syngas

Syngas, or synthesis gas, is a fuel gas mixture consisting primarily of hydrogen, carbon monoxide, and very often some carbon dioxide. The name comes from its use as intermediates in creating synthetic natural gas (SNG) and for producing ammonia or methanol. Syngas is usually a product of  gasification and the main application is electricity generation. Syngas is combustible and often used as a fuel of internal combustion engines. It has less than half the energy density of natural gas.