Biogas is an alternative fuel for powering vehicles and is a very real alternative to petrol and diesel. Biogas is a mix mainly of methane and carbon dioxide and is produced naturally when organic matter decomposes in the absence of oxygen. There are effectively two ways to come by this fuel, either from landfill sites or through anaerobic digestion.
Landfill sites produce biogas when the waste is subjected to anaerobic microbiological action. This can leak into the atmosphere but it is possible to drill into a landfill site in order to extract the biogas for some form of power generation. This ensures the continued safety of the site after landfilling is finished and is also an income source.
Alternatively, biogas can be produced by emulating this process through anaerobic digestion. This accelerates the natural process of the landfill site and is typically used on wet wastes such as sewage sludge or animal slurries.
As well as being used to generate power, biogas can also be used as a vehicle fuel. Compared to diesel this has an average 95% reduction from ‘well to wheel’ of carbon dioxide emissions, an 80% reduction in nitrous oxide emissions and zero particulate emissions. In fact, it is suggested that carbon emissions are reduced by over 100% because the organic waste used to make the fuel would otherwise emit methane into the atmosphere.
To invest in a biogas-fuelled vehicle is initially expensive with a HGV costing £25,000 to £35,000 more than its diesel equivalent. The fuel is, however, cheap to produce and subject to lower tax than traditional fuels. In the UK at present there is a limited refuelling network but several refuelling stations linked to the HGV industry are planned over the next five years.
Thinking of converting to an alternative fuel? Take a look at our step by step Alternative Fuel Conversion guide.
