China Commissions First Hydrogen-Powered Zero-Carbon Energy Center for Metro Depot

China's first hydrogen-powered zero-carbon smart energy center for a metro depot has entered operation at the Xiliu Metro Depot in Xi'an High-tech Zone following the successful completion of trial operations.

Built by China State Construction Sixth Engineering Bureau Investment & Transportation Co., Ltd., the project replaces the traditional single-source electricity supply model for rail transit depots with an integrated energy system combining photovoltaic (PV) generation, battery energy storage, hydrogen energy and geothermal heating.

Covering approximately 71,000 square meters, the energy center consists of an energy management hub, a hydrogen station, a photovoltaic system, a battery energy storage station and a ground-source heat pump system. It provides electricity, heating and cooling services for the entire depot, including a 118,900-square-meter heating area.

The project makes full use of available space and energy resources across the depot. A 7 MW distributed rooftop photovoltaic system is expected to generate approximately 7.7 million kWh of electricity annually, supplying much of the depot's daily energy demand. A large-capacity smart battery storage system stores excess solar power during peak generation periods and releases electricity when needed, helping balance fluctuations in renewable power output.

The project also features China's first depot-scale hydrogen energy station integrating green hydrogen storage and power generation. Designed to support deep decarbonization of rail transit infrastructure, the system complements photovoltaic, battery storage and geothermal energy to improve overall energy resilience and flexibility.

Geothermal energy is supplied through six medium-deep wells reaching 2,700 meters and more than 480 shallow ground heat exchange wells, providing stable heating and cooling throughout the depot. Together, the photovoltaic, battery storage, hydrogen and geothermal systems operate as an integrated energy network, delivering a reliable year-round zero-carbon energy supply.

The facility is equipped with a self-developed digital twin platform and AI-based energy management system that provides real-time monitoring, optimization and visualization of the entire energy system.