State-run BHEL on Wednesday said it has commissioned a captive gas-based power station at a refinery in Oman. The 26-MW Gas Turbine Generator was put on stream at the Oman Refinery and Petrochemical plant in Muscat, an official statement said. This is the second such unit to be commissioned by Bhel at the refinery. Another unit of similar rating was commissioned at the same project in May, 2010.