India is the fourth largest consumer of petroleum energy and the fifth largest overall energy consumer in the world. In order to meet the country’s high demand for energy, India’s government is in search of sustainable energy sources that both meet these needs and do not contribute significantly to global warming. While 93% of urban areas in India have electricity, 47% of populations in rural areas lack it (IEA 2009). Therefore, it is necessary for India’s government to find ways to not only meet the growing demand of the nation, but also find sources of energy that can provide and sustain energy in the rural areas. India’s dependence on fossil fuels is so strong that any price increases or decreases in oil imports would have a significantly negative impact on India’s economy. Hemaiswarya et al. (2012) suggest that in order for India to minimize negative impacts on the environment and maintain stability in regards to their energy sources they must efficiently utilize already-existent fuel resources. They also suggest that India must consider alternative and more diversified energy sources, such as microalgae. In order to investigate alternative energy sources Hemaiswarya et al. examine the positive and negative externalities of six renewable energy sources. —Shelby Long
Hemaiswarya et al., 2012. An Indian scenario on renewable and sustainable energy
sources with emphasis on algae. Applied Microbiology and Biotechnology 96, 1125–1135.
Hemaiswarya et al. analyzed biomass, biogas, biohydrogen, bioethanol, biodiesel, and microalgae in order to determine which would be the most efficient and least environmentally harmful energy sources for India. Biomass refers to both dry fuel sources, such as wood, and wet sources, such as agricultural or industrial waste, wastewater, and slurries. The smoke that results when coal and biomass are burned within households can cause respiratory infections, lung cancer, and other fatal illnesses (World Health Organization 2009). Therefore, Hemaiswarya et al. suggest that biomass materials, such as bagasse, rice husk, coffee waste, and sawdust, should be used in gasification systems which will not create this harmful smoke and will harness the biomass for energy and thermal purposes. The second energy source they investigated was biogas, which is a renewable fuel produced by the anaerobic digestion of the organic animal, agricultural, and industrial waste. The high amount of methane present in biogas makes it an especially effective source of energy. Biohydrogen was also analyzed by Hemaiswarya et al. as a viable energy source for India’s growing need for renewable and economically-stable energy sources. The use of biohydrogen as a renewable energy source is not highly developed in India; however, biohydrogen energy is extremely useful for a variety of energy needs and does not contribute to greenhouse gases. An obstacle in harnessing biohydrogen energy is that the necessary hydrogen must be split from H2O with the help of enzymes that can only work under specific conditions. Hemaiswarya et al. recognize that India has made advances towards being able to harness H2 fuels, yet challenges such as availability of feedstock types and identification of ideal conditions for the hydrogen production have not been perfected. Both bioethanol, created when sugar-containing materials ferment, and biodiesel, produced from fatty acid of ethyl and methyl ester from virgin and used vegetable oils, were also viable energy sources examined by the researchers. The main crop in India used for the production of ethanol is sugarcane, and with the current 330 distilleries in India they estimated that about 1.5 million liters of fuel ethanol could be produced. However, ethanol is not a main priority in the current economy; therefore, this estimate is not being met. On the other hand, biodiesel produced from plants, such as Jatropha, has the potential to be a major contributor to India’s renewable energy needs. Hemaiswarya et al. propose that India use degraded lands and forests, railway tracks, irrigation canals, and other public places to grow the plants (Kumar and Ram Mohan 2005). However, obstacles that inhibit the increased production of biodiesel are lack of feedstock and increases in wage rates. Lastly, Hemaiswarya et al. examined the use of microalgae in the production of biofuels. They determined that microalgae can potentially be harnessed to produce high amounts of biodiesel due to its high growth rate, adaptability, and photosynthetic efficiency.
All six of the renewable energy sources Hemaiswarya et al. considered are possible sources of energy for India in the coming years; however, some are more developed and viable for use on a mass scale in the near future than others. Biomass, biogas, and biohydrogen are already being used as energy sources in India on a smaller scale, yet there is potential to expand production after further research and development of the industries. Hemaiswarya et al. indicated that in order for bioethanol fuel to become a leading renewable energy source in India, current potentials for sugarcane ethanol must be met by increasing the production of the necessary raw materials. Likewise, similar steps must be taken in order to increase and fulfill the potential levels of production of biodiesel. They suggest that wastelands and other undesirable land in India should be used for the production of biodiesel feedstock. Researchers estimate that one hectare of Jatropha plantation (about 4,400 plants) can supply about 1,500 liters of oil; therefore, about three million hectares of Jatropha could account for about 10% of current fossil diesel demand (TERI (The Energy and Resources Institute) 2004).
Hemaiswarya et al. also determined microalgae to be a highly feasible option in helping India meet its energy needs because of its high growth rates, adaptability to different aquatic environmental conditions, and high oil yield. In addition, Hemaiswarya et al. suggest that biodiesel would be a suitable energy source for India because of current easily-attainable technologies, such as the process of transesterification and photobioreactors, that can be used in the growing of and conversion of microalgae into biodiesel. However, there are still developments and research that must be achieved in order produce microalgae biodiesel on a mass scale, including the selection of microalgae that are high in lipid content, water chemistries, determining nutrient requirements, and perfecting methods for conversion of microalgae into biofuel. Hemaiswarya et al. maintain that in order for India to insulate itself from the often-unstable global fossil fuel economy it must harness alternative energy sources and especially look into the benefits of microalgae biodiesels. Many of these possible sources do not contribute to global warming like fossil fuels do and can be produced by harnessing various aspects of India’s unique natural environment. Hemaiswarya et al. argue that India should commit more resources to the development of alternative energy sources because not enough research is being devoted to finding solutions for the imminent energy crisis.
IEA (2009) World energy outlook. International Energy Agency, Paris
Kumar L, Ram Mohan MP (2005) Biofuels: the key to India’s sustainable energy
needs. Proceedings of the RISO International Energy Conference, RISO, Denmark, RISO-R-1517(EN), pp 423–438
TERI (The Energy and Resources Institute) (2004) Livelihood improvement through
biomass energy in rural areas. TERI, New Delhi
World Health Organization (2009) Global health risks: mortality and burden of
diseases attributable to selected major risks. World Health Organization, Geneva.<http://www.who.int/healthinfo/global_burden_disease/global_health_risks/en/index.html>