher energy prices than those occurring during maximum source generation.
- Increase in energy generation from renewable sources during periods of low sunlight;
Thanks to the ability to combine different types of renewable energy installations, including those based on wind energy, it is possible to increase energy generation during periods of low sunlight, allowing for more stable energy supplies.
- Optimization of the use of connection infrastructure and reduction of capital expenditure (CAPEX);
The application of cable pooling allows for a significant reduction in project costs calculated per unit of energy fed into the grid. This means that when building infrastructure for e.g. 1 MW for a photovoltaic farm, the utilization factor of the infrastructure’s capacity will be relatively low. With approximately the same power output infrastructure to the grid, under the current legal situation, we can add a second farm, this time wind-based, and ideally also an energy storage system. In this case, the utilization factor of the infrastructure built for a maximum power of 1 MW will be significantly higher. With similar costs associated with grid connection, we gain the ability to multiply energy production and thus profits from energy sales.
Disadvantages of Cable Pooling:
- The necessity for operators to pay an advance deposit;
Despite the lack of significant increase in connection capacity and minimal connection costs, grid operators may require applicants to pay an advance deposit towards the connection fee.
- The requirement to adapt existing installations to new regulations;
There is a possibility that existing and connected installations will need to be adapted to the requirements of Commission Regulation 2016/631 (“NC RfG”). This may lead to additional costs and technical complications, especially if these installations were designed according to earlier standards.
- Time constraints regarding connection possibilities;
The connection of RES installations within cable pooling is only possible if the first installation was connected or had connection conditions issued after October 1, 2023.
- Lack of transparency in the process of verifying technical connection conditions;
The process of verifying the existence of technical conditions for network connection is not transparent. The non-disclosure of expert reports commissioned by operators to applicants hinders interested parties from assessing and understanding the technical aspects related to network connection.
Information from the President of the Energy Regulatory Office No. 15/2024 dated March 25, 2024.
In the aforementioned information, numerous issues raising doubts in the area of network connections were addressed, particularly concerning the issue of cable pooling.
The President of the Energy Regulatory Office, referring to issues related to cable pooling, pointed out, among other things, that:
the institution of shared connection infrastructure can be applied in situations where the application for connection conditions:
- includes the initial connection to the grid of two or more renewable energy installations;
- is submitted in cases where connection conditions have previously been issued for the “first” renewable energy installation and a connection agreement has been concluded, and the connected entity applies for the connection of a second or subsequent renewable energy installation;
- concerns situations where a renewable energy installation is already connected to the grid, and the connected entity applies for the connection of a second or subsequent renewable energy installation.
This solution can be applied to renewable energy installations that were connected to the grid before October 1, 2023, as well as where connection conditions were issued and a connection agreement was concluded before this date;
- Within the framework of shared connections, systems can be connected both of the same type of energy source (e.g., two photovoltaic systems) and of different types (e.g., wind system, photovoltaic, hydroelectric, or biogas plant);
- If another installation is to be connected to the grid where a renewable energy installation is already connected, the requirements of the NC RfG regulation apply only to the new installation, unless the previous installation was modernized. This means that in shared connections, if the existing installation has not been modernized, the new regulations do not require changes to the existing installation.
The inability to connect energy storage systems within cable pooling prevents the effective utilization of already installed capacities.
In the context of connecting renewable energy source installations to the power grid with a nominal voltage higher than 1 kV, it is possible to connect two or more installations belonging to one or more entities at a single connection point. An exception is made for installations where the connection point to the grid is the end user’s installation.
For all renewable energy source installations connected in the aforementioned manner, uniform connection conditions are issued, and a single grid connection agreement is concluded. Such an agreement specifies the requirements concerning the location and technical parameters of the metering and settlement systems, which enable precise measurement of the amount of electrical energy fed into and drawn from the grid by each connected renewable energy source installation.
In the event that the connection capacity turns out to be lower than the total installed electrical capacity of all connected renewable energy source installations, the connection agreement must include a detailed description of the methods for securing technical capabilities to ensure that the connection capacity is not exceeded. Thus, this agreement serves as a tool not only regulating the connection conditions but also ensuring that the installations will operate in compliance with the technical requirements of the power grid.
An energy storage system can only be part of a renewable energy source installation if it is connected to devices used for electrical energy generation. Conversely, cable pooling is only possible for connecting renewable energy source installations to the grid. An energy storage system that is not part of a renewable energy source installation cannot, therefore, be connected to the grid in a shared connection model.
If you have any questions or concerns regarding the above matter, please do not hesitate to contact our experts:
Piotr Włodawiec: wlodawiec[at]prokurent.com
Łukasz Moczydłowski: moczydlowski [at] prokurent.com
Paweł Wróblewski: 'p.wroblewski [at] elbudbis.pl
Authors:
Piotr Włodawiec – Attorney-at-law / Senior Partner
Łukasz Moczydłowski – Attorney-at-law / Senior Partner
Paweł Wróblewski – CEO ElbudBis
Relkonds
Material prepared in collaboration with:
