The rules according to which electrical energy is sharing among the members of a Sharing group are determined by sharing keys.
As part of the agreement with the grid operator, you define rules to determine how the electricity produced is being shared within an AC or a CE.
There are several possibilities:
- Priority means that the electricity produced is distributed among the members of the Sharing group according to a predefined order.
- Percentage means that a household always receives the same share of available electricity.
- Pro rata means that the electricity is shared between the members of the AC or CE according to their present consumption.
The Sharing group can also decide to share the electricity according to specific sharing rules, which must then be defined in the agreement with the grid operator.
The rules can be changed at any time.
As soon as a POD is attached to a Sharing group, the grid operator determines, from the original metering values and the sharing keys, the “Quarter-hourly energy balances”, i.e. the metering values that result for each of the PODs after sharing.
Thanks to the smart electricity meters installed in each household, the electrical energy consumed or produced is measured every quarter of an hour. The calculation of the electricity to be shared is therefore based on these quarter-hourly values.
As a result, it may happen that in a quarter of an hour, a POD receives all of its electricity from the Sharing group to which it belongs, and that in the following quarter of an hour, this same POD receives electricity from the grid to meet its needs. It may also happen that a POD of a production plant shares at a given moment all of its available energy with the members of its Sharing group and injects electrical energy into the grid shortly afterwards.
Therefore, each consumption POD is always supplied with energy, either by the Sharing group or via the grid. Similarly, the electricity produced in a Sharing group is either shared with the members of the Sharing group or injected into the grid. No energy gets lost.
The rules, according to which the electrical energy is shared between the members of a Sharing group, are determined by sharing keys.
A series of quarter-hour values, measured over a longer period of time (day, month, year), is called a “load curve”.
On the one hand, the load curve of the original values that were measured on a POD (whether it is a withdrawal point or an injection point) is therefore called the “original load curve”. On the other hand, the load curve that is associated with this same POD after taking into account the sharing keys and the available or shared energy is called the “Energy balance”.
Energy balances are calculated for each quarter hour on the basis of so-called “static and simple” sharing keys. This means that energy sharing within a Sharing group is not done on the basis of monthly or annual cumulative values, but that the energy to be shared is calculated individually by the grid operator for each quarter hour and for each POD.
- The energy produced by a production plant is usually shared with individual withdrawal points, based on the present energy needs of the consumers. The more energy a withdrawal POD in a Sharing group needs at a given time, the more energy it receives proportionally from the Sharing group’s production plant. This form of calculation is known as “Pro rata“.
- If a POD is to be treated preferentially in the distribution of energy within a Sharing group, it can be assigned a “Priority“. A withdrawal POD is thus supplied with electrical energy before the other withdrawal points of the same Sharing group. If a specific production plant has priority over other production plants within the same Sharing group, the consumers of this Sharing group are first supplied with the electrical energy produced by the priority plant before the energy of the other production plants is shared with the members of the Sharing group. The use of the Priority key is optional for all withdrawal PODs and for all injection PODs.
- As an alternative to Priority, a withdrawal POD can be assigned a “Percentage“. In this case, the consumer receives a certain percentage of the electrical energy available in the Sharing group at that moment. The sum of all percentages must not exceed 100, because it is not possible to share more energy between consumers than that provided by the production plants assigned to this Sharing group. While the use of the percentage key is optionally possible for withdrawal PODs, it is not possible to assign a percentage to an injection POD.
CONSOMMATEURS
| POD | Priorité | % | Prorata |
| LUxxxx1 | 1 | |  |
| LUxxxx2 | | 50 |  |
| LUxxxx2 | | 20 | |
PRODUCTEURS
| POD | Priorité |
| LUxxxx4 | |
| LUxxxx5 | 1 |
| LUxxxx6 | |
The grid operator provides a model agreement for an AC and another for an EC, both of which have been approved by the Institut Luxembourgeois de Régulation. If the members of a Sharing group communicate their corresponding sharing keys to the grid operator through their appropriate agreement, the grid operator proceeds to the (automated) calculation of the resulting Energy balances and transmits them to the representative of the Sharing group.
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However, a Sharing group is not obliged to use the standard keys described above. Instead, each AC and each CE have the possibility to define their own rules, according to which the sharing of electrical energy within the Sharing group applies. In this case, it is up to the Sharing group to establish the Energy balances of each POD and to provide the grid operator with the corresponding quarter-hourly values, so that the grid operator can verify these values and transmit them to the respective suppliers for each POD accordingly.
