New Delhi, Jan. 2 -- Homegrown carmakers JSW Motors and Mahindra & Mahindra (M&M) are open to adopting range-extended electric vehicles (REEVs) if India's policy framework expands incentives beyond pure electric vehicles, even as experts warn against equating the technology with battery-electric cars.

REEVs, also called REX (range extender) hybrids, are always driven by an electric motor but carry a small internal combustion engine (ICE) whose sole role is to generate electricity when the battery charge runs low. Comparatively, strong hybrids have both an electric battery and a powerful ICE engine, both of which can run the vehicle.

To be sure, no carmaker in India manufactures or sells REEVs currently. Strong hybrid vehicles are on off...