A carbon fiber metro train, dubbed CETROVO 1.0, began passenger service on Friday in the port city of Qingdao in east China's Shandong Province.

This metro train features a carbon fiber composite body and frame, which reduces the weight of the car body and bogie frame by 25 percent and 50 percent, respectively, making the total vehicle weight 11 percent lighter compared with conventional trains.

Liu Jinzhu, chief designer of the train with CRRC Qingdao Sifang Co., Ltd., said the energy consumption of each train can be reduced by 7 percent during operation, leading to an annual drop of about 130 tonnes in carbon dioxide emissions -- which is roughly the same as planting 101 mu (around 6.7 hectares) of trees.

Notably, the use of carbon fiber materials also reinforces the vehicle's body, boosts its impact resistance and extends the durability of its structure.

The interior of this train's cabin is rich in carbon fiber elements, ranging from sleek black carbon fiber seats and armrests to the driver's console -- all contributing to a futuristic, high-tech feel. Thanks to the use of carbon fiber composites, the vehicle also boasts enhanced vibration damping and sound isolation, ensuring a smoother ride and a more comfortable experience for passengers.

In addition, a digital twin-based intelligent maintenance platform, SmartCare, has been developed for the carbon fiber train. This platform enables smart fault detection, real-time health monitoring and maintenance optimization -- thereby reducing overall repair costs.