The traditional biofuels are being made from editable substances such as corn, mustard, sugarcane which creates a shortage in the food supply in many parts of the world.
The development is underway to produce the second generation of biofuels from in-editable substances like grass (lignocellulosic), paper, wood, stalks, etc. The third generation biofuels come from algae, that are low-input, high-yield feedstock to produce Biofuels.
Today, the world is facing the energy crisis due to higher fuel consumption rate, thanks to increasing in population, and fluctuating energy prices result in inclination towards sustainable energy sources mainly from solar, wind, and biofuels.
Biofuels are fossil fuel substitutes that can be made from a range of agricultural crops and other sources of biomass. The two most common current Biofuels are ethanol and biodiesel.
Why Biofuels have become a key issue?
Some of the critical reasons for going with biofuels are energy security (increasing oil prices, need for an alternative source of energy), to decrease greenhouse gas emission, and to promote rural development.
Biofuel is derived from farm produce and presently many countries allow using biofuel of some percentages in petrol and diesel. The grains include maize, mustard, soybean; sugarcane, etc. are used to make biofuels. Since these crops became cash crops and started earning huge revenue, in short time, there was a shortage of food in many countries and prices started rising that resulted in many controversies against biofuels.
In order to grow biofuel crops, the countries started buying land from poor countries and leasing them. In this way, new colonialism was born that got into the world’s biggest energy crisis. This is the first generation of biofuel conditions suffered a lot to its own success.
In the story of climate change and energy security, food crops used to fill fuels instead of filling people’s tanks resulted in no change in food prices, but there was a dramatic change in use of land. More land was allotted to those crops which could be obtained from biofuel, whereas on the other hand, the land was reduced to several pulses, dal, wheat, sorghum, millet, and rice.
Current efforts are being made across the globe for developing and integrating the resources, technologies, and systems across the supply chain needed to grow a biofuels industry in a way that protects the environment.
|Biofuels Life-cycle (Image source: NREL)
Now, it’s time to explore the second generation of biofuels with focused on science and technology. You must be confused with the term, ‘What is the second generation of biofuels?”. Biofuel sources in the second generation are about to develop a biofuel system from the waste of food crops like grasses, woods, papers and other rubbers, stalks, etc. The Bio-ethanol is one type of biofuels which can be added to petrol and it increases the fuel cost-benefit ratio.
In India, the government allows adding 5 percent bio-ethanol to petrol, and there was a proposal to further increase the percentage. While in Brazil, an addition of 25 percent of bioethanol to petrol is allowed.
Bioethanol is made from large amounts of cane in Brazil. It is challenging to get bioethanol from the food crops (waste, stalks), but not impossible. Last year, a group of biotechnology industry organizations located in Washington, DC (USA) estimated that second generation biofuels alone can reduce the annual imports of mineral resources up to USD 70 billion in America by 2022.
The production of the first-generation biofuel will decrease as people start using the second generation biofuel sources.
Biodiesel is made from oilseed while Ethanol is made from sugarcane and grains. Biomass energy source is generated from the heat transfer of biomass. Ethanol is also made from cellulose which is available in grass, paper, wood, etc.
The production of second generation biofuels will increase across the globe by 2050 and could achieve around 250 billion joule of energy from it. The first generation biofuel production will be in excess of 50 billion joule in 2025 and as per some estimates, it will decrease by 40 billion joule energy in 2050.
Thus, there will be a major gap between sources of first and second generation of biofuel; the first and second generation of biofuel sources will generate around 40 billion joule and 250 billion joule of energy by 2050. It will be less than four percent of the world’s primary energy demand.
However, Bruce Dale, the head of the bio-based technology head of Bial Michigan State University, East Lansing in America, is still more optimistic. According to him, biomass theory of the second generation can produce 350 billion liters of biofuels annually. This product was just as a full import of American oil.
To do this, there should be research to find out the ways that the inorganic walls of greenish cells should be analyzed and after digestion, it can be easily converted into digestive sugars using an enzyme. The fermentation in these sugars may result in bioethanol.
The above scientists and their associates have developed a technique called Ammonia Fibre Expansion (AFEX). According to him, this technique translates into 90% of cellulose bio-ethanol. In this technique, biomass is added to the ammonia-filled tank at 100 degree Celsius. It has 20 times more pressure than atmospheric pressure. After five minutes, the pressure is completely released with the explosion. The heated ammonia and rapid decrease in pressure result in breaking the cell walls. Its cellulose particle dissociates and separates.
Remember that vegetation is made of cells like living organisms. These cells are like a biochemical factory. The cells divide and the vegetation or organism develops. The cell consists mainly of three parts. There is a cell center called nucleus, another cell liquid, and the third is cell wall.
Due to the disintegration of the cell wall, the microscopic gap of its cellulose is reduced, which makes enzyme (enzymatic or prolonged) easier to reach cellulose molecules. This means that the more part of cellulose is converted into sugars. This is a fermentation of yeast with bacteria. As it turns out to be bioethanol or another biofuel. Approximately 300 liters of biofuels can be obtained from a ton of plant materials.
Currently, a wide range of methodologies and tools are available to assess environmental, social and economic indicators of first and second generation biofuels.
Bioenergy projects should be based on a regional assessment of feedstock potentials (including regional sustainability aspects) and sustainability of feedstock production.
The land resources for the production of energy crops are limited and in some cases, subjects to competing uses and further effort are needed to foster the production of 2nd generation biofuels from wastes and residues.
The process energy supply is often the biggest driver for environmental impacts during biomass conversion. The Life Cycle Assessment (LCA) approaches can help to identify and assess options for optimisation.