Biogas for fuel or electricity?

Biogas is a natural product of biological activities in the absence of oxygen. This gas is composed mainly of methane (natural gas) and carbon dioxide and traces of other gases such as hydrogen sulfite. The biogas is produced almost all around the world naturally or under controlled condition. The major applications of biogas are for heating, cooking, electricity production and car fuel. While many other countries are interested to electricity, Sweden is investing more and more on biogas as fuel for cars, buses and trucks. Here in Borås, we have 59 city buses all run only on biogas (no diesel and no gasoline). In order to make the fuel from raw biogas, we just have to separate CO2 and other gases (water scrubbing) to get at least 97% methane purity and also dry the gas from water vapor. A simple process for this purification is just washing the gas with water (to dissolve CO2) and then pass it through zeolite to dry it. It is a simple process to convert the wastes to a fuel for your car!



(A water scrubbing unit to purify methane in raw biogas. The unit is located in Trollhättan in Sweden)