How Hydrogen-Enriched Natural Gas Can Cut Carbon Emissions (image) Swansea University Share Print E-Mail Caption H2 (hydrogen as a gas) combined with CH4 (methane) produces hydrogen-enriched natural gas (HENG). This can help lower carbon emissions (CO2). Credit Swansea University Usage Restrictions None Share Print E-Mail 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.