When you open your phone and see the news that "the cumulative installed capacity of wind and solar power has exceeded 1.6 billion kilowatts," you probably wouldn't imagine that behind this seemingly impressive figure, China's power system is facing the most severe security challenges in its history.
In 2025, the newly installed capacity of new energy sources nationwide reached 227 million kilowatts, accounting for 70.7% of the total newly installed capacity of all power sources. We are rapidly entering a "dual-high" era—a high proportion of new energy and a high proportion of power electronic equipment.
Wind and solar power generation is inherently dependent on weather conditions, while power electronic equipment is characterized by "no inertia and weak damping." This means that the "strong power grid" once supported by thermal and hydropower is becoming a "fragile grid."
In this once-in-a-century transformation of the power system, energy storage technology is undergoing a historic leap from "grid-following" to "grid-building."
Energy storage is no longer just a "power bank" for the power grid, but is becoming an indispensable "ballast" and "stabilizer" for the new power system.
01. Grid-Mounted Energy Storage: Once the King, Now the Weakness
In traditional power systems, the massive rotor of a synchronous generator acts like a heavy flywheel, providing ample rotational inertia. When the grid is disturbed, these flywheels automatically release or absorb energy to maintain frequency stability.
Grid-mounted energy storage was designed for this era. It employs a current source control mode, using a phase-locked loop (PLL) to track the grid's voltage, frequency, and phase in real time, passively adjusting its output power according to dispatch commands.
Simply put, grid-mounted energy storage is like a "tail" to the grid, doing whatever the grid signals. Its mature technology and low cost allowed it to dominate the energy storage market until 2020.
However, as the proportion of new energy installations exceeded 30%, especially in the barren western regions where wind and solar power accounted for over 50%, the limitations of grid-mounted energy storage became glaringly apparent.
Grid inertia is like the weight of a human body. Traditional thermal power units are robust and resistant to shocks, making them less prone to imbalance. In contrast, power grids heavily integrated with renewable energy sources are vulnerable, easily experiencing frequency oscillations and voltage drops with even minor disturbances.
Low-probability events such as cloud cover or wind turbine disconnection can trigger sudden frequency changes in the power grid. Even more alarming is that when a grid fault occurs, grid-connected energy storage can trigger a "self-protective escape," disconnecting from the grid along with renewable energy plants, further widening the power gap and creating a vicious cycle
In 2023, a major renewable energy province experienced a widespread power outage caused by a localized fault. Subsequent analysis revealed that a large amount of grid-connected energy storage not only failed to provide support at the critical moment but also exacerbated the system collapse.
This incident served as a wake-up call for the entire industry: grid-connected energy storage can no longer meet the needs of modern power systems; we need a new technology capable of actively supporting the power grid.
02. Grid-Based Energy Storage: The Grid's "Superhero" Arrives
Faced with the severe challenges of high-voltage and high-efficiency power grids, grid-based energy storage has emerged. It no longer passively follows the grid but, through Virtual Synchronous Generator (VSG) technology, simulates the operating characteristics of traditional synchronous generators, autonomously establishing and maintaining the grid's voltage and frequency references.
If grid-following energy storage is a "follower," then grid-based energy storage is a "superhero."
It possesses three superpowers:
1. Millisecond-Level Inertia Support: Grid-based energy storage can simulate the flywheel effect of a synchronous generator when the grid frequency changes, releasing or absorbing energy to suppress frequency abrupt changes. This fills the inertia gap in high-energy-density power grids, making the grid "strong" again.
2. Active Fault Rift-Through: When the grid experiences severe faults such as short circuits, grid-based energy storage can provide short-term overload capacity of three times its rated current, actively supporting the grid voltage and helping the system overcome difficulties. This contrasts sharply with the "escape" behavior of grid-following energy storage.
3. Black Start and Isolated Operation Grid-based energy storage can operate independently without relying on the power grid. This means that in the event of a complete grid failure, it can act as a "spark" to gradually restore power to the entire grid. Simultaneously, it can provide independent and stable power to remote areas and islands.
On May 31, 2024, the 100MW/200MWh grid-based energy storage power station of China Green Development Group in Haixi Prefecture, Qinghai Province, successfully completed an artificial short-circuit disturbance test. When a three-phase short-circuit fault occurred in the system, the grid-based energy storage actively supported the grid voltage in just 200 milliseconds, achieving fault ride-through.
This milestone event signifies that grid-based energy storage technology has matured and is ready for large-scale application.
04. Technological Breakthrough: From Laboratory to Industrialization
The rise of grid-based energy storage is not an overnight achievement, but the result of years of technological accumulation. In recent years, three major technological breakthroughs have laid a solid foundation for the large-scale application of grid-based energy storage.
First, the Evolution of Virtual Synchronous Machine Technology
Virtual synchronous machine technology is the core of grid-based energy storage. Early VSG technology suffered from low single-unit control accuracy and oscillation issues when multiple units were connected in parallel. These problems have now been effectively solved through advanced control algorithms and multi-unit collaborative technologies.
Second, the application of wide-bandgap semiconductor devices
The application of wide-bandgap semiconductor devices such as SiC (silicon carbide) and GaN (gallium nitride) has brought revolutionary changes to grid-connected converters (PCS). SiC MOSFETs can significantly reduce switching losses by 50%–70% and increase switching frequency, thereby improving grid response speed and system efficiency.
Third, the development of system-level integration technologies
Grid-connected technology is no longer limited to the PCS level but is deeply integrated at the system level. The development of grid-connected BMS, grid-connected EMS, and panoramic wind-solar-storage grid-connected technologies enables grid-connected energy storage to be better integrated with new energy power generation, achieving synergistic optimization of "source-grid-load-storage".
05. The Future is Here: Grid-Based Energy Storage Enters its Explosive Growth Year
2026 is widely considered by the energy storage industry to be the "explosive growth year" for grid-based energy storage. The triple drivers of policy, technology, and the market are propelling grid-based energy storage from "pilot demonstrations" to a new stage of "large-scale application."
At the policy level, the government has released clear signals. In June 2025, the National Energy Administration issued a notice, explicitly stating for the first time that the penetration rate of grid-based energy storage must exceed 30%. Document No. 93, issued in November of the same year, mentioned "grid-based" technology 23 times, directly listing it as a necessary threshold for achieving "system friendliness" in new energy power plants.
From "encouraging pilot projects" to "mandatory construction," grid-based energy storage has completely transformed from an optional technology into an "entry ticket" for new energy grid connection.
At the market level, a trillion-dollar blue ocean is forming. According to industry forecasts, by 2030, the market size of grid-based energy storage in China will exceed 300 billion yuan, accounting for 30% to 50% of the total installed capacity of new energy storage.
Industry giants such as Sungrow Power, Huawei, Envision, NARI Group, and Kehua Energy have already begun their strategic deployments to seize this strategic high ground.
Technically, "dual-mode energy storage" will become an important development direction. This type of energy storage system operates in grid-connected mode under normal circumstances to ensure economic efficiency; in the event of a grid crisis, it automatically switches to grid-connected mode to provide necessary support capabilities.
Simultaneously, grid-connected technology will be deeply integrated with new energy power generation, forming "grid-connected wind-solar-storage integrated" power plants. These power plants are no longer simply a combination of "wind and solar + energy storage," but can operate as a primary power source, just like traditional thermal power plants.
Conclusion: A Revolution Changing the Future of Energy
From grid-connected to grid-connected, this is not only an upgrade in energy storage technology, but also a revolution in the operating philosophy of the power system.
Guided by the "dual carbon" goals, China is building a new power system with new energy sources as its core. In this system, grid-based energy storage will play an increasingly important role. It is not only a key technology for solving the challenge of integrating high-proportion new energy sources into the grid, but also a crucial support for ensuring national energy security and achieving energy independence.
The future is here; the era of grid-based energy storage has begun! Let us participate in and witness this great revolution that will change the future of energy!
