Advantages and Disadvantages of Biofuels

Biofuels are fuels produced from biomass. Chemically, these fuels are usually in the form of alcohols, esters, ethers, etc. They are produced by a number of processes; since there is no method applicable to all biofuels, it would be better to explain each in its own right.

The most obvious point of distinction between biofuels and fossil fuels is that biofuels are synthesized or manufactured using preexisting machinery and raw material, rather than relying on natural and - in the big picture - quite restricted sources.

• Biodiesel
  Biodiesel is made from vegetable oil and rapeseed oil, or it can be formed from previously used cooking oil (unused cooking oil can also be used as a biofuel, albeit in very few applications) and tallow (animal fat),

Which would otherwise be incinerated, put in a landfill or exported. The process used to acquire biodiesel is called transesterification.

• Bioethanol is made from carbohydrate-rich crops such as corn, sugar beet, wheat, potatoes and a variety of other starch 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.

Various other biofuels are gaining in popularity, and significant research on the same is currently a much-coveted technological acquisition. Some examples of these biofuels include algal fuel, which is derived from the oil produced by algae, biogas, jatropha oil, etc.

Several groups have championed biofuels as the best option to fossil fuels, but is that really the case? Let's take a look.

Biofuels are made from crops that can, potentially, be grown in vast quantities and thus carry a much lesser threat of running out than conventional fossil fuels. This also means that biofuels can be produced and utilized on an infinitesimally shorter time scale than fossil fuels, which need millions of years to naturally decompose and form.

Since biofuels are not composed of hydrocarbons, they produce much lower levels of greenhouse gases upon combustion, and thus are much less harmful to the atmosphere. However, they produce more nitrous and nitric oxides (one of the cause of acid rain) than conventional fuels.

Bioethanol and biodiesel can be used in existing automobile designs with no or minimal changes to the engine. Bioethanol is already being used in many countries - particularly Brazil - as an additive or even a substitute to conventional fuel.

Since biofuels are manufactured from a range of crops that can be (and indeed are, in most cases) grown almost universally, each country (or even smaller subdivisions) could potentially become self-reliant in matters of energy demands, ending the hegemony of the likes of OPEC (Organization of the Petroleum Exporting Countries), et al.

The most widely used argument against biofuels is that they would take up harvests of crops that are used as a primary food source all over the world, especially corn. With hunger and malnutrition issues already at the fore of the global conscience, it is worthwhile to debate whether the bigger need is to fuel or to feed.

While it is, without doubt, true that biofuels emit less greenhouse gases than fossil fuels, the machinery required for the production, transport and other such treatments performed on the biofuel is run on fossil fuels, negating the positive effect the produced biofuels would go on to have.

Unless the necessary infrastructure is constructed in order to make the machinery run on biofuel, the net greenhouse impact of biofuels would continue to hover around nil.

Corn, which is the primary crop used in the production of biofuels, may well go on to become an environmentally friendly fuel - albeit with the basic drawbacks explained in the previous point - but the energy and resources required to raise a crop of corn are considerable, to say the least.

The water used in the production of corn puts undue pressure on the concerned water source and may lead to water shortage in the surrounding communities. Pesticides, most of which are chemical, are known to cause irreparable damage to the soil, and eventually the water source they flow into.

More corn is grown annually than any other grain in the world - more than 800 million tons. Massive amounts of water and pesticides, for a start, are required to sustain (or increase by the smallest degree) such a large figure.

Currently, biofuels fulfill less than 3% of global fuel usage. If biofuels were to be given a more prominent role in global fuel dynamics, it would either require massively fertile and productive hybrid species of crops such as corn, jatropha, switchgrass, etc.

(which seems a long shot, going by current standards), or an exponential increase in the area of cultivation of these crops. Then comes riding into the equation the world's population, which is expected to rise to 10-13 billion by the dawn of the 22nd century.

Taking into account the increased need of space for human habitation, and the corresponding increase in the demand for fuel, it would be safe bet to estimate that the world's forests would be the component bearing the brunt of the escalated circumstances; rainforests have already started to make way for commercial crops in many countries, especially in Asia.

The accelerated rate of deforestation would lead to a plethora of already-well-publicized problems.

An Alternative?
One biofuel that deserves a distinct mention is algal fuel. A growing community of scientists and investors believe that algal fuel can be produced while bypassing the hurdles listed above.

√ Algae would not intrude on land reserved for food crops, since they can also grow in wastelands, swamps, etc.

√ Similarly, resources reserved for agricultural purposes would not be hijacked by algae, which, of course, do not require external stimulants, fertilizers, or pesticides.

√ Algae, like fossil fuels, emit CO2 when burnt. However, CO2 adds to the environmental amount, since the biomass responsible for it has already been fossilized (and converted to crude oil). Since algae would only be utilized in biofuel production in fragments, the resultant CO2 would be absorbed by the remaining 'algal field'.

It is tricky to conclusively pick a side in the debate on biofuels; while it is true that the fossil fuel reserves are depleting by the minute and the world is desperately in need of an alternative, it is also true that widespread use and optimum utilization of biofuels would necessitate infrastructural and technological upgrades upon the existing method.