. Introduction
Increasing interest in the use of renewable energy resources has stimulated many initiatives adopting the use of renewable energy in the public sector. Biogas in particular is perceived in a positive light as the feedstock in its production is often considered waste from other industries, such as livestock manure or household organic waste. Furthermore, biogas can be used in existing infrastructure for natural gas it is upgraded to remove the CO2 and H2S fractions, thereby removing the need to build and purchase specialized equipment