Propuesta arquitectónica

· Forward all metering data that has altered after the closing of the imbalances to the RE

· Carry out correction calculations of errors remaining in the imbalances including regular billing, with appendices in a specified form, on schedule

· Deliver the information needed in the revision calculation on the REs’ request

· Refund or charge the customer with respect to an error if the RE is no longer entitled/obliged to do so

Tasks of the supplier:

· Receive the metering and imbalance settlement data sent by the DSO

· For its own part monitor that the metering data received from the DSOs correspond with the imbalance settlement data received from the BRP

· Receive and carry out the correction invoices or refunds for imbalance errors calculated by the DSO

· Invoice or refund the customer for incorrect invoicing resulting from an imbalance error

Timetable

DSO and the customer's current supplier will correct the error to the customer with respect to their own proportion of the invoice. The DSO will correct the share of network services for the entire period of error, and the customer’s current electricity supplier will correct the share of electricity for its own contract period. If the customer has switched supplier within six weeks of when the error was noticed and the customer was notified of it, the customer’s current and previous supplier will correct their own share of the error in invoicing for their own contract period. This will also be carried out in situations where the

customer of a metering point has moved out of the site in less than six weeks of when the error was noticed and the customer was notified of it. Thus, the suppliers of both customers (the current customer at the metering point and the customer that moved out) will correct their own share of the error in invoicing for the period of their own contract.

If the error has lasted longer than the latest or preceding electricity sales (on the terms described above) contract for the customer/metering point, the DSO shall also correct the customer’s invoicing with respect to sales for the period prior to the current/preceding contract. This will also be carried out with errors that have lasted longer than three years for the period exceeding three years. The customer cannot be charged for metering errors lasting longer than three years. Each party may deviate from the customer’s correction invoicing for their own part for the benefit of the customer.

The length of the correction period of imbalance errors for each metering point is three years, which is the same as the correction period of customer invoicing. The parties may also demand their receivables based on metering or invoicing errors for the past three years. The three-year period is calculated retrospectively from the moment when the customer has been informed of the detected error. Moreover, this period will take into account sites that are billed only once a year.

Three-year calculation method must be taken into account in imbalance correction calculation so that the suppliers’ maximum total period to be corrected is three years from the moment when the customer has been informed of the error.

Corrections of imbalance errors between suppliers of hourly metered sites are made regularly three times a year. The days when the correction periods end are 30th of April, 31st of August and 31st of December. Correspondingly, the materials for corrections are obtained on 15th of May, 15th of September and 15th of January or the next working day. Correction periods that progress in a sliding way, overlap with each other to a great degree. This enables a long correction period, as well as regular and sufficiently frequent financial corrections of imbalance errors between market participants.

In accordance with the above, the maximum total correction period to be calculated is three years and four months. This is described in the following picture in which the arrow describes the date of sending the imbalance bill concerning the period. This time schedule is not applied in the handling of load curve sites.

Figure 14. Timing of the imbalance correction periods.

The current supplier of the customer of the metering point with a contract with the customer at the time of observing the error will refund or invoice the customer due to any incorrect invoicing with respect to electricity for the period of its contract. For this period, the monetary compensation of imbalance errors between market participants takes place between the supplier/s in question and the supplier with the delivery obligation while the DSO carries out the necessary calculations and billing.

If the previous customer relationship of the metering point has ended as a result of a supplier switch or move during the past six weeks, calculated from the moment the error was noticed and the customer was notified of it, both of the electricity suppliers of the metering point will refund or bill the customer/s due to any incorrect invoicing with respect to electricity for the period of their own contract.

The consumer may, however, present a claim for receivables based on metering or billing errors for the entire period during which the error has affected invoicing, but not for longer than ten years if the moment the error took place and the effects of the error on invoicing can be verified afterwards. If the error with a consumer has continued for more than 3 years or it is not noticed until after three years, the DSO instead of the supplier shall be responsible for the payment of the refund to the customer for the period exceeding three years. The division of responsibilities is described in the appendix 1 and 2 (Figure 15 and Figure 16).

If the invoicing for electricity sales is corrected by the customer’s electricity supplier, the price of the contract valid at the time when the error took place shall be used as the sales price. If the invoice for electricity sales is corrected by the DSO, the DSO shall use the most suitable public product or tariff of the RE who has the delivery obligation in the area of responsibility in the distribution network as the sales

price. However, if the user presents the DSO with an account of the prices applied to its electricity acquisition at the time in question, these prices shall be used.

No interest is payable on the determined extra charge or refund for the period of its accrual. The user must be granted a reasonable payment period for the extra charge. If the user will not pay the invoice for the extra charge within the payment period, a penal interest on delayed payment in accordance with the can be charged for it after the due date.

If the DSO carries out the correction of customer invoicing, the customer invoicing already carried out by the RE will not be corrected, but the supplier has invoiced the customer according to the energy

consumption reported to the supplier by the DSO in due course. In this respect, an imbalance error remaining in the original imbalance calculation has remained in the imbalance (residual curve) of the supplier with a delivery obligation in the network. For this period, the monetary refund of balance errors between the market participants takes place between the DSO and the supplier with a delivery obligation in the network. With respect to errors dating back over three years, no corrections are made to the imbalance errors between the market participants, and the refund paid to the customer will remain as a loss for the DSO.

The suppliers will be sent the changed metering data on a regular basis throughout the customer

contract. The DSO must note that the data changed during the imbalance correction period must be sent to all the suppliers that carry out customer’s correction billing. Therefore, if necessary, the data must also be sent to the previous supplier of the customer/metering point even if the customer contract in question has ended at the time of noticing the error. This information must be sent at the latest by the stage when the concerned correction material for imbalance errors is calculated and sent to the supplier. See calculation examples from Appendix 1 and 2.

As in the sending of hourly series and in the balance settlement on the electricity market in general, the official local time is always complied with also in the correction of balance errors.