Oasis expansion fuels takeoff of computing power

The expansion project of the No 3 main transformer at Nanjing’s 110-kilovolt Oasis Substation was energized on June 3, adding one 50 mega volt-amperes main transformer and fourteen 10-kV outgoing feeder lines. The substation’s total power supply capacity increased by 50 percent, breaking the power bottleneck for the computing power industry in the Hexi area of Jianye district, Nanjing, and laying a solid power foundation for the high‑quality development of the regional digital economy.

Located in southwest Hexi area of Jianye, the Oasis Substation is a key power facility built to support the local computing power industry. A decade ago, this area was still undeveloped land. With the successive arrival of leading enterprises, such as Alibaba’s Jiangsu Headquarters and Xiaomi’s East China headquarters, the digital industry in the area has rapidly clustered.

Electricity and computing power are advancing in sync. In 2022, the Oasis Substation was completed and put into operation, equipped with two 50 MVA main transformers and an intelligent high‑definition video control system. It adopted an operation mode featuring intelligent inspections and the remote replacement of on‑site operations, greatly improving inspection and work efficiency, and became a key power source supporting early business production in the area.

Aerial view of No 3 main transformer at Nanjing’s 110-kilovolt Oasis Substation. [Photo provided to chinadaily.com.cn]

With power support, the expansion of the computing power industry has exceeded expectations. Since 2025, the construction of the Hexi Central Science and Technology Innovation Zone has accelerated. Tech projects such as JD and BMW’s Asia R&D Center have settled in the area one after another. Southwest Hexi has risen as a regional computing power hub. The local power load has exploded, with newly added power connection capacity reaching 289.4 MVA. The original two main transformers at the Oasis Substation quickly became fully loaded. Nearby 110 kV substations either have saturated loads with no room for expansion or are too far away to meet core‑area power supply standards. Power capacity directly determines the upper limit of computing power, making expansion the only way forward.

Power supply staff members conduct on-site inspections at Oasis Substation to check the operating status of upgraded equipment. [Photo provided to chinadaily.com.cn]

To match the rapid growth of industrial electricity demand, State Grid Nanjing Power Supply Co officially launched the expansion project for the No 3 main transformer at the Oasis Substation in the second half of 2025. This indoor substation is in a prime urban area with tight construction space, and during construction, the existing equipment remained energized, posing high risks and difficulties for construction management. The project team optimized the construction plan, adopting a partitioned isolation and modular construction approach. Using new techniques such as rail‑guided (sliding) and hydraulic lifting, they achieved millimeter‑precision installation of the main transformer, ensuring seamless integration of old and new equipment, with zero safety incidents throughout the process.