Renewable energy is now a burning issue for sustainable development. Moreover, it is also environmentally compatible. Energy demand and environmental concerns have significantly constrained the sustainable development of Bangladesh economy, which has been experiencing record levels of energy consumption. At present, traditional fossil fuels are used predominantly in Bangladesh. Present commercial energy consumption is mostly natural gas [around 66 percent], followed by oil, hydropower and coal. A recent survey reveals that power outages result in a loss of industrial output worth US$1 billion a year which reduces the GDP growth by about half a percentage point in Bangladesh. Form the last 3 years government also stops giving the new gas and electricity supply at home or industry for the shortage of production. Renewable and environmentally friendly energy sources have therefore become a crucial factor defining the economic and social sustainability of the country. In my previous issue, I have mentioned solar energy is the most abundant clean energy for Bangladesh at present. Government and some nongovernment organization already take some steps for this emerging sector. Today’s article I would like to write about second and third generation biofuel that desire great attention for present and future sustainability.
Biodiesel and bioethanol are still in its infancy in Bangladesh, although its future is promising. The term biofuel generally refers to either biodiesel or ethanol and denotes any fuel made from biological sources, for most practical uses. The terms first, second and third generation can be used in the contexts of both feedstocks and process. For instance, corn and maize represent first-generation ethanol feedstocks, and fermentation represents the first generation ethanol production process. Second generation biodiesel is obtained from non-food bio-feedstocks, energy crop such as Jatropha represents the second generation biodiesel feedstock. These feedstocks have the advantage of non affecting the human food chain and can be grown in marginal and wastelands. Lignocellulosic biomass, particularly agricultural residues also one of the best choice for biofuel production. Algae are considered to belong the third generation of biofuel feedstock. These feedstocks offer superior yields when compared to second generation feedstock and do not have an effect on the human food chain. In addition, crops such as algae can grow in places that are not suitable for agriculture, thus providing superior ecological performance as well.
Biodiesel and bioethanol have attracted great attention in the USA, European countries, China, Japan, and India for significant advantages over fossil diesel. Two priorities in the agenda of Bangladesh government may take steps for biodiesel projects, science the country has experienced a drastic increase in oil imports within the past decade, and in the meantime has the vast agricultural population. On the other hand, biodiesel consumption generates less environmental pollutants such as Sox and NOx and mitigates CO2 emission. At presents, our government and nongovernment organizations may collect a huge fund from the international body for renewable energy research from carbon fund that may facilitate this sector rapidly.
In the USA and European countries, biodiesel production mainly uses rapeseed, soybean, and others oil crops as feedstocks, while in Bangladesh will not rely on these crops, which are sources for edible oils. In the long term, oil plants such as castor, Jatropha will be sustainable feedstocks for Bangladesh’s biodiesel or bioethanol production. Biofuel production from algae exhibits good potential, this is not economically competitive yet in others countries.
Accurate data is unavailable about oil-bearing plants families and their production and utilization in Bangladesh. Jatropha, Mahua and Pongamia plant are the main candidate for biodiesel production in Bangladesh. During 2009, while working on a project in Plant Biotechnology Division, Bangladesh Atomic energy Commission, Savar, we planted Jatropha, and cassava plant for the future biodiesel project. As my knowledge, there is no progress for this project due to lack of proper policy and sufficient fund. In Bangladesh Khwaja Agri-Horticultural Research Centre (KAHRC) is the first organization to produce bio-diesel from Jatropha seeds at the Bangladesh Ansar and VDP Academy, Gazipur. Bangladesh environmental condition is favourable for Jatropha plantation as its can grows from dry subtropical regions to tropical rainforest. Others energy crops and cellulosic crops may also be used for biodiesel production. Use of food crops may arise the problem in the food supply. Microalgae are one of the promising feedstock for biofuel production. Bangladesh has huge natural water resources for easy algae cultivation. In addition, they can utilize marginal land and brackish and wastewater thus do not compete with agriculture for land and water resources. Thus, large-scale cultivation of oleaginous algae holds the potential to simultaneous alleviate energy crisis, CO2 emission and environmental concerns.
The transesterification reaction is the core of biodiesel production. The transesterification reaction can occur with the use of acid, alkali, or enzyme as catalysts, or in a supercritical fluid system without a catalyst. Currently, many technologies are under development for biodiesel production. Through an overview on biodiesel development in developed countries such as America, Germany, and Japan, and less developed countries such as South Africa, Brazil, Korea, India, Thailand, and China are a good example of the development of this alternative fuel industry from the aspects of policies, technologies, facilities and vehicle manufacturing, etc. The first industrial facility in the world for lipase-mediated biodiesel production was built on December 8, 2006, with the biodiesel production capacity 20,000 ton/year, which was extended to 40,000 ton/year in 2008.
Bangladesh can set up small or medium size biodiesel industry for increasing demand for energy and be suffering from a shortage of crude oil supply and strongly depend on imported oil for their economic and social development. It is believed that with the modification of relevant laws and regulations, and close co-operation among scientific research personnel, institutes, and enterprise, advanced technologies are expected to be put into large-scale application in the near future. More preferable policies and/or strategies are needed to balance the fraction of renewable energy in the Bangladesh market to foster the industrialization in the near future. Meanwhile, more investment is needed for fundamental studies and technology innovations targeting low-cost and high energy recovery from existing local biomass.