Turbine maker Mingyang Smart Energy said one of its machines is now installed on a pioneering deep-water floating wind platform that will supply green power to offshore oil and gas production facilities operated by China National Offshore Oil Corporation (CNOOC).

The floating wind platform, called Haiyou Guanlan, and its 7.25-megawatt typhoon-proof turbine will operate in a water depth of 120 metres at CNOOC’s Wenchang oil and gas project in the South China Sea, Mingyang said in a social media post.

The floating structure, built by Chinese yard Offshore Oil Engineering Company (COOEC), will be located in the Beibu Gulf at a distance of 136-kilometres from Yangjiang city, Hainan province.

The 200-metre high structure is built around a 35-metre central column and comprises 30 modules and structures carrying a total steel weight of 4000 tonnes, according to CNOOC.

According to Yang Xiaolong, floater manager of the CNOOC Design Institute, the Haiyou Guanlan is built to resist typhoons with magnitude of 17.

The structure applies a spread mooring system and online tensioner to enhance stability to such an extent that the floating platform will stay in operation even when horizontal displacement reaches 33.8 metres under extreme weather conditions.

Wenchang’s power utilities face a lack of gas supply to fuel the engines and CNOOC Ltd is keen to supplement the power supply via offshore wind as part of its efforts to reduce carbon emissions.

CNOOC said an expected 22 million kilowatt hours per annum of electricity generated from the floating wind farm will be sent via a five-kilometre subsea dynamic cable to the Wenchang oil complex, helping to cut carbon dioxide emissions by 22,000 tonnes per annum.

CNOOC’s project is not the first of its kind in the world. Norwegian operator Equinor brought the first turbine for the Hywind Tampen floating wind farm online last November, providing power to the Gullfaks A platform in the North Sea.

The Norwegian wind farm is located some 140 kilometres from shore at water depths between 260 and 300 metres. With seven turbines on stream, Hywind Tampen is expected to reach a capacity of 60 MW.

New path

Kang Siwei, general manager of construction department of CNOOC Energy, said that Haiyou Guanlan is China’s first floater able to operate in water depths beyond 100 metres and further than 100 kilometres from shore. The previous record was a water depth of 50 metres.

CNOOC Energy general manager Yang Yun said that deep-water offshore wind is the beginning of a new path for CNOOC to diversify from offshore oil and gas to renewable energy.

CNOOC said that China now has more than 20 offshore wind farms with total capacity exceeding 30 gigawatts.

The Wenchang oil complex comprises two wellhead platforms, Wenchang 13-1 and Wenchang 13-2. CNOOC Ltd has just completed refitting the two unmanned platforms into manned facilities for safety reasons.

Oil is produced to the Nanhai Fenjing floating production, storage and offloading vessel, from where crude is shipped to an onshore terminal by shuttle tankers.