A case for biogas as the viable substitute fuel in spark ignition engines

Abstract: Unstable prices, energy security, depleting reserves and their negative effect on the ecosystem have forced mankind to critically tackle it’s over dependence on fossil fuels. Fossil fuels are oil coal and natural gas which currently caters for over 80% of the world’s energy needs. Crude oil derivatives and coal have been extensively tapped and utilized to make living more comfortable and to drive different sectors that power the world’s economies. These have however come at an irreparable cost on human health and the environment. The transport sector, a major driver of development consumes the 2nd largest portion of our fossil energy reserves and has also been at the forefront of the creation of alternative fuels to mitigate various economic, political and environmental challenges associated with the refining and utilization of the conventional fuels in the sector which are petrol and diesel. The sector recently turned to natural gas as an efficient substitute particularly in the more popular passenger cars that utilize spark ignition engines. It performs excellently with lesser tail pipe emissions when compared with petrol which emits lesser harmful products than diesel. Though readily available, with well-developed infrastructure, its fossil nature makes it a finite resource hence the need for a viable renewable replacement fuel. Many alternative fuels have been developed to power the spark ignition engine as stricter emission standards are being created and the need for improved fuel economy with better system efficiency. This paper highlights the popular alternative fuels been utilized in spark ignition engines which are hydrogen, ethanol, liquefied petroleum gas and biogas looking at criteria such as performance, renewability, ease of integration into existing infrastructure and cost with the need to make a case for biogas as the right substitute for petrol in existing and future spark ignition engine applications