A subsidiary of Chinese automaker Changan Automobile is developing a detachable range extender designed to provide additional power for battery-electric vehicles when needed.
Hunan Tianyan said it is working on a retrofittable Power Turbine Generator (PTG), a compact auxiliary power system that combines a small gas turbine, generator and power electronics to supply electricity to electric vehicles.
The company said the system is intended to address situations where EV drivers may experience reduced range, such as in low temperatures, during high-speed motorway driving or when charging infrastructure is limited.
Unlike integrated range extender systems commonly used in extended-range electric vehicles (EREVs), the PTG concept is designed as a detachable module that could be attached to battery-electric vehicles when additional energy supply is required.
According to Hunan Tianyan, the PTG functions as a modular auxiliary power source capable of providing electricity on demand and extending the overall driving range of an electric vehicle.
The company has not yet disclosed key technical specifications or performance figures, and the concept has not been presented as a production-ready product. So far, the company has only released a test-bench image of the system through social media.
Details about how the module would physically integrate with battery-electric vehicles also remain unclear. In the broader industry, some suppliers have begun developing compact "drop-in" range extender modules designed to be integrated into electric vehicle platforms with minimal modifications, allowing automakers to offer both BEV and EREV versions.
Hunan Tianyan said engineers encountered several technical challenges during development of the PTG system, particularly related to efficiency and thermal management.
The company said it developed "a high-efficiency ball bearing system, a high-efficiency bladed compressor, and a turbine with fixed guide vanes," which reportedly increased efficiency by more than 5%.
Engineers also addressed thermal loads generated by the gas turbine within the compact system by designing "an innovative high-efficiency cooling channel structure" and implementing a heat management strategy based on detailed thermal flow simulations.
According to the company, the next stage of the project will focus on advancing the technology toward industrialisation.
Hunan Tianyan said the aim is to bring "a freer, more convenient and sustainable travel experience to new energy vehicle users," while supporting the development of China's advanced equipment manufacturing sector.