Large quantities of natural gas are imported by and traded between the Member States of the Community. The price of the natural gas is related to the energy content. The discrepancies between laboratories can be as large as +/- 0.5 %. Real disputes are not frequent because the contracts specify how differences between their measurements will be handled, but the sum dealt with in such settlements is estimated at several 107 ECU per year, hence the need for improving the accuracy of the measurements. An intercomparison was held to assess if improvement of the measurements could be achieved.
The GCV (Gross Calorific Value) of 2 batches of natural gas was determined by 14 European laboratories using two methods:
- direct calorimetry;
- determination of the gas composition by chromatography and calculation of the GCV.
For calorimetry the spread of results was within +/- 0.15 % (coefficient of variation). The laboratories using the most accurate methodologies agreed within +/- 0.09 %.
For gas chromatography, the spread of results was +/- 0.15 %, for the most accurate results +/- 0.03%. The difference between the mean results of calorimetry and the mean value derived from gas chromatography was 0.01 - 0.02 %.
Final report in print
Funding SchemeCSC - Cost-sharing contracts
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