Ultra-Efficient Natural Gas-Diesel Hybrid Engine (IMAGE) ETH Zurich Caption ETH researchers redesigned the conventional diesel engine of a VW Golf to run on 90 percent natural gas. Credit Tobias Ott / ETH Zurich Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.