I-DEV0456: Application of calibration results to correct for lower accuracy readings during initial calibration from certain continuous flow meters.

Description of non-compliance with monitoring plan during the monitoring period
In accordance with the monitoring plan contained in the registered PDD, continuous V-cone flow meters were installed to measure the Amount of landfill gas flared i.e LFGflare,y and the Amount of landfill gas combusted in power plant i.e LFGelectricity,y . The instruments were provided by the manufacturer/supplier (Kingsway and KVS Lamways, Shanghai) having accuracy level of ±0.5%. These instruments were calibrated in accordance with manufacturer specification by Kingways controls (2006-1) and KVS Lamways, Shanghai before installations. As result of the calibration, certain instruments were shown to have a lower level of accuracy than indicated in the registered PDD. The difference between accuracy following calibration and the manufacturer’s specifications are shown below for the respective flow meters.

V-cone serial number Installation date
Replacement of equipment date Achieved accuracy as per calibration report Accuracy level in registered PDD and manufacturer’s specifications
10071507 (Flare #1 flow meter) 20/03/11 21/10/11 ±0.86%
(Validity of calibration till 23/08/2012) ±0.5%
10071508 (Flare#3 flow meter) 20/03/11 21/10/11 ±0.78%
(Validity of calibration till 23/08/2012) ±0.5%
10071511
(Engine#6 flow meter) 05/04/11 22/10/11 ±0.89%
(Validity of calibration till 22/08/2012) ±0.5%
10071512
(Engine#7 flow meter) 03/04/11 22/10/11 ±0.97%
(Validity of calibration till 22/08/2012) ±0.5%
10071501
(Engine#8 flow meter) 26/04/11 22/10/11 ±0.90%
(Validity of calibration till 22/08/2012) ±0.5%

In order to account for the lower accuracy identified for these instruments, the project participants propose to adjust the monitored flow data from the respective V-cone flow meters (indicated above) during their operation period by applying the maximum (lower) accuracy (1%) of the instrument to the measured values by all the above flow meter which will result in a conservative emission reductions. Furthermore, the PP has replaced all the V-cone flow meters which had a lower accuracy during October 2011 (dates as mentioned in the table above against respective flow meters) with newly calibrated meters which have an accuracy level within the ±0.5% range as per the registered PDD.

The deviation request applies only for some of the V-cones that were implemented from their respective installation dates as mentioned in the table above and were replaced on 21/10/11 and 22/10/11. Therefore, the lower accuracy flow meters were only used temporarily, and now they have been replaced with calibrated V-cone flow meters of required accuracy levels. All the flow meters are in compliance with the manufacturer’s specifications and the registered PDD, and hence there will be no need for a revision of the monitoring plan.

The correction made by the PPs is also in line with the method used in the newly adopted CDM project standard (EB65, Annex 5), Appendix 1: Changes that do not require prior approval by the board, para 4a which states that:
4. “If the monitoring equipment actually installed has a lower accuracy level than the one stipulated in the applied methodology and/or the registered monitoring plan, and the monitoring equipment is under the control of the project participants prior approval by the Board is not required if project participants adjust the value measured with the equipment as follows:
(a) If the parameter is used for calculating baseline GHG emissions, the difference between the accuracy level of the installed monitoring equipment and the accuracy prescribed by the applied methodology and/or the registered monitoring plan is deducted from the measured value”.
This is the approach applied by the PP but with a more conservative deduction of 1% for each meter.

The calculation of the emission reductions using the full uncorrected flow monitoring data from the forementioned V-cones resulted in 176,118 tCO2e emission reductions during the current monitoring period.
By applying a 1% reduction in monitored flow data from the aforementioned V-cones, the emission reductions are calculated as 175,484 tCO2e emission reductions during the current monitoring period.
Therefore, the above adjustment results in a conservative calculation of emission reductions of used of 175,484 which is a reduction of 634 tCO2e compared to the actual monitored data.