The consortium of Oil & Natural Gas Corporation (ONGC), BG and Reliance Industries (RIL) will raise the output from Panna-Mukta-Tapti fields in the western offshore of the country by 30% with an investment of Rs 2,192 crore ($520 million)."The gas production will increase from 13 million metric standard cubic meter per day (mmscmd) to 17 mmscmd by August /September," Sudhir Vasudevan, executive director (offshore), ONGC said.ONGC holds 40% stake in this field while BG and Reliance have 30% each. Earlier, the consortium invested $200 million in increasing oil production from the fields to 42,000 barrel per day from 29,000 barrel per day.The joint venture sells six mmscmd from the field to GAIL at $4.75 per million british thermal unit (MBTU). Another 4.8 mmscmd is sold to customers like GSPC at $4.08 per MBTU while the remaining 1.3 mmscmd is sold at $5.7 per MBTU."All the gas sales contracts are coming up for renewal in March 2008. We need to see what price we get then," Vasudevan said.The consortium was marketing 13 mmscmd gas jointly, but the additional volume expected from August/September would be sold by the three companies separately in proportion to their shareholding.Vasudevan said for ONGC's share of additional gas, the company has contracted sale with Torrent Power at $4.75 per MBTU and Rajasthan Vidyut Nigam at $4.6 per MBTU.