D.K. Subramanian

Present and prospective role of bioenergy in regional energy system

Bioenergy is the energy released from the reaction of organic carbon material with oxygen. The organic material derived from plants and animals is also referred to as biomass. Biomass is a flexible feedstock capable of conversion into solid, liquid and gaseous fuels by chemical and biological processes. These intermediate biofuels (such as methane gas, ethanol, charcoal) can be substituted for fossil based fuels. Wood and charcoal are important as household fuels and for small scale industries such as brick making, cashew processing etc. The scarcity of biofuels has far reaching implications on the environment. Hence, expansion of bioenergy systems could be influential in bettering both the socio-economic condition and the environment of the region. This paper examines the present role of biomass in the regions (Uttara Kannada District, Karnataka State, India) energy supply and calculates the potential for future biomass provision and scope for conversion to both modern and traditional fuels. Based on the detailed investigation of biomass resource availability and demand, we can categorise the Uttara Kannada District into two zones (a) Biomass surplus zone consisting of Taluks mainly from hilly area (b) Biomass deficit zone, consisting of thickly populated coastal Taluks such as Bhatkal, Kumta, Ankola, Honnavar and Karwar. Fuel wood is mainly used for cooking and horticulture residues from coconut, arecanut trees are used for water heating purposes. Most of the households in this region still use traditional stoves where efficiency is less than 10%. The present inefficient fuel consumption could be brought down by the usage of fuel efficient stoves (a saving of the order of 27%). Availability of animal residues for biogas generation in Sirsi, Siddapur, Yellapur Taluks gives a viable alternative for cooking, lighting fuel and a useful fertiliser. However to support the present livestock population, fodder from agricultural residues is insufficient in these Taluks. There is a need to supplement the fodder availability with fodder crops as successfully tried in Banavasi village by some progressive farmers.

Domestic energy consumption patterns in Uttara Kannada District, Karnataka State, India.

Abstract Energy planning of any region should be based on existing levels of energy consumption. Sectorwise disaggregated information of energy usage is developed for the Uttara Kannada District to assist in the regional energy planning exercise. This paper provides comparative analyses of village level domestic energy consumption patterns across coastal, interior, hilly and plain zones considering regional and seasonal variations. Cooking, water heating and space heating are the major end use activities. The results, based on eighteen months of field research in five taluks of Uttara Kannada, reveal that the average energy consumption norm does vary significantly for cooking and water heating in various seasons across the zones. Among the five taluks, 90 villages (out of 119) and all divisions of Kumta town in the Kumta taluk and 190–220 randomly selected households in selected villages of Sirsi, Mundgod, Siddapur and Ankola were studied. A survey of 1304 households from 90 villages in the Kumta taluk shows that most of them still use traditional stoves for cooking (97.92%) and water heating (98.3%). Average consumption (kg/person/day) for cooking ranges from 2.01±1.49 (coastal) to 2.32±2.09 (hilly). Seasonwise cooking fuel wood requirement for coast and hilly zones, ranges from 1.98 and 2.22 (summer) to 2.11 and 2.51 (monsoon), respectively, while for water heating (for bath and washing), it ranges from 1.17±0.02 (coast) to 1.63±0.05 (hilly). Seasonal variation is evident from the range 1.12 and 1.53 (summer) to 1.22 and 1.73 (monsoon) for coastal and hilly zones, respectively. Analysis of other sources of energy for domestic purposes shows that kerosene is used for cooking and lighting in the coast. Kerosene consumption (l/person/month) for cooking ranges from 0.05 (hilly) to 0.34 (coast) and for lighting ranges from 0.75 (coast) to 0.99 (hilly). Availability of bioresources in hilly zone is the main reason for less consumption of kerosene for cooking. In the hilly zone, electrification of all households has not been possible, as they are scattered. Because of the erratic supply during all seasons (especially monsoon), electrified households also depend on kerosene for lighting. Based on fuel consumption norms (regionwise, seasonwise and end usewise), (a) the total fuel wood required (cooking, water heating, space heating, jaggery making and parboiling) works out to 1.668,698.23 tonnes/year, (b) the electricity demand, excluding irrigation, is about 32.65 million kWh/year and (c) the kerosene demand for cooking and water heating is about 15.86 million litres per year.

Wind energy potential assessment in Uttara Kannada district of Karnataka, India

Availability of wind energy and its characteristics at Kumta and Sirsi in Uttara Kannada District of Karnataka has been studied based on primary data collected at these sites for a period of 24 months. Wind regimes at Karwar (1952–1989), Honnavar (1939–1989) and Shirali (1974–1989) have also been analysed based on data collected from India Meteorological Department (IMD) of respective meterological observatories. Wind energy conversion systems would be most effective in these taluks during the period May to August. The monthly frequency distributions of wind speed have been analysed for Kumta and Sirsi where hourly wind speed recording is available. It is shown that two parameter Weibull distribution is a good representation of the probability density function for the wind speed. Energy Pattern Factor (EPF) and Power Densities are computed for sites at Kumta and Sirsi. With the knowledge of EPF and mean wind speed, mean power density is computed for Karwar, Honnavar and Shirali. Our analyses show that the coastal taluks such as Karwar and Kumta have good wind potential. This potential, if exploited would help local industries and coconut and areca plantations. Premonsoon availability of wind energy would help in irrigating these orchards and makes the wind energy a desirable alternative.

End use efficiencies in the domestic sector of Uttara Kannada District

End use efficiency experiments conducted in some households of Masur village (based on 4 days experiment) of Kumta taluk show that there is scope for saving 27-42% of energy by switching to improved devices, which are designed to maximise combustion rate (of fuel, ensuring the presence of sufficient oxygen), radiant heat transfer (from fire to vessels, keeping them as close to fire as possible), convection (to pass maximum hot gas over vessels, reducing drafts), conduction (heat is concentrated near the vessels by using insulating material for the stove) and user satisfaction (with user friendly design). The thermal performances of improved stoves designed at our Institute (ASTRA) have also been studied in the field. Irrespective of type of fuel, community, etc., improved stoves show significant saving in fuel. By switching to energy efficient devices 450,548 to 700,853 tonnes of fuel wood can be saved per year in the district.

Hydroelectric resource assessment in Uttara Kannada District, Karnataka State, India

The amount of power available at a given site is decided by the volumetric flow of water and the hydraulic head or water pressure. In hydro schemes, the turbines that drive the electricity generators are directly powered either from a reservoir or the ‘run of the river’. The large schemes may include a water storage reservoir providing daily or seasonal storage to match the production with demand for electricity. These schemes have been producing power in Karnataka for many years, with the first hydroelectric station built in 1942. The majority of them are in Uttara Kannada district. Due to environmental constraints, further construction of storage reservoirs is limited and attention has been focussed towards developing environmental friendly small-scale hydro schemes to cater for the needs of the region. In this paper, the assessment of potential carried out in the streams of Bedthi and Aghnashini river basins in Uttara Kannada district of Western Ghats is discussed. Potentials at five feasible sites are assessed based on stream gauging carried out for a period of 18 months. Computations of discharge on empirical/rational method based on 90 years of precipitation data and the subsequent power and energy values computed are in conformity with the power calculations based on stream gauging. It is estimated that, if all streams are harnessed for energy, electricity generated would be in the order of 720 and 510 million units in Bedthi and Aghnashini basins, respectively. This exercise provides insight to meeting the regional energy requirement through integrated approaches, like harnessing hydro power in a decentralized way during the monsoon season, and meeting lean season requirements through small storage, solar or other thermal options. Net energy analyses incorporating biomass energy lost in submergence show that maximization in net energy at a site is possible, if the hydroelectric generation capacity is adjusted according to the seasonal variations in the river’s water discharge.

Analysis of energy utilization in the grain mill sector in Karnataka

Energy is a major constituent of a small-scale industry such as grain mills. Based on a sample survey of several mills spread over Karnataka, a state in India, a number of energy analyses were conducted primarily to establish relationships and secondarily to look at them in more detail. Initially specific energy consumption (SEC) was computed for all industries so as to compare their efficiencies of energy use. A wide disparity exists in SEC among various grain mills. In order to understand the disparities better, regression analyses were performed on the variables energy and production, SEC and production, and energy/SEC with percentage production capacity utilization. The studies show that smaller range industries have lower capacity utilization. This paper also examines the energy savings possible by shifting industries from the lower production ranges to the next higher range (thereby utilizing installed production capacity optimally). This leads to an overall energy capacity saving of 23.12% for the foodgrain sector and 18.67% for the paddy dehusking subgroup. If this is extrapolated to the whole state, we obtain a saving of 55 million kWh.

Optimal design of hydroelectric projects in Uttara Kannada, India

Abstract The planning of water resources depends on the type and size of projects, the ecological factors involved, etc. Emphasis is placed on presenting an overview of water resources through meteorological, hydrological, ecological and economic data. Economic data include all costs and benefits, specifically those hitherto under estimated, environmental social costs and benefits. This study was carried out on the Bedthi and Aghnashini rivers in the Uttara Kannada district of the Western Ghats region, Karnataka State, India. It is estimated that 720 and 510 million kWh of electricity can be generated in Bedthi and Aghnashini River basins, respectively, if all the streams are harnessed. Focusing on land submergence impact, a model is proposed to minimize submergence and maximize net energy in a region with seasonal power generation, reservoir storage capacity (to meet the regions demand during all seasons) and installed generation capacity as the decision variables. Net energy analyses incorporating biomass energy lost in submergence show that maximization in net energy at a site is possible if the hydroelectric generation capacity is adjusted according to the seasonal variations in the rivers water discharge. A Decision Support System (DSS) used for optimal design of hydroelectric projects in Uttara Kannada district is discussed.

Industrial energy utilisation in Karnataka and potential savings

Energy is essential for industrial production. Because of the past abundance of low-cost energy, historically, the rate of social progress among industrial societies has not been limited by energy availability. Energy cost has not been significant when compared with no energy use. Mechanisation of agriculture, increased use of electrical appliances in the domestic sector and rapid industrialisation to meet the demand of exponentially growing population have resulted in an energy crisis. The raised fossil fuel prices and the environmental factors playing the dominant role in implementation of large scale projects, such as hydro, thermal and nuclear, have aggravated the problem further. In this context, an integrated energy plan for a country seems essential for ecologically sound development of a region. An integrated plan includes strategies to: • improve the efficiencies of end use devices and/or conversion equipment in all sectors; • optimise energy sources (end use matching); • maximise the use of renewable resources; • balance the exploitation of biomass energy resources; and • discourage the use of depletable resources. Conservation through improvement of the efficiencies of end use devices is one of the most effective ways to provide immediate relief for the energy problem. This helps to maintain economic growth and social progress of a region. Environmental problems, resource depletion and growing demand of energy in the state/region make it increasingly imperative that we use energy as efficiently as possible, and planners should take note of this untapped resource. The potential for improved energy efficiency is great, and a substantial part of that potential could be realised in the course of events. The industrial sector constitutes a major consumer of commercial energy. Improvement of energy efficiency in the industrial sector would result in a slower rate of energy growth. A secure energy supply is the major concern of most industrialists. It is, thus, necessary to examine industrial energy use and the economy. The analyses of consumption patterns and the assessment of feasible energy conservation possibilities show that the potential for energy conservation in the industrial sector and in all sectors is substantial. The barriers identified to tap this potential are a lack of information on specific measures and options for achieving energy conservation, lack of capital for schemes involving technology upgrading and efficiency improvements, pricing policies which deviate from rational tariffs and the inadequacy of institutional arrangements for promoting energy conservation in different sectors of the economy. In this regard, research should be sponsored to develop system designs, cost and pricing policies, problems related to system interconnection with public utilities and an assessment of potential energy savings, and research into methods of matching energy resources to work requirements, rather than vice versa, for improved efficiency. It is essential for the planning machinery to foster the integrated approach in energy planning of a region. This paper discusses an attempt made by us to illustrate the industrial energy scene in Karnataka and reveals the possibilities of energy conservation. Analysis of the energy consumption data of Karnataka and India shows that the per capita consumption of energy is low (compared with 56 countries in the world), while for the industrial sector, energy per state domestic product (SDP comparable to GDP) is at least 10–20 times higher than that of industrialised countries. This implies inefficiency in energy utilisation. Detailed investigation of the industrial sector through analysis of the Specific Energy Consumption (SEC)—industry wise and yearly for a seven-year period—reveals that about 27.72% of energy could be saved in the industrial sector. This, when quantified, accounts for savings of 1541 million kWh per year in Karnataka, which is equivalent to the power output of 300 MW (Mega Watts) electric power generating station (hydro/thermal).

Energy efficiencies of end-use devices in an electro-metallurgical industry: A critical study

The inefficient use of energy in a large number of industries is slowly developing into a major energy crisis in the already power-starved Karnataka State, India. This study attempts to bring out the present inefficient pattern of energy use in an electro-metallurgical industry. It also brings out the considerable scope for energy conservation, especially by increasing the efficiency of the end-use devices used. This concept, when extended to other industries, wherein increasing efficiency of the end-use devices would provide the desired end results with small energy input. This, in turn, would result in a slower rate of energy growth as well as saving in energy use.

ENERGY REQUIREMENTS AND CONSERVATION POTENTIAL IN INDUSTRIAL SECTOR IN KARNATAKA

SYNOPSIS Energy is essential for industrial production yet this sector constitutes a major consumer of commercially produced energy. An improvement in energy efficiency in this sector would result in a slower rate of energy growth. Secure energy supply is the major concern of most industrialists, hence it is necessary to examine industrial energy use and its impact on the economy. Analyses of consumption patterns show that the potential for energy conservation in the industrial sector, as in all other sectors, is substantial. The barriers preventing achieving this potential include: • A lack of information on specific measures and options for achieving energy conservation; • The inadequacy of institutional arrangements for promoting energy conservation in different sectors of the economy. Conservation through end use efficiency and good house keeping practices are the most effective ways to provide immediate relief for energy scarcity. This will help to maintain economic growth and social progress of a region. Environmental problems, resource depletion and growing demand of energy in the state/region make it increasingly imperative that energy is used as efficiently as possible. This paper discusses an attempt to illustrate the industrial energy scene in Karnataka, India and the possibilities for energy conservation. Analysis of energy consumption data of Karnataka and India shows that the per capita consumption of energy is low (compared with 32 countries in the world). However, for the industrial sector, energy per state domestic product is at least 10–20 times higher compared to that of industrialised countries. This implies inefficiency in energy utilisation. Detailed investigation of the Industrial sector, through analysis of Specific Energy Consumption (SEC)—industry wise and year wise for a seven year period reveals that about 28% energy could be saved in the industrial sector. This, when quantified, accounts for a saving of 2.25 mtoe of energy or 1541 million kWh electrical energy per year in Karnataka. Such a saving is equivalent to the energy output of 300 MW (Mega Watts) electric power generating units (hydro/thermal).