Advantages and Disadvantages of Biofuels

As environmental consciousness is increasing, more and more vehicle drivers are turning to biofuels.

What are Biofuels?

Biofuels are combustible fuel produced from biomass. These fuels are usually in the form of alcohols, esters, ethers, and other chemicals produced from biomass. The two main biofuels are biodiesel and bioethanol.

How is biodiesel made?

It is made from vegetable oil and rapeseed oil, or it can be converted from used cooking oil and tallow (animal fat), which would otherwise be incinerated, put in a landfill or exported.

How is bioethanol made?

It is made from carbohydrate crops such as maize, sugar beet, wheat, potatoes and a variety of other starch and sugar crops. Bioethanol can also be derived from cellulose found in common vegetation ("cellulosic ethanol"). For instance, in the USA, attempts are being made to extract bioethanol from switchgrass, which grows 12feet tall. Henry Ford's Model T car was originally designed to run on ethanol.

Disadvantages of Biofuels

• Growing crops for biofuel absorbs the carbon that biofuels emit, but it does not absorb the fossil fuel emissions created in planting, fertilizing, treating, harvesting, transporting and processing these crops before they can be converted into fuel. There are also considerable carbon emissions from the coal or gas required to heat the required raw materials in the manufacturing process. Its production can also lead to environmental destruction. Brazil, for example, produces ethanol from sugar cane but to do so is cutting down the Amazon rain forest, thus causing great damage to the environment.
• Too much concentration on running vehicles on plant oil would set up a direct competition between feeding the cars and feeding the people. This would not increase our self-reliance but would increase our food and energy vulnerability.

Advantages of Biodiesel

• It is made from renewable resources.
• It performs just as well as the normal diesel fuel.
• It causes less pollution as compared to diesel-powered engines.
• It is relatively less inflammable compared to the normal diesel.
• It can be mixed with normal diesel fuel.
• It is biologically degradable and reduces the danger of contamination of soil and underground water during transport, storage and use.
• It contains no sulphur, the element responsible for acid rain.
• There are no extra costs for the conversion of engines in comparison to other biological fuels.
• It is suitable for catalytic convertor.
• Engines last longer when using it.
• Its refineries are comparitively simpler and environmental-friendly in design than typical petrochemical refineries.
• It produces 78% less carbon dioxide (CO2) than normal diesel fuel.
• It has a higher cetane and lubricity rating than pure petroleum-based diesel fuel, which improves engine efficiency and operating life cycle.

Disadvantages of Biodiesel

• It is more expensive than normal diesel fuel.
• It tends to reduce fuel economy.
• It is less suitable for use in low temperatures.
• It cannot be transported in pipelines.
• It gives out more nitrogen oxide emissions.
• Only a few petrol stations offer biodiesel-fuel.
• It can only be used in diesel-powered engines.
• It can cause inner fuel tubes of older vehicles to lose their long-lasting qualities.
• It is more likely than petroleum diesel to attract moisture, which can cause problems in cold weather (fuel freezing, deposit of water in the vehicle fuel delivery system, fuel cold flow, clouding, and an increased corrosion, for example) and increase the risk of microbial growth (which can also clog engine filters).

Advantages of Bioethanol

• The use of ethanol-blended fuels such as E85 (85% ethanol and 15% gasoline) can reduce the net emissions of greenhouse gases by as much as 37.1%, which is a significant amount.
• Ethanol-blended fuel as E10 (10% ethanol and 90% gasoline) reduces greenhouse gases by up to 3.9%.
• The net effect of ethanol use results in an overall decrease in ozone formation, an important environmental issue. (The emissions produced by burning ethanol are less reactive with sunlight than those produced by burning gasoline, which results in a lower potential for forming the damaging ozone).
• Ethanol is considered a renewable energy resource because it is primarily the result of conversion of the sun's energy into usable energy. Creation of ethanol starts with photosynthesis, which causes feedstocks, such as sugar cane, to grow. These particular feedstocks are processed into ethanol.
• It benefits energy security as it shifts the need for some foreign-produced oil to domestically-produced energy sources.
• It reduces greenhouse gases.
• It burns more cleanly (more complete combustion).
• It reduces the amount of high-octane additives.
• The fuel spills are more easily biodegraded or diluted to non toxic concentrations.

Disadvantages of Bioethanol

• Production of ethanol requires significant energy and large amounts of land.
• Fuels with more than 10% ethanol content are not compatible with non E85-ready fuel system components and may cause corrosion of ferrous components.
• It can negatively affect electric fuel pumps by increasing internal wear and undesirable spark generation.
• It is not compatible with capacitance fuel level gauging indicators and may result in erroneous fuel quantity indications in vehicles that employ that system.