Biomass gasification for decentralized power generation: The Indian perspective
Introduction
For a developing country like India, energy is the fundamental input for economic growth. The current target of economy growth rate is 10% and the energy demand in various sectors such as agriculture, industry, transport, commercial and domestic is fast rising. Electricity is perhaps the most vital form of energy input required for infrastructural development of the country in agriculture and industry, and it also plays a critical role in socio-economic development. The total installed capacity of power generation through various sources (as on February 2009) is about 147.72 GW with gross generation of more than 700 billion kWh [1]. The distribution of power generation through different sources, however, is uneven as shown in Fig. 1. The thermal power contribution to this is ∼63% followed by hydropower contributing ∼25%. The share of nuclear power is the smallest with ∼3%, and the power generation through renewable sources contributes the remaining ∼9% [2], [3]. The exact distribution of the power scenario in various states of India is given in Table 1. After grouping of the states into various regions, the distribution of power generation is shown in Fig. 2. The reason behind this uneven distribution is that India has over 200 billions tons of coal deposits. Thus, the generation is mainly dominated by coal-based thermal power plants. However, the coal reserves are mainly concentrated in the north and northeastern states of India and not uniformly spread in the country (refer to Table 2 for distribution of coal deposits in various states). Presently the generation capacity is far insufficient to meet the demands. Although per capita electricity consumption in India during the past 5 years has risen from 566.7 to 704.2 kWh (refer to Fig. 3), it is still far below the global average of 2000 kWh [4]. Currently, the estimated average gap between supply and demand of electricity (peak demand) is about 14%. The transmission and distribution losses are estimated between 26 and 32%. With rapid urbanization and industrialization, this gap is bound to rise fast. In addition, rural electrification has also posed a major challenge to India's growth. The major hurdles in rural electrification are extension of the grid to remote areas, large transmission losses and low peak loads due to small and isolated population [5], [6], [7]. Unlike urban areas, the primary electricity need of the rural population is for domestic lighting, running of irrigation pumps and small-scale commercial activities such as floor mill and other rural industries. The National Electricity Policy (NEP) announced by Government of India along with other activities such as Rajiv Gandhi Grameen Vidyutikaran Yojana has given high priority to rural electrification. The primary aim of this is to achieve complete rural electrification by 2010. Table 3 gives a more detailed account of the status of rural electrification in various states of India. In order to present a realistic picture of rural electrification, Ministry of Power of Government of India has modified the definition of an “electrified village”. Earlier definition of electrified village was “a village in which electricity is being used within its revenue area for any purpose whatsoever”. In 2004–2005, this definition was given four important criteria as follows [8], [9]:
- 1.
Provision of basic infrastructure such as distribution transformer and distribution lines in the inhabited locality.
- 2.
Provision of electricity to public places like schools, Panchayat offices, health centers, etc.
- 3.
Access of electricity to a minimum of 10% households in the village.
- 4.
Compulsory certification from Gram Panchayat regarding completion of village electrification.
Although the overall rural electrification stands at an impressive figure of 82%, the actual number of households accessing the electricity is mere 44% [10]. Presently, the rural electrification is growing at a rate of 3–6% annually [9], [11]. In very remote areas where extensive of grid is not feasible, decentralized power generation through renewable sources offers a viable solution for meeting the electricity needs of the local population [12], [13], [14]. In fact, the NEP insists on use of both conventional and renewable sources of electricity generation, as long as they are economically viable. In order to reduce load on grid and state electricity boards, NEP emphasizes use of renewable energy even in areas with access to grid, provided renewable sources are as economic as conventional ones. Options for decentralized generation through renewable sources for are wind energy systems, solar photovoltaics, biomass gasifiers and small hydropower systems, etc. [10]. The most economic option depends on the location of area and natural resources available [15]. Another motive for exploration of renewable sources for power generation is the fluctuating economy of the conventional sources. The principal sources of energy are fossil fuels such as coal, oil and gas. However, the prices of oil and gas are highly fluctuating and there is also a fear of their acute shortage in the future. Moreover, emancipated use of fossil fuels also causes environmental pollution problems such as emission of greenhouse gases. Thus, there is an urgent need for harnessing the large potential of renewable energy sources in a planned and strategic manner to reduce the gap between demand and supply. Promotion of energy conservation and increased use of renewable energy are the twin planks of a sustainable energy supply [14], [16]. In this paper, we have attempted to review the feasibility of the decentralized power generation through biomass gasification and technical and economic aspects related to this. The estimated annual biomass production in India is 200 million tons, which (unlike coal) is distributed almost evenly in the country (greater details about this are given in section 3). This is equivalent of 20 GW of installed capacity. In addition, agro-residues and woody bio-residues from wastelands (estimated at 60 million hectares) could add another 100–300 million tons, which amount to 45 GW of installed capacity. However, the total installed capacity of biomass-based power generation (inclusive of bagasse and non-bagasse cogeneration and biomass gasifiers; as of September 2007) is 838 MW [17]. This capacity is mainly through cogeneration (692.3 MW through bagasse fired boilers), which is an inefficient method of utilization of the biomass energy. This indicates that the vast potential of biomass power remains almost unused, and there is an urgent need of utilization of this resource through more efficient technologies such as biomass gasification.
Section snippets
Brief history of renewable energy efforts in India
The main renewable sources are solar energy, wind energy, small hydropower, biomass, biogas and energy recovery from municipal and industrial wastes. India has tremendous natural resources that have potential of all of the above-mentioned renewable energy sources. The advantages of renewable energy are: (1) complete perpetuity; (2) local availability without needing major transport; (3) modularity, i.e. economy is independent of scale; and (4) non-polluting nature (carbon neutrality).
Biomass power in India
Per the Public Utility Regulatory Policies Act (PURPA, 1978) in USA, the word “Biomass” refers to any organic material not derived from fossil fuels. However, in the context of biomass-based power generation, biomass refers to essentially all organic matter that originates from plants – including all land and water-based vegetation such as algae, trees and crop residues. Biomass has been a primary energy source for cooking and heating. It is estimated that if all biomass used in India was
Technology for biomass gasification
Before we proceed to analysis of technical and economic feasibility of decentralized power generation through biomass gasification in the Indian context, we would like to discuss various technologies available for gasification of biomass and present a comparative analysis of the same. Depending on the mode of biomass–air (or oxygen) contact, biomass gasifiers are classified into two main types, viz. (i) fixed bed, and (ii) fluidized bed. The sub-categories for the fixed bed type gasifiers based
Economics of biomass gasification
The principal components of the capital cost of biomass gasifier system (either updraft or downdraft) are biomass gasifier unit (which is essentially a combustion–gasification chamber made of stainless steel), a gas cooling and cleaning unit (comprising of scrubber and two or three stage filters for removal of particulate matter) and an engine-generator (which could be either of dual fuel type, employing diesel as pilot fuel or it could be operating on 100% producer gas). Other components of
Case studies
About 24,500 villages in various states of India have been identified as remote villages where extension of grid electricity is not feasible. Therefore, all of these villages are proposed to be electrified with renewable energy options such as photovoltaics, micro-hydro, wind and biomass gasification. Among these options, biomass-based electrification stands higher in the Indian context as the biomass is uniformly spread in the country and biomass-based energy has a vital role in the rural life
Overview and conclusions
In this review, we have discussed the technical and economic aspects of decentralized power generation through biomass gasification in the Indian context. Demand for electricity in rural areas is growing at a rate of 7%. Total peak hour shortage of electricity is around 20,000 MW, while annual capacity addition is mere 3000 MW. India's power production potential is determined by coal-based thermal plants. However, coal deposits in India are rather localized in the eastern and northeastern regions
References (81)
- et al.
Decentralized vs grid electricity for rural India: the economic factors
Energy Policy
(1991) - et al.
Electricity access for geographically disadvantaged rural communities—technology and policy insights
Energy Policy
(2004) - et al.
Providing electricity access to remote areas in rural India: an approach towards identifying potential areas for decentralized power supply
Renew Sust Energy Rev
(2008) Comparison of options for distributed generation
Energy Policy
(2006)- et al.
Techno-economics of micro-hydro projects for decentralized power generation in India
Energy Policy
(2006) Commercialising biomass gasifiers: Indian experience
Energy Sust Dev
(2000)Energy production from biomass (Part 1): overview of biomass
Bioresource Technol
(2002)Energy production from biomass (Part 3): gasification technologies
Bioresource Technol
(2002)Biomass gasification in moving beds. A review of European technologies
Renew Energy
(1999)- et al.
Exploration of the possibilities for production of Fischer–Tropsch liquids and power via biomass gasification
Biomass Bioenergy
(2002)
Gasification of biomass wastes and residues for electricity production
Biomass Bioenergy
Air gasification of rice husk in a dual distributor type fluidized bed gasifier
Biomass Bioenergy
Design and operation of a CFB gasification and power generating system for rice husk
Biomass Bioenergy
Gasification of leached orujillo (olive oil waste) in a pilot plant circulating fluidized bed reactor—preliminary results
Biomass Bioenergy
Modeling NH3 and HCN emissions from biomass circulating fluidized bed gasifiers
Fuel
A review of the primary measures for tar elimination in biomass gasification processes
Biomass Bioenergy
Biomass gasifier projects for decentralized power generation in India: a financial evaluation
Energy Policy
Scaling up biomass gasifier use: an application specific approach
Energy Policy
A financial evaluation of biomass gasifier based power generation in India
Bioresource Technol
Biomass energy technologies for rural infrastructure and village power—opportunities and challenges in the context of global climate change concerns
Energy Policy
Techno-economics of small wind electric generator projects for decentralized power supply in India
Energy Policy
Photovoltaic projects for decentralized power supply in India: a financial evaluation
Energy Policy
Electricity generation from rice husk in Indian rice mills: potential and financial viability
Biomass Bioenergy
Sustainability of decentralized wood fuel-based power plant: an experience with India
Energy
Technoeconomic assessment of biomass to energy
Biomass Bioenergy
The technical and economic feasibility of biomass gasification for power generation
Fuel
Economics of biomass energy utilization in combustion and gasification plants: effects of logistic variables
Biomass Bioenergy
Importance of rural bioenergy for developing countries
Energy Conserv Manage
Review of augmentation of energy needs as renewable energy sources in India
Renew Sust Energy Rev
Rural bioenergy centers based on biomass gasifiers for decentralized power generation: case studies of two villages in Southern India
Energy Sust Dev
An assessment of biomass gasification based power plants in Sunderbans
Biomass Bioenergy
Renewable energy development in India
Multiple choice questions on renewable energy
Energy access problem of the poor in India: is rural electrification a remedy?
Energy Policy
Rural energy: goals, strategies and policies
Econ Polit Week
Decentralized renewable energy: scope, relevance and applications in the Indian context
Energy Sust Dev
Energy policy for India: towards sustainable energy security in India in the 21st century
The design of rural energy centers
Indian Acad Sci Bangalore
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