1.The operator shall determine the activity data of a source stream in one of the following ways:
(a)based on continual metering at the process which causes the emissions;
(b)based on aggregation of metering of quantities separately delivered taking into account relevant stock changes.
2.For the purposes of point (b) of paragraph 1, the quantity of fuel or material processed during the reporting period shall be calculated as the quantity of fuel or material purchased during the reporting period, minus the quantity of fuel or material exported from the installation, plus the quantity of fuel or material in stock at the beginning of the reporting period, minus the quantity of fuel or material in stock at the end of the reporting period.
Where it is technically not feasible or would incur unreasonable costs to determine quantities in stock by direct measurement, the operator may estimate those quantities based on one of the following:
(a)data from previous years and correlated with output for the reporting period;
(b)documented procedures and respective data in audited financial statements for the reporting period.
Where the determination of activity data for the entire calendar year is technically not feasible or would incur unreasonable costs, the operator may choose the next most appropriate day to separate a reporting year from the following one, and reconcile accordingly to the calendar year required. The deviations involved for one or more source streams shall be clearly recorded, form the basis of a value representative for the calendar year, and be considered consistently in relation to the next year.
1.For determining the activity data in accordance with Article 27, the operator shall use metering results based on measurement systems under its own control at the installation, provided that all of the following conditions are complied with:
(a)the operator must carry out an uncertainty assessment and ensures that the uncertainty threshold of the relevant tier level is met;
(b)the operator must ensure at least once per year, and after each calibration of measuring instruments, that the calibration results multiplied by a conservative adjustment factor based on an appropriate time series of previous calibrations of that or similar measuring instruments for taking into account the effect of uncertainty in service, are compared with the relevant uncertainty thresholds.
Where tier thresholds approved in accordance with Article 12 are exceeded or equipment found not to conform to other requirements, the operator shall take corrective action without undue delay and notify the competent authority thereof.
2.The operator shall provide the uncertainty assessment referred to in point (a) of paragraph 1 to the competent authority when notifying a new monitoring plan or when it is relevant for a change to the approved monitoring plan.
The assessment shall comprise the specified uncertainty of the applied measuring instruments, uncertainty associated with the calibration, and any additional uncertainty connected to how the measuring instruments are used in practice. Uncertainty related to stock changes shall be included in the uncertainty assessment where the storage facilities are capable of containing at least 5 % of the annual used quantity of the fuel or material considered. When carrying out the assessment, the operator shall take into account the fact that the stated values used to define tier uncertainty thresholds in Annex II refer to the uncertainty over the full reporting period.
The operator may simplify the uncertainty assessment by assuming that the maximum permissible errors specified for the measuring instrument in service, or where lower, the uncertainty obtained by calibration, multiplied by a conservative adjustment factor for taking into account the effect of uncertainty in service, is to be regarded as the uncertainty over the whole reporting period as required by the tier definitions in Annex II, provided that measuring instruments are installed in an environment appropriate for their use specifications.
3.Notwithstanding paragraph 2, the competent authority may allow the operator to use metering results based on measurement systems under its own control at the installation, where the operator provides evidence that the measuring instruments applied are subject to relevant national legal metrological control.
For that purpose, the maximum permissible error in service allowed by the relevant national legislation on legal metrological control for the relevant measuring task may be used as the uncertainty value without providing further evidence.
1.Where, based on a simplified uncertainty assessment, the use of measurement systems outside the operator’s own control, compared to the use of those within the operator’s own control pursuant to Article 28, allows the operator to comply with at least as high a tier, gives more reliable results and is less prone to control risks, the operator shall determine the activity data from measurement systems outside its own control.
To that end, the operator may revert to one of the following data sources:
(a)amounts from invoices issued by a trade partner, provided that a commercial transaction between two independent trade partners takes place;
(b)direct readings from the measurement systems.
2.The operator shall ensure compliance with the applicable tier pursuant to Article 26.
To that end, the maximum permissible error in service allowed by relevant legislation for national legal metrological control for the relevant commercial transaction may be used as uncertainty without providing further evidence.
Where the applicable requirements under national legal metrological control are less stringent than the applicable tier pursuant to Article 26, the operator shall obtain evidence on the applicable uncertainty from the trade partner responsible for the measurement system.