Bibiyana has more gas than estimated, claims Chevron

American company Chevron has submitted to the Petrobangla a new estimate of gas reserve in the Bibiyana field, putting the ‘proven recoverable reserve’ at 4.4 trillion cubic feet, up by a staggering amount of 2.7 TCF, said Petrobangla officials.
Energy officials at a meeting with Prime Minister Sheikh Hasina on Wednesday presented the new estimate of gas reserve in the country’s second largest gas-field.
As per the new estimate, the ‘gas in place or proven gas reserve’ of the field has been put at 6.6 trillion cubic feet, of which 4.4 TCF is recoverable, said Petrobangla officials. The earlier estimate had showed that the proven gas reserve was around 2.51 TCF, and Petrobangla had estimated that around 60-70 per cent of the reserve was recoverable.
‘The PM told the meeting that it was good news for the country that the Bibiyana gas reserve was much higher than the earlier estimate. She was hopeful that more gas would be found,’ said a source who was present at the meeting.
Petrobangla officials said that Chevron submitted its new estimate, made by another US consultant, Degolyer and MacNaughton, on September 13.
‘We have now formed a committee to scrutinise the company’s new estimate. If the findings are right, production at the Bibiyana gas-field could be increased to around 1,000 million cubic feet per day in the next two years from the present production of 670mmcfd,’ Petrobangla’s chairman Muqtadir Ali told New Age on Thursday.
He said that the new estimate puts the total ‘proven plus provable reserve’ at more than 7 TCF and the ‘proven plus probable plus possible’ reserve at more than 8 TCF.
He claimed that the new estimate would remove the confusion surrounding the gas reserve and daily production rate at the Bibiyana field.
Energy experts and a seven-member expert committee of Petrobangla had earlier criticised Petrobangla for allowing Chevron to extract more than 450mmcfd of gas as the second estimate of gas reserve by another US company, Ryder and Scott, had put the proven reserve at 2.51 TCF.
After the initial estimate of Degolyer and MacNaughton put the proven reserve at 1.2 TCF in 2000, Chervon and Petrobangla agreed to appoint Ryder and Scott for again estimating the reserve.
After Ryder and Scott put the proven reserve at 2.51 TCF in 2008, Chevron insisted on a further study of the reserve and Petrobangla earlier this year allowed Chevron to appoint D&M.
‘When the two initial estimates were made, there was no data on gas pressure in the wellhead. After three years of production, D&M got all the data and found the “gas in place” or “proven reserve” of the field at 6.6 TCF, of which 4.4 TCF was recoverable,’ said Muqtadir.
One of the members of expert committee that scrutinised the report of the second estimate of the Ryder and Scott, however, was sceptical about the estimate.
‘The data we went through showed there was undeveloped proven reserve. I do not know whether they counted the undeveloped proven reserve to show a larger gas reserve. I will have to go through the detailed report of the D&M before making any comment,’ he said.
Muqtadir, however, said that all the data on gas pressure in the Bibiyana gas-field showed that the reserve would be higher than what Ryder and Scott had estimated.
The Titas gas-field of the Bangladesh Gas Fields Company Ltd is the largest gas-field in the country with a proven reserve of 9 TCF.