e-NRG bioethanol is a high-quality, clean-burning fuel specifically formulated for use in liquid ethanol-fuelled ventless fireplaces. Also known as denatured alcohol or ethanol, bioethanol is a naturally derived fuel made from fermented plant sugars. e-NRG is the only brand of bioethanol that has been tested with and recommended for use in EcoSmart Fire burners. The burning of this fuel creates nothing more than heat, water vapour and carbon dioxide – a cleaner heating solution for you and the environment.