Bioelectricity and biofuel production through Sugarcane begaes
Sugarcane is native to Asia and grown here for over 4000 years. Around 400 B.C, in India different methods were developed to extract sugar from sugarcane. Sugarcane is known as one of “cash crops” of early colonial America. Sugarcane produces large amount of bagasse per acre, leaves and cane stalk that can be used for ethanol production (ethanol can be produced through processing of whole cane to generate electricity). On commercial scale Shakarganj Mills Ltd originated New Biogas Power Plant in Jhang. As there is a need to overcome shortage of energy in Pakistan that is 3500-MW, so this new plant is able to provide enough energy to serve more than 50,000 homes in Pakistan. Moreover, is can also generate energy to support different operations of industries and help mills to fulfill their requirements. In its Jenbacher gas engine, biogas is used as fuel that is extracted from spent wash (ethanol production operation residues from sugarcane molasses). Jenbacher gas engine is known for its durability, its ability to work in different fuels and reliability that make it preferable to overcome energy challenges. Moreover, free and available energy from mill biomass (mill’s waste) used in it make it cost effective. The plant is considered eligible for carbon credits due to its renewable energy source. Its advantages like energy efficiency in mills and displacement of energy generated through fossil fuels. As a result of this displacement, it is expected that plant can produce nearly 20,000 tons CERs (certified emission reduction) annually which ensures financial decision making process to work efficiently for customers. This was the first successful sugarcane Biogas power plant project in Pakistan that was registered with United Nations Framework Convention on Climate Change (UNFCCC) by Carbon Services Pakistan and 1st climate AG.
Due to high oil prices and energy challenges it is necessary to shift global energy to renewable energy sources. In Florida (US state), factory powered by bagasse is named as Clewiston Sugar Factory. In Brazil, electricity is produced from sugar and ethanol plant by heating cane straws and bagasse in boiler that produce steam for power generation. The plants can produce 18,000 MW surplus electricity (3% of the country overall need). According to Brazilian Sugarcane Industry Association, an average of 15,000 MW could be produced by 2020 from sugarcane industry to provide up to 15% of total electricity in Brazil.
Sugarcane is known the most valuable crop due to 1G ethanol production having energy balance of 9.3 produced/consumed toes (ton of oil equivalent). Advanced technology and facilities has made ethanol production efficient process to overcome the energy demands and export the surplus electricity. Presently, 86% cars in Brazil are flex fuel that have run through ethanol and bagasse mixture. 2G ethanol production for industrial utilization required biochemical route in which enzymatic hydrolysis of biomass takes place followed by fermentation. Sugarcane bagasse is immediately available at plant site that is important source of ethanol production and certainly it will be an important biofuel. Sugarcane trash mostly contains leaves that can increase the ethanol production when passed through the boiler as they increase bagasse for hydrolysis.
Keeping in mind the economic and environmental analysis, although this electric energy is economically feasible but its environmental affect was greater than one for 2G ethanol production. First and second generation ethanol production processes are shown in Figure 1 and 2 respectively
It is concluded that energy production from sugarcane bagasse is needed to fulfill current and future energy demands as bioelectricity and biofuel. It is interesting idea to enhance the fuel ethanol production that can be possible by greater availability of sugarcane bagasse. For compensate the energy challenges it is efficient and economically good way to take it as an alternative source of fuel and electricity. To get benefit from this, there is need to addressed and focused on government policies to achieve cost effective and environment friendly results for a longer time.
Department of Plant Breeding and Genetics