TORONTO (miningweekly.com) – New preliminary data from the China Statistical Abstract 2015 (CSA2015) revealed an upward revision to China's historical coal consumption and production, the US Energy Information Agency (EIA) said on Wednesday.

The EIA’s latest ‘Today in Energy’ brief reported that energy-content-based coal consumption from 2000 to 2013 was up to 14% higher, at almost 120-quadrillion British thermal units a year, than previously reported, while coal output was up to 7% higher at about seven-quadrillion British thermal units a year

These revisions also affected China's total primary energy consumption and production, which were also higher than previously reported – up to 11% and 7% in some years, respectively, mainly owing to the revisions to coal, the EIA stated.

In 2014, energy-content-based coal consumption was essentially flat and output declined by 2.6%.

China's National Bureau of Statistics (NBS) typically published the CSA in May. The CSA provided the yearly total primary energy consumption and production in tons of standard coal equivalent, which reflected the energy content, but not the physical tonnage of coal consumption and output.

Final and detailed statistics were expected to be published in the China Statistical Yearbook, which was typically released in September or October each year.

This year, the CSA2015 revised both the totals and the coal shares for all years since 2000, compared with what was provided in China Statistical Yearbook 2014, the most recent final statistics.

In the absence of official revisions to physical tonnage of coal consumption and production, the EIA independently assessed the historical average heat content of coal consumed and that of raw coal produced in China to estimate tonnages. The assessment factored in information from several sources, including information from NBS and other Chinese statistical agencies, industry reports, consultant survey results, expert interviews and academic papers related to raw coal heat content, and coal washing rates and yields by coal type.

These estimates showed that the physical tonnage of coal consumption decreased by about 2%, in 2014, to about 4.25-billion tons of coal, with raw coal output following the same projected trend.

The EIA noted that CSA2015 did not provide specific explanations for the extensive revisions to historical coal data. However, the direction and the magnitude of the revision were mainly consistent with the widely reported issues associated with Chinese coal statistics, which were likely the reasons for previous upward revisions of coal consumption.

Other explanations potentially responsible for the revisions were disagreements between national totals and the sum of provincial reports, misalignment of reporting methods and inherent difficulties in achieving data accuracy in a constantly and rapidly changing market as large as China's. Uncertainties remained in China's coal data, which should be recognised in future analysis, the agency advised.