Bohai Oilfield Reaches 40 Million Tonnes Output Milestone, Setting New Record for China's Offshore Energy Sector

On 21 December, China National Offshore Oil Corporation (CNOOC) announced that the Bohai Oilfield — China's largest offshore oilfield — had achieved cumulative production exceeding 40 million tonnes of oil equivalent by 2025, marking a new historical record. The milestone provides strong support for national energy security as well as high-quality economic and social development.

Discovered in 1965, the Bohai Oilfield is widely regarded as the birthplace of China's offshore petroleum industry. As the country's highest-yielding and largest offshore oilfield, it currently operates more than 60 producing oil and gas fields and over 200 production facilities, with cumulative crude oil output surpassing 600 million tonnes. In recent years, the Bohai Oilfield has successively become China's largest crude oil production base and the nation's second-largest oil and gas field, serving as the primary frontline for offshore reserve expansion and production growth.

Under the guidance of China's Seven-Year Action Plan for Increasing Oil and Gas Reserves and Production, and based on the resource potential of the Bohai Oilfield, CNOOC set a target to achieve annual oil and gas output of 40 million tonnes by 2025. This objective requires a production leap from 30 million tonnes to 40 million tonnes within the planning period, while simultaneously addressing mounting challenges, including deteriorating resource conditions, increasing difficulty in sustaining output from mature fields, development-related technical bottlenecks, and production capacity saturation.

According to a representative from CNOOC's Tianjin Branch, production capacity construction at the Bohai Oilfield will accelerate comprehensively by 2025. This expansion will drive iterative upgrades in intelligent drilling and completion technologies, alongside the advancement of standardised engineering practices. Annual drilling and completion workloads are expected to reach record levels, enabling the rapid construction and commissioning of key projects such as Kenli 10-2 and Bozhong 26-6, including billion-tonne-class oilfields, to support the achievement of the 40 million-tonne production target.

In response to these challenges, the Bohai Oilfield has adopted a dual-driven strategy that advances both new and mature fields through technological empowerment. On the one hand, it has accelerated production ramp-up in newly developed fields while enhancing efficiency in mature assets; on the other, it has addressed development constraints through sustained technological innovation, promoting digital transformation and green, low-carbon initiatives to underpin production growth.

While expanding capacity in new fields, the Bohai Oilfield has remained focused on maximising output from mature fields. Technical teams have continued in-depth research on reservoir characterisation and residual oil distribution, successfully implementing secondary adjustment projects at the Suizhong 36-1 and Luda 5-2 fields. These efforts have revitalised mature fields developed over several decades, with mature-field crude oil output projected to exceed 32 million tonnes annually by 2025, thereby stabilising the production base.

Sustained production growth at the Bohai Oilfield has been underpinned by continuous technological innovation. Significant breakthroughs have been achieved in the domestic manufacturing of key oil and gas equipment. The successful application of China's first domestically produced shallow-water subsea production system represents a landmark shift from zero to one in the country's shallow-water development capabilities. In addition, a comprehensive offshore thermal recovery technology system for heavy oil has been established. High-temperature-resistant integrated injection–production equipment has enabled efficient development of unconventional heavy oil fields such as Luda 5-2 North and Jinzhou 23-2, supporting a historic increase in annual thermal recovery output from 300,000 tonnes to 2 million tonnes.

Alongside advances in core technologies and equipment, the Bohai Oilfield is accelerating digitalisation, intelligent operations, and green, low-carbon development. China's first offshore intelligent oilfield project — the Qinhuangdao 32-6 Intelligent Oilfield — has been completed, enabling traditional oil and gas production through unmanned or minimally manned operations and integrated production–operation coordination. Meanwhile, the country's largest offshore oilfield cluster shore power project has been fully implemented, with more than 80% of oilfields now connected to shore-based electricity. This shift from self-generated power to clean electricity has opened a new pathway for green transformation in offshore oilfield operations.

According to the latest data from China's National Energy Administration, during the 14th Five-Year Plan period, China's oil and natural gas production has maintained stable growth, with offshore crude oil emerging as a key driver. Offshore output has accounted for more than 60% of the nation's total new oil production for five consecutive years. As the “ballast stone” of China's offshore oil and gas sector, the Bohai Oilfield has recorded an average annual oil and gas output growth rate of 5% over the past five years, with its crude oil increment contributing nearly 40% of the national total.

A representative from CNOOC's Tianjin Branch noted that the company has remained committed to high-value exploration, discovering four billion-tonne-class oilfields consecutively over the past five years, thereby continuously strengthening the resource base for production growth. During the 15th Five-Year Plan period, priority will be given to the development of trillion-cubic-metre-class gas fields to further enhance offshore oil and gas supply security, injecting new momentum into China's energy self-sufficiency and maritime power development.