The world's first 5-megawatt (MW) class offshore high-temperature exhaust gas waste heat Organic Rankine Cycle (ORC) power generation unit has surpassed 10 million kilowatt-hours (kWh) in cumulative power generation at the Wenchang 9-7 oilfield on Tuesday, said its operator.

Spearheaded by the research institute of China National Offshore Oil Corporation (CNOOC), the project marks the system's transition to stable and highly efficient operation, utilizing previously wasted exhaust gas heat to generate clean electricity.

It represents a major technological breakthrough in offshore waste heat recovery for the country, it said.

Offshore platforms, which traditionally rely on power stations fueled by burning oil and natural gas, emit large amounts of high-temperature exhaust gas. The ORC unit intercepts this waste heat and uses it as a thermal source.

Since its installation, the system has successfully boosted the platform's power supply capacity by 20 percent and enhanced fuel utilization efficiency by 8 percent, significantly improving overall energy efficiency.

To date, the Wenchang 9-7 platform ORC power generation unit has generated over 10 million kWh of electricity, cumulatively saving approximately 6 million cubic meters of natural gas, enough to supply the annual domestic gas needs of 20,000 households.

zhengxin@chinadaily.com.cn