Netting calculations

Accounting point energy netting refers to the netting of metering data from related consumption and (small-scale) production accounting points within a time step (15 minutes). In this case, the difference between consumption and production (more precisely, its absolute value) is recorded for either consumption or production, whichever is greater. Reactive energy is not netted.

Datahub performs a netting calculation in connection with the DSO’s metering data message when the metering data necessary for calculating the results of the netted accounting point pair has been delivered to Datahub. At the end of the calculation, Datahub delivers the calculation results to all parties that have the rights to receive them.

The table below shows an example of netting for the first four hours of the day.

Netting calculation principles

The netting calculation is based on the related accounting point information and the maximum power information of the production device of the small-scale production accounting point in Datahub. The netting calculation is performed whenever the related accounting point information is valid, the production accounting point has one or more production devices, and the total sum of the maximum power of the production devices does not exceed 100 kVA (if the conditions for the netting calculation are met, the information ‘Is netting applied’ is stored for the accounting point). If the production device is not reported or the maximum power exceeds 100 kVA or the production device does not have maximum power information, the accounting point is left out of netting calculations.

The maximum power of the production device of a small-scale production accounting point is converted from the units W, kW, MW, GW reported in the Datahub processing directly to VA, kVA, MVA, GVA. If the DSO is aware of cases where the conversion is not directly available, the DSO must update the power information so that the maximum capacity is correct after the conversion. If the maximum power of the production device changes so that the accounting point should either be included in or removed from the netting calculations, the DSO must first remove the related accounting point information from Datahub, then update the production device information and then add the relation again. This way the changes related to the calculations enter into force.

The execution of the calculation does not depend on other information, such as the state of the accounting point or its agreements. If one of the related accounting points has status ‘under construction’, no metering data is expected for that accounting point. In this case, Datahub provides the necessary readings (zero/OK) for the accounting point under construction, and the calculation is performed for both metering points. If both accounting points are under construction, the calculation is not performed.

The time step of the netting calculation results depends on the time step used in the balance settlement. Balance settlement was performed on an hourly basis until May 2023, after which it transitioned to a 15-minute time step. During hourly balance settlement, netting was calculated according to the metering point’s time step. In 15-minute balance settlement, netting results are always calculated with 15-minute precision, regardless of the accounting point’s metering accuracy or time step.

Calculation results and invoicing data

Market parties must use the netted values of the accounting point in the customer’s billing (except in cases where the accounting points belong to an energy community, in which case community calculation values are used). A separate information is maintained in Datahub to indicate which time series of the accounting point (metered energy, netted energy, or community energy) is the so-called “invoice relevant” information. However, this information is not stored as part of the accounting point information but provided to the parties as part of the DH-211, DH-231 and DH-251 forward messages in the ‘Invoice relevant’ information field. If the DSO reports the metering data for a time interval within which the invoice relevant information changes, Datahub splits the forward messages into two transactions covering the periods before and after the time of the change. Datahub also uses this information for balance settlement calculations (i.e., only the “invoice relevant” time series at the accounting point is used).

At the end of the calculation, Datahub forwards the calculated netted data to all parties entitled to the information (distribution network operators, suppliers and third parties). Market parties can also retrieve netting data separately using retrieval events. If necessary, only the netted time series used for billing can be retrieved with the event.

Retroactive corrections to related accounting point data

If the accounting point relation information is updated retroactively so that the accounting points’ netting status changes, Datahub performs the necessary netting and energy community calculations in connection with the update.

When relation information is added retroactively (DH-126), Datahub performs the calculations (netting and possible energy community calculations) and forwards the results of the calculations as normal to the parties. Datahub also updates the ‘Invoice relevant’ information (‘no’) for the accounting point’s metered time series in case it was the accounting point’s invoice relevant time series before the update (in case of an accounting point belonging to an energy community, the energy community time series is used for invoicing).

When relation information is removed retroactively (DH-127), Datahub hides the netting time series data that may have already been calculated for the accounting point and updates the ‘Invoice relevant’ information (‘yes’) for the accounting point’s metering time series (except for accounting points that belong to an energy community, in which case the energy community time series is used for invoicing). Additionally, Datahub performs a possible energy community calculation and forwards the results of calculation results normally to the parties. Hidden netting calculation results are no longer available to the parties and cannot be requested from Datahub.

Datahub does not forward the accounting point’s metering data, for which the ‘Invoice relevant’ information has changed, to the parties. When the DSO reports retroactive corrections to the accounting point relation information, the DSO must notify the parties of the corrections, so that the parties know to request the necessary metering data from Datahub. Notifying the parties is done outside of Datahub. Datahub does not send DH-122-2/3 notifications for retroactive relation information changes i(possible new notifications will be planned for a later version).