BIOFUELS

Biofuel is any fuel that is derived from biomass. Biomass in the context of energy production is matter from recently living organisms which is used for bioenergy production. Examples of biomass may include wood, wood residues, energy crops, agricultural residues including straw and organic waste, such as manure from animals, like cow, goats, humans etc.

Also fuel from biomass or biofuels refers to the chemical energy stored within plants by photosynthesis, which theoretically is about 6 to 7% of the solar radiation or energy absorbed or input on land. Biomass in general, is of a lower calorific value than coal, petroleum or natural gas.

The common types of biofuels include; ethanol which is derived mainly from corn, sugarcane or switch grass, biodiesel from vegetable oil or animal fats, biogas from the anaerobic digestion of organic  waste and advanced biofuels from non-food biomass such as agricultural waste or algae.

Biofuels are typically classified into different generations based on their feedstock, production process and environmental impact.

First generation biofuels are produced from food crops, like corn, sugar cane and soybeans. Ethanol is produced widely from corn and sugarcane, while biodiesel is produced mostly from soybeans.

Second generation biofuels are produced from a  wide range of feedstock, which are mainly nonfood crops, like agricultural waste, forestry residue and other waste food products. These non-food feed stocks are rich in lignin and cellulose. Biofuel produced are cellulosic ethanol from switch grass and biodiesel from algae.

The third generation biofuels rely on biotechnology to tweak their cell structure, such that these bio engineered plants are genetically modified  in such a way that the structural building blocks of the cells(ligin, cellulose, hemicellulose)can be managed according to a specific task they are required to perform; for instance trees that grow normally but can be triggered to change the strength of the cell walls so that breaking them down to release sugar is easier, hence resulting in higher yield in the production of ethanol.

Also third generation biodiesel are produced from algae or microorganism. The types of biodiesel produced from this process are algal oil and bio oil from microbial fermentation.

Fourth generation biofuels are produced from genetically modified organisms (GMOs) or synthetic biology. The examples of fuels produced from the process are the microbial fermentation of carbon dioxide into fuels and GMO algae for biofuels.

The fourth generation biofuels are produced from algae, this involves two types of technology; the first involves processing of algae biomass for biofuel production, while the latter or second involves metabolic engineering of algae for producing biofuels from oxygenic photosynthetic microorganism.

Biofuels offer several benefits, including; reduced greenhouse emissions, lower dependence on fossil fuels which are finite, support for rural economies and agriculture and compatibility with existing infrastructure.

However biofuels also have challenges and limitations such as; land use and food versus fuel debates, water and fertilizer requirement, high production costs, energy efficiency and carbon footprint.

Overall, biofuels have the potential to contribute to a more sustainable energy mix, but their development and use must be carefully managed to balance benefits and draw backs.

The future of biofuels is promising with potential growth and advancement in various areas like; the increased focus on non-food biomass and algae, increased or improved efficiency and cost reduction due to primarily in advancement in technology and increasing acceptance due to economic necessity as well as the availability of unused land especially in countries where energy resources like coal, petroleum and gas are unavailable.

 

 

SOURCES.

• Biofuels: policies, standards and technologies, World energy council (c) 2015; world energy council.
• From 1^st to 2^nd generation biofuel technologies by Ralph Sims, Michael Taylor, Jack Saddler and Warren Mabbe.( c )2018; OECD/IEA.
• Biofuels from Algae; edited by Ashok Pandey, Duu-Jong Lee and Jo-Shu Chang.
• Biofuel production from biomass by KatalinBarta and Istvan T. Horvarth.
• Biomass to biofuels; Strategies for global industries by Alain A. Vertes, Nasib Qureshi  and Hans P. Blaschek.