Liquid biofuels are extracted from biomass. They possess a high potential of reducing the emission of greenhouse gases by substituting the usage of fossil fuels.
Countries around the globe are increasingly considering the use of liquid biofuels as an alternative to fossil fuel in the transport sector. The idea is to ensure the reduction of GHG emissions. Countries also wish to cut down on their dependency on fossil fuels, which are imported.
Liquid biofuels are a constituent part of bioenergy. It is a modern use of traditional biomass. The related issues in the use of liquid biofuels are the following.
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Research studies suggest that biofuels as a whole are capable of offering a low-carbon option and a sustainable alternative to the existent petroleum fuels. The word of caution is that appropriate policy measures need to be put in place to ensure the sustainability factor.
Reports state that new technological developments in this field need to be customized to local conditions.
Another issue which needs examination regarding the use of liquid biofuels is its impact on biodiversity of a concerned region.
Use of liquid biofuels on a broad scale entails its commercial production. Now the fact is that the arena of biofuels is substantially complex. There exist a variety of combination of feedstocks, end-use applications and conversion routes for liquid biofuel production.
Of them some options have already reached a commercially viable stage of production. Still others are in the R&D stage.
Regarding the use of liquid biofuels for transport purpose, Brazil's use of ethanol (sourced from sugarcane) as automobile fuel is commendable. Many developing nations are set to follow Brazil's footsteps in this regard.
Use of liquid biofuels should be done in a sustainable way. Its mode of production needs to iron out any negative impact(s) on biodiversity, soil and water. The issue of food security also needs to be accorded prime importance.
It has been observed that the use of liquid biofuels belonging to the first generation yield modest returns compared to the newer variety. It may be noted that the first generation liquid biofuels are mostly seed based or grain based.
It has been estimated that under favorable conditions coupled with the full use of co- products and high yields the use of plant-oil based biodiesel can lead to up to 65% GHG reductions (in comparison to the fossil diesel).
Among the commercial varieties of liquid biofuels available today, topmost efficiency in land use for GHG mitigation is provided by sugarcane ethanol.
With the existence of proper sustainable safeguards (in production) sugarcane ethanol can potentially provides upto 90 percent of GHG emissions reduction (in comparison with fossil fuels). They also come cheaper.
Use of Biodiesel sourced from palm oil is a relatively cheaper option. However its GHG balance appears to less favorable than sugarcane ethanol.
It may be noted that most 2nd generation liquid biofuels are in R&D stage. They are mostly being sourced from non-food biomass like perennial grasses, wastes, wood and residues.