In the mountainous border regions of Hekou, Honghe Prefecture, Yunnan Province, characterized by steep valleys and frequent natural disasters, the lack of grid power and fiber optic networks has long been a major challenge for communication network construction. Recently, China Mobile Yunnan Company solved this problem by adopting new technologies such as low-voltage gallium nitride (GaN), pioneering a new path for building pure green energy stations in frontier areas. This move brings GaN power devices into a new arena—the energy systems of communication base stations.
1. China Mobile: Integrating GaN Technology into Frontier Base Station PV Systems
Recently, China Mobile Communications Group Yunnan Co., Ltd. announced that they, in collaboration with China Mobile Research Institute and ZTE Corporation, successfully constructed and were the first to launch a "Tower-Cabinet PV Integrated" green energy microwave photovoltaic station in Hekou Yao Autonomous County, Honghe Hani and Yi Autonomous Prefecture, Yunnan Province.
According to reports, the border region of Honghe Prefecture features high mountains and deep valleys with frequent disasters. Traditional communication site construction models rely heavily on grid power access and optical cable laying, resulting in high infrastructure investment and difficult construction, making it hard to adapt to the deployment needs of complex frontier scenarios.
To address this common challenge, the China Mobile team focused on two main aspects:
Regarding space and cost challenges, the team broke through traditional site construction limitations by pioneering the "Tower-Cabinet PV Integrated" model, directly integrating cabinets into the tower body. This approach maximizes spatial efficiency while significantly reducing infrastructure and operation and maintenance costs.
Regarding the specific networking pain points of "no grid power, no fiber optics," the team created an integrated solution combining "5G Access + PV Power Supply + Lithium Battery Storage + Microwave Backhaul" through multi-dimensional technological innovations.
In this innovative solution, the application of the GaN DC-coupled architecture became a key technical highlight in the energy supply segment.
According to reports, the project team from China Mobile and ZTE achieved a photoelectric conversion efficiency of 23% for high-efficiency PV modules combined with high-precision MPPT PV controllers and a GaN DC-coupled architecture. The peak efficiency of the PV module exceeded 98.5%, realizing direct pure green power supply for communication base stations.
The commercial implementation of this nationwide first "Tower-Cabinet PV Integrated" green energy microwave photovoltaic station is also estimated to be the world's first case of a base station PV MPPT system using GaN power devices. It not only verifies the feasibility and advancement of the GaN DC-coupled architecture in communication base station PV power supply but also provides a replicable and promotable demonstration model for the large-scale commercialization of green energy microwave stations.
2. Harsh Scenarios Prove GaN's Replacement Advantages, Unlocking the Undervalued Incremental Market of "Information Energy"
Regarding the commercial landing of the nationwide first "Tower-Cabinet PV Integrated" solution, China Mobile stated that the project, with its minimalist construction mode of "no grid power needed, no optical cables needed," successfully verified the feasibility and economic viability of the solution in frontier scenarios.
China Mobile indicated that their GaN PV base station project in Yunnan provides a standardized solution that can be referenced and promoted for other communication network constructions in similar regions. As a next step, they will collaborate with China Mobile Research Institute and ZTE Corporation to accelerate the replication and promotion of this solution to more frontier areas. This means GaN is opening a critical entry point in the undervalued incremental market of "Communication Energy."
More importantly, the Yunnan project is just an outpost. China Mobile is introducing PV technology into national base station construction projects, and GaN is expected to enter these PV base stations along with them, transforming from a "frontier exception" to a "universal option."
The Yunnan base station is the starting point, frontier replication is the path, and the comprehensive introduction of base station PV represents a larger space. The undervalued incremental market of communication energy is becoming the third pole for GaN worth re-evaluation after consumer fast charging and PV inverters.
For GaN, the commercial adoption by China Mobile and ZTE signifies that GaN device technology and supply chain have matured, and the irreplaceability of GaN design solutions has been successfully verified.
In PV inverters, Maximum Power Point Tracking (MPPT) is the core function determining power generation levels. Because light intensity, temperature, and load are constantly changing, the output power of PV panels varies accordingly. Therefore, MPPT is required to keep the PV system working at the operating point with the highest output power, thereby converting as much sunlight into electrical energy as possible.
The core components of MPPT consist of voltage-current sampling circuits, MPPT algorithm controllers, and DC-DC converters. China Mobile used low-voltage GaN power devices in the DC-DC stage, replacing traditional silicon MOSFET devices.
In frontier base station PV systems, GaN offers replacement advantages over silicon devices.
First, overwhelming efficiency advantage at high switching frequencies.
According to relevant materials from China Mobile, the PV system using GaN MPPT achieves a component photoelectric conversion efficiency of approximately 23%, with the MPPT module's peak conversion efficiency exceeding 98.5%. Base stations require uninterrupted operation 24/7. Moreover, the power consumption of a single 5G station is about three times that of 4G, and the number of base stations required to cover the same area is also about three times that of 4G. Against the backdrop of a massive base station count, every one-percentage-point increase in conversion efficiency amplifies the marginal benefit of absolute electricity savings.
Second, high power density meets the strict demand for miniaturization.
China Mobile's "Tower-Cabinet PV Integrated" model directly integrates cabinets into the tower body, imposing far higher requirements on the volume and heat dissipation of power conversion modules compared to ground-based PV stations. The high-frequency characteristics of GaN can significantly reduce the size of magnetic components and capacitors, solving the pain point of limited space in base station scenarios. Under equivalent efficiency conditions, this is difficult to achieve with silicon devices.
According to Innoscience, traditional silicon devices are limited to frequencies below 100kHz due to switching losses, requiring numerous input/output capacitors and magnetic components, leading to larger MPPT volumes. In contrast, GaN devices' low switching loss and absence of reverse recovery loss advantages allow switching frequencies to increase by 3-4 times. Solutions developed by them with partners have proven to reduce capacitor quantity by 50% and shrink the overall MPPT equipment volume by more than 50%. Additionally, GaN can reduce the volume and cost of MPPT heatsinks, facilitating equipment lightweighting.
3. Who is Positioning Themselves in GaN PV MPPT?
In the PV MPPT track, GaN power devices are moving from "optional" to "mandatory," with industrial chain companies accelerating positioning around different scenarios.
According to "Hangjiashuo Third-Gen Semi," Innoscience's GaN products have already been successfully applied in household storage and balcony energy storage fields, establishing a first-mover advantage in distributed PV energy storage scenarios.
Based on public information, Infineon has supplied 100V GaN switching devices to BRC Solar GmbH for module-level power optimizer integration, targeting the refined needs of module-level MPPT.
EPC's enhancement-mode GaN power transistors have secured a partnership with Austrian balcony PV manufacturer Efficient Energy Technology (EET), used in the latter's SolMate MPPT product.
Nanosemi chose to collaborate with MCU manufacturers. They jointly launched a 500W single-stage PV micro-inverter solution with GigaDevice Semiconductor, demonstrating the system value of GaN in PV micro-inverters through a single-stage architecture.
In summary, from household storage and balcony energy storage to module-level optimizers, PV micro-inverters, and communication base station energy architectures, the positioning battle for GaN in PV MPPT has fully unfolded.