Biofuels- Different Categories, Advantages & Disadvantages

Biofuels- Different Categories, Advantages & Disadvantages

Biofuels- Different Categories, Advantages & Disadvantages

What are Biofuels?

  • Any hydrocarbon fuel that is produced from an organic matter (living or once living material) in a short period of time (days, weeks, or even months) is considered a biofuel.
  • Biofuels may be solid, liquid, or gaseous in nature.
    • Solid: Wood, dried plant material, and manure
    • Liquid: Bioethanol and Biodiesel
    • Gaseous: Biogas
  • These can be used to replace or can be used in addition to diesel, petrol, or other fossil fuels for transport, stationary, portable, and other applications. Also, they can be used to generate heat and electricity.
  • Some of the main reasons for shifting to biofuels are the rising prices of oil, the emission of greenhouse gases from fossil fuels, and the interest in obtaining fuel from agricultural crops for the benefit of farmers.

What are the Different Categories of Biofuels?

  • First Generation Biofuels:
    • These are made from conventional technology and are made from food sources such as sugar, starch, vegetable oil, or animal fats.
    • Common first-generation biofuels include Bioalcohols, Biodiesel, Vegetable oil, Bioethers, and Biogas.
    • Though the process of conversion is easy, the use of food sources in the production of biofuels creates an imbalance in the food economy, leading to increased food prices and hunger.
  • Second Generation Biofuels:
    • These are produced from non-food crops or portions of food crops that are not edible and considered as wastes, e.g., stems, husks, wood chips, fruit skins, and peeling.
    • Examples include cellulose ethanol and biodiesel.
    • Thermochemical reactions or biochemical conversion processes are used to produce such fuels.
    • Though these fuels do not affect the food economy, their production is quite complicated.
    • Also, it is reported that these biofuels emit fewer greenhouse gases than first-generation biofuels.
  • Third Generation Biofuels:
    • These are produced from micro-organisms like algae.
    • Example- Butanol
    • Microorganisms like algae can be grown using land and water that are unsuitable for food production, therefore reducing the strain on already depleted water sources.
    • One disadvantage is that fertilizers used in the production of such crops lead to environmental pollution.
  • Fourth Generation Biofuels:
    • In the production of these fuels, crops that are genetically engineered to take in high amounts of carbon are grown and harvested as biomass.
    • The crops are then converted into fuel using second generation techniques.
    • The fuel is pre-combusted, and the carbon is captured. Then the carbon is geo-sequestered, meaning that the carbon is stored in depleted oil or gas fields or in unmineable coal seams.
    • Some of these fuels are considered carbon-negative as their production pulls out carbon from the environment.
Major Types of Biofuels
BioethanolIt is derived from corn and sugarcane using fermentation process. A litre of ethanol contains approximately two thirds of the energy provided by a litre of petrol. When mixed with petrol, it improves combustion performance and lowers the emissions of carbon monoxide and sulphur oxide.
BiodieselIt is derived from vegetable oils like soybean oil or palm oil, vegetable waste oils, and animal fats by a biochemical process called “Transesterification.” It produces very less or no amount of harmful gases as compared to diesel. It can be used as an alternative for to conventional diesel fuel.
BiogasIt is produced by anaerobic decomposition of organic matter like sewage from animals and humans. Major proportions of biogas are methane and carbon dioxide, though it also has small proportions of hydrogen sulfide, hydrogen, carbon monoxide and siloxanes. It is commonly used for heating, electricity and for automobiles.
BiobutanolIt is produced in the same way as bioethanol, i.e., through the fermentation of starch. The energy content in butanol is the highest among the other gasoline alternatives. It can be added to diesel to reduce emissions. It serves as a solvent in textile industry and is also used as a base in perfumes.
BiohydrogenBiohydrogen, like biogas, can be produced using a number of processes such as pyrolysis, gasification or biological fermentation. It can be the perfect alternative for fossil fuel.

What are the Advantages of Biofuels?

  • Availability: Biofuels are produced from biomass and thus are renewable.
  • Source Material: Whereas oil is a limited resource that comes from specific materials, biofuels can be manufactured from a wide range of materials including crop waste, manure, and other byproducts.
  • Environment Pollution: Biofuels do not release as much carbon as fossil fuels do but fertilizers that are used in the growing biofuels lead to greenhouse emissions. Also, biofuels can help in managing municipal solid wastes i.e., the waste can be converted into fuel.
  • Security: Biofuels can be produced locally, which decreases the nation’s dependence upon foreign energy. By reducing dependence on foreign fuel sources, countries can protect the integrity of their energy resources and make them safe from outside influences.
  • Economic Stimulation: Because biofuels are produced locally, biofuel manufacturing plants can employ hundreds or thousands of workers, creating new jobs in rural areas. Biofuel production will also increase the demand for suitable biofuel crops, providing economic stimulation to the agriculture industry.

What are the Disadvantages of Biofuels?

  • Efficiency: Fossil Fuels produce more energy than some of the biofuels. For example, 1 gallon of ethanol produces less energy than 1 gallon of gasoline (a fossil fuel).
  • Cost: Pumping fossil fuels from the ground is a difficult and expensive process leading to high costs. Production of biofuels requires land, this impacts cost of biofuels as well as that of food crops. Also, though growing engineered biofuel crops can benefit farmers commercially but the excess number of such crops can also lead to loss of biodiversity.
  • Food Shortages: There is concern that using valuable cropland to grow fuel crops could have an impact on the cost of food and could possibly lead to food shortages.
  • Water Use: Massive quantities of water are required for proper irrigation of biofuel crops as well as to manufacture the fuel, which could strain local and regional water resources.

International Initiatives on Sustainable Biofuels

Production of sustainable biofuels is required to reduce their impact on the environment and economy.

Roundtable on Sustainable Biomaterials (RSB)

  • It is an international initiative that brings together farmers, companies, governments, non-governmental organisations, and scientists who are interested in the sustainability of biofuel production and distribution.
  • In April 2011, it launched a set of comprehensive sustainability criteria – the “RSB Certification System.” Biofuels producers that meet these criteria are able to show buyers and regulators that their product has been obtained without harming the environment or violating human rights.

Sustainable Biofuels Consensus

It is an international initiative which calls upon governments, the private sector, and other stakeholders to take decisive action to ensure the sustainable trade, production, and use of biofuels.

Bonsucro

  • It is an international not for-profit, multi-stakeholder organization established in 2008 to promote sustainable sugar cane.
  • Its stated aim is to reduce ‘the environmental and social impacts of sugarcane production while recognising the need for economic viability’.
  • It does that through setting sustainability standards and certifying sugar cane products including ethanol, sugar and molasses.

National Policy on Biofuels, 2018

  • The Policy categorises biofuels as “Basic Biofuels” viz. First Generation (1G) bioethanol & biodiesel and “Advanced Biofuels” – Second Generation (2G) ethanol, Municipal Solid Waste (MSW) to drop-in fuels, Third Generation (3G) biofuels, bio-CNG etc. to enable extension of appropriate financial and fiscal incentives under each category.
  • It expands the scope of raw material for ethanol production by allowing use of sugarcane juice, sugar containing materials like sugar beet, sweet sorghum, starch containing materials like corn, cassava, damaged food grains like wheat, broken rice, rotten potatoes, unfit for human consumption for ethanol production.
  • The Policy allows use of surplus food grains for production of ethanol for blending with petrol with the approval of National Biofuel Coordination Committee.
  • With a thrust on Advanced Biofuels, the Policy indicates a viability gap funding scheme for 2G ethanol Bio refineries of Rs.5000 crore in 6 years in addition to additional tax incentives, higher purchase price as compared to 1G biofuels.
  • The Policy encourages setting up of supply chain mechanisms for biodiesel production from non-edible oilseeds, Used Cooking Oil, short gestation crops.
  • Roles and responsibilities of all the concerned Ministries/Departments concerned with respect to biofuels have also been captured in the Policy.

Related Links:

Global Biofuel AllianceCarbon Border Adjustment Mechanism
National Quantum MissionGOBAR Dhan Scheme

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