China’s record-breaking 600 MW/2.4 GWh battery hub hits first-phase milestone

• Huaneng’s 600 MW/2.4 GWh Longdong–Shandong battery project finishes installing all storage cabins at its first 300 MW block, clearing the way for testing and grid hook-up.

China has ticked off a key construction milestone on what will be its largest electro-chemical energy-storage plant to date. Project contractors have now installed the last of 240 prefabricated battery cabins and 60 power-conversion skids at the first 300 MW/1.2 GWh block of Huaneng’s 600 MW/2.4 GWh long-duration battery complex in Huanxian County, Qingyang, Gansu province. 

The two-block facility underpins the ±800 kV Longdong–Shandong UHVDC transmission link, a flagship “wind–solar–thermal-storage” programme in China’s 14th Five-Year Plan. Each block will provide four hours of discharge, using Huaneng’s single-stage distributed architecture: dozens of small PCS modules manage individual high-voltage battery strings, improving round-trip efficiency by roughly 4.6 percentage points versus traditional centralised layouts and extending available capacity retention by about five points over the plant’s lifetime.

Once both blocks are energised—targeted for the first half of 2025—the site will be able to shift up to 840 GWh of renewable generation onto the grid every year, enough to cover the daily electricity needs of about 480 000 households and to stabilise the high-voltage corridor that moves 8 GW of mixed clean power from resource-rich Gansu to demand-heavy Shandong.

The completion of cabin deployment paves the way for pre-commissioning tests, inverter synchronisation and grid-code compliance checks. Industry sources expect the first 300 MW tranche to begin trial operation by late Q3 2025, giving operators real-time data on system efficiency and thermal performance across Gansu’s desert climate—a proving ground that could influence design choices for China’s next wave of multi-gigawatt-hour storage builds.

Market analysts note that finishing the first 1.2 GWh segment on schedule will be critical for avoiding curtailment when the Longdong renewables base ramps up output this summer. It also signals growing confidence in China’s ability to scale modular lithium-iron-phosphate (LFP) systems beyond the 1 GWh mark, narrowing the gap with pumped hydro while offering far quicker deployment.