China Three Gorges Corporation (CTG) has begun commercial trial operations at the Hami Hybrid Solar Power Plant in Xinjiang, a 1-gigawatt (GW) renewable energy facility that combines photovoltaic (PV) solar panels with concentrated solar power (CSP). The project is the world’s largest hybrid solar plant and uses molten salt thermal storage to continue generating electricity for up to eight hours after sunset—without relying on lithium batteries.

Located in the Gobi Desert near Hami, the facility captures solar energy during the day and stores excess heat in molten salt. The stored thermal energy is later converted into steam to drive a turbine, supplying electricity during evening hours when conventional solar panels are no longer producing power.

Figure 1. Hybrid Solar Plant.

Combining Solar Power with Thermal Storage

The Hami project integrates 900 megawatts of photovoltaic capacity with a 100 MW concentrated solar power system spread across nearly 4,500 acres. During daylight hours, the PV array delivers electricity directly to the grid, while more than 260,000 sun-tracking mirrors concentrate sunlight onto receivers that heat molten salt to approximately 550°C (1,022°F). Figure 1 shows hybrid solar plant.

The stored heat is retained for several hours and later used to generate electricity after sunset, providing a reliable source of clean energy during periods of high evening demand. CTG's advanced linear Fresnel design also improves heat conversion efficiency while allowing maintenance work without interrupting plant operations.

Reliable Power Beyond Daylight

Although commercial trial operations officially began in July, the facility has been supplying electricity to the grid since September 2025. According to CTG, the plant is expected to generate approximately 2.07 terawatt-hours of electricity annually, enough to power around 830,000 homes while reducing carbon dioxide emissions by an estimated 1.63 million metric tons each year.

A centralized control system coordinates both the photovoltaic and CSP sections, enabling rapid grid response and maintaining stable power delivery with high operational precision.

A New Approach to Long-Duration Energy Storage

Unlike lithium-ion batteries, which are typically designed for short-term energy storage, molten salt systems can store thermal energy for extended periods, making them well suited for supplying electricity long after sunset [1]. This capability helps improve grid stability while increasing the utilization of renewable energy.

The success of the Hami project marks a significant milestone in large-scale clean energy deployment. Building on this achievement, CTG plans to expand the Hami energy base to 3 GW, while additional hybrid solar and CSP projects are already under construction nearby. As demand for reliable renewable energy grows, molten salt thermal storage could become an increasingly important solution for delivering continuous, low-carbon electricity around the clock.

Reference:

1. https://interestingengineering.com/energy/worlds-largest-hybrid-solar-plant

Cite this article:

Keerthana S (2026), World’s Biggest Hybrid Solar Plant Stores Heat for Nighttime Power, AnaTechMaz, pp.471