Meanwhile planned rules on emissions of pollutants like nitrogen oxides could increase the cost of producing these cars. LONDON/BRUSSELS, April 12 (Reuters) - Remember when plug-in hybrid cars were the go-to technology for the climate-conscious driver? Turns out, they’re not good for the environment, according to some experts, and they could be phased out by carmakers in the face of tougher European rules.ĮU policy plans for plug-in hybrid vehicles (PHEVs), which contain an electric battery and a combustion engine, could mean the 'transition' technology has a shorter lifespan than envisaged by some leading automakers.ĭraft green finance regulations would ban manufacturers from labelling them as 'sustainable investments' beyond 2025, potentially deterring investors.