REVIEW REPORT FOR NEW ZEALAND (EXAMPLE)

24. Overall, methodological approaches, AD and EFs used to estimate emissions for the energy sector are presented in the NIR in a transparent manner. Tier 1 methods are used for all categories. AD is compiled by the Ministry of Economic Development (MED), which is responsible for estimating the emissions of the energy sector, based on its own database and on the data compiled by Statistics New Zealand. The AD used for emission estimates together with other energy statistics are regularly published in the New Zealand Energy Data File (September 2006 edition) which is available on the MED website. Country-specific EFs are used for estimations of CO₂ emissions, while mostly IPCC tier 1 or tier 2 EFs are used for non-CO₂ gases. The NIR includes the complete set of EFs, the energy balance and the worksheets used to estimate the emissions. The ERT commends New Zealand’s efforts in improving the transparency of the energy sector in the NIR.

25. Three external reviews of the energy sector have been undertaken, focusing on emissions estimates (Clarkson, 2002), emission factors (Hale and Twomey, 2003) and the overall sectoral inventory (Goldthorpe, 2006). The ERT commends New Zealand for its initiatives to improve estimates. However, there is a lack of QA/QC procedures for the use of plant-specific data (EFs, AD, and emission estimates) as well as for the process of taking decisions that are based on expert judgment. This led to a lack of transparency in some cases in oil and natural gas categories. The ERT recommends that data produced externally be subject to procedures in accordance with the IPCC good practice guidance, including the QA/QC guidance. The ERT notes that additional documentation and explanatory background material could be incorporated into the electronic and paper archives. In addition, the ERT encourages New Zealand to provide information in the NIR on how experts are selected and the procedures to elicit expert opinion.

26. Emissions estimates have been recalculated for all years from 1990 to 2003, resulting in minor changes. For the period 1990–2002, except for 1997 and 2003, the recalculations of estimates reported in the 2006 submission resulted in increases in the total figures for the aggregated emissions of CO₂, CH_4, and N₂O of about 0.2 per cent. For 1997 and 2003 the recalculations resulted in decreases of 0.03 and 0.05 per cent respectively. The NIR reports that these differences are associated with minor rounding errors and updates to data in the New Zealand Energy Data File (September 2006 edition).