Question

write an essay on topic
Biofuel - need of hour

Answer 1

Importance of biofuels

World demand for energy has been projected to double by 2050 and be more than triple by the end of the century. Since industrial revolution in the 1850s, the human consumption of fossil fuels has been one of the growing causes of international concern and unease among some industrial nations. The reasons for which can be attributed to the rapidly depleting reserves of fossil fuels. Over the past few decades, with the successes achieved in genetic engineering technology, advances made in the field of biofuels offer the only immediate solution to fossil fuels.

Presently, most of the ethanol in use is produced either from starch or sugar, but these sources have not proven to be sufficient to meet the growing global fuel requirements. However, conversion of abundant and renewable cellulosic biomass into alternative sources of energy seems to be an effective and promising solution. But for this technology to become viable there is a need to develop cheap and sustainable sources of cellulases along with eliminating the need for pretreatment process.The review thus aims to provide a brief overview about the need and importance of biofuels particularly bioethanol with respect to the growing environmental concerns along with an urgent need to address the existing problems about cost-optimisation and large scale production of biofuels.

1.0 Introduction

Biofuels are liquid fuels derived from plants. Currently, first generation biofuels are extensively being produced and used. These are generated using starch, sugar, vegetable oils and animal fats using fairly expensive conventional technology. In recent years, the fact that production of ethanol from cellulosic and lignocellulosic material is being hindered due to inadequate technology to enable efficient and economically viable methods to break down the multipolymeric raw material has gained wide popularity (Verma et al, 2010). Therefore, there is a need to develop efficient systems for the production of cellulases and other cellulose degrading enzymes. Lignocellulosic biofuels are thus likely to be seen as a part of the portfolio of solutions being offered to reduce high energy prices, including more efficient energy use along with the use of other alternative fuels (Coyle, 2007).

1.1 Importance of biofuels:

Factors like the finite petroleum reserves and constantly rising demands for energy by the industrialised as well as the highly populated countries (on their Way to industrialisation) like India and china have made it absolutely necessary to look into alternate and efficient methods to replace these fuels in future (Stephanopoulos, 2008). Also, concerns like steep rise in fossil fuel prices in the recent years, increasing concerns about climate change like global warming, insecurity and unrest among governments due to their depleting natural reserves are just a few factors that define an urgent need for a sustainable path towards renewable fuel technology development (Stephanopoulos, 2008). Among the various types of alternative fuels considered (liquid fuels from coal and/or biomass with and without carbon capture and storage (CCS)), biofuels derived from lignocellulosic biomass offer the most clean and sustainable alternative to fossil fuels essentially because of their cost competitiveness as opposed to the current expensive methods of ethanol production from sugarcane and corn (Stephanopoulos, 2008) (Shen and Gnanakaran, 2009).

The global production and use of biofuels has increased tremendously in recent years, from 18.2 billion litres in 2000 to about 60.6 billion litres in 2007. It has been estimated that about 85% of this amount is bioethanol (Coyle, 2007). This increase is primarily a result of the reasons stated above along with rising concerns about global warming and greenhouse gas emissions due to excessive fossil fuels usage since biofuels are carbon-neutral and reduce green house emissions (Sainz, 2009). Also, one of the factors contributing to the viability of biofuels as an alternative transportation fuel is their ease of compatibility with our existing liquid fuel infrastructure (Sainz, 2009).

An important step in the production of biofuels is the breakdown of cellulose fibres by the enzymes capable of degrading it. But the production of these enzymes is still an expensive task due to their production in large microorganism bioreactors. One method for the inexpensive production of these enzymes is the use of transgenic plants as heterologous protein production systems (Danna, 2001; Kusnadi et al., 1997; Twyman et al., 2003). Plant based enzyme production offers advantages over the traditional bacterial and fungal cultures by being commercially viable and particularly attractive since in plants, the desired protein can be made to accumulate at high levels i