Journal of Scientific & Industrial Research Vol. 62, lanuary-February 2003, pp 1 06- 1 23

Biofuels of India

v V N Kishore and S N Srinivas

Tata Energy Research Institute, Darbari Seth Block, Habitat Place, Lodhi Road, New Delhi 1 1 0 003, India

Biofuels play an important role in meeting energy requirements in the world and its position in the context of the developing countries l ike India is rather vital. The present paper attempts to provide an overview of the resource base, conversion technologies, and emerging end uses and research needs in the overall context in India. Authors also observe that the efForts made in India in modern biomass utilization in the last two decades have not succeeded with the desired level of achievements. Though several alternative techniques/technologies for efficient use of biofuels have been developed, however, they are yet to transform into acceptable package of product with the mechanisms to disseminate them through manufacturer and market network to the end users.

1.0 Introduction

Biomass was the chief source of fuel in the pre­industrial revolution world and is sti l l quite important in any developing countries, such as India. Worldwide, photosynthetic activity is estimated to result in energy amounting to approximately 3000 bi l l ion GJ a-nnually in the form of biomass of which about 1 0 per cent of it i s used for animal feed, fert i l izer, fuel or feedstock (Alexandrov et al. 1 999). The remainder serves the essential purpose of moderating c l imate, recycl ing water and essential nutrients, and performs a host of other ecosystem functions, which are vital to human wel l being.

Although biofuels account for only 1 2 per cent of the global energy requirements in terms of total energy content, they cater to the largest section of energy users . It is estimated that about two-thirds of households in the developing countries are sti l l dependent on biofuels for cooking and heating, and many of these households use open fires or poor qual ity stoves (Capsule Report Jan' 1 999).

The 1 973 , oi 1 crisis and the more recent global c l imate change concerns brought into focus sharply the post-industrial revolution conflict between economic development and energy sustainabi l ity. It has been shown again and again that the best way of resolving this conflict is by promoting energy conservation and renewable energy uti l ization. The importance of biomass as a renewable energy

* Author for communication, . E-mai l : vvnk@teri . res . in

resource, especial ly in i ts prevalent form of stored chemical energy, as opposed to solar and wind energy which fluctuate widely, has increased in the recent years. This can be observed not only in the devel oping countries l ike India, but also III industrial ly developed countries, such as the Netherlands, Germany, Finland and Sweden . The focus on biofuels has increased s ince it is net zero contributor to carbon dioxide. In addition, the global obl igations to reduce carbon dioxide emissions have renewed interest in the biofuels . The present paper attempts to provide an overview of the resource base, conversion technologies, and emerging end uses and research needs in the overal l context of modern biomass uti l ization in India.

2.0 Biomass in India: Resource Base, End Use Efficiency and Emission Characteristics

Most of the developing countries depend heavi ly on biomass for their energy needs and India i s no exception. An estimated 220 mt of firewood i s used for cooking in rural areas and about 1 60 mt of 'non-fodder' agricu ltural residues every year in the country. In general , firewood consumption would show a steady increasing trend (Ravindranath and Hal l , 1 995). Questions of sustainabi l ity of such high consumption levels had been raised in the past, but i t appears that most firewood comes from a variety of local trees and shrubs, chiefly Prosopis Juliflora (locally known as 'Jali '), grown on private land, community l ands, roadsides and wastelands. Though deforestation due to high dependency on firewood for

KISHORE & SRINIV AS: BIOFUELS OF INDIA 1 07

cooking i s of concern in select areas i n the country, there is not much evidence to suggest that firewood use is contributing significantly to forest loss at the national leve l . In fact, sate l l i te data shows that forest cover has increased marginal ly in recent yeas, probably due to i ncreased regulation, better forest management and afforestati on programmes such as Joint Forest Management. Thus the current solid fuel resource stands at about 380 mi l l ion t/y. In comparison, the coal production is about 270 mt and l ignite production is 1 9.5 mt, adding up to about 290 mt of sol id fossi l fue l production per annum. Considering that the calorific values of several biomass residues are comparable to those of high-ash coals, produced predominantly in India, it can be said that the sol id biofue l resource is at least as big as the solid fossi l fuel resource.

Another b io-resource in India i s cattle dung. Nearly 600 mt of wet dung is produced annual ly from a l ivestock population of about 288 m (cattle and buffaloe) (TEDDY 2000/200 1 ) . Table I shows that the l ivestock population is also growing, though the rate of growth is low. This means that the wet dung would be avai lable as a sustainable resource. If al l this dung can be converted into biogas the gas

Table 1- Growth of cattle and buffaloes (mi l l ion)

Year Cattle Buffaloes Total

1 972 1 78.3 57.4 235.7

1 977 1 80. 1 62.0 242. 1

1 982 1 92.4 69.8 262.2

1 987 1 99.7 76.0 275.7

1 992 204.6 84.2 288.8

Source: TEDDY (TERI Energy Data Directory & Yearbook) 2000/200 1

production would be 36 bcM/y. If organic wastes such as sewage, municipal sol id waste, and disti l leries can also be taken as feedstock for gas production the total biogas potential would be 36.8bcM/y. In comparison, 1 9 .3 b i l l i on m3 of natural gas and 3 .42 mt of LPG were consu med in 1 994-95 . In terms of heat energy, this amounts to 0.975 exa joules ( I EJ = J OI 8 J)/y, whereas the biogas production potential is 0.693 EJ/y. Thus the biogas potential , at nearly 70 per cent of the current gaseous fossi l fuel consumption levels , is too large to be ignored . B iomethanation would also produce about 96 mt of manure. In comparison the chemical fert i l izer consumption in 1 997-98 was 1 6.4 mt . The fossi l fuel and bio-resource base of India is summarized in Table 2 .

One major drawback of biofuel use i s that these fuels are used in traditional stoves and furnaces, which are inherently inefficient. It is wel l known that conventional mud stoves operate with thermal efficiencies of the order of 1 0 per cent or less. Nearly 40 per cent of 1 5 m unorganized enterprises consume biofuels in India (Sarvekshana, 1 995) [Unorganized enterprises are those which are not registered under the Smal l

Industries Development Organization of India] . Though, considerable number of registered smal l industries also consumes biofuels, accurate information is not avai lable on the number of such enterprises and the quantum of fuels consumed. Survey of some biomass using enterprises (Kishore and Rastogi, 1 987; Mande et al., 1 999; Mande et al., 2000) and avai lable data show that the end use efficiencies of devices used in such enterprises is also quite low. An estimated 20 mt of biomass is used in traditional rural enterprises (Kishore, 1 999). A partial l i st of biomass usmg enterprises is given in Table 3.

Fossil fuels (Conventional fuels)

Coal production ( 1 995-96)

Lignite production ( 1 994-95)

Total solid fuels

Table 2 - Fossil fuels and B io-resource base of India

B iofuels

Natural gas ( 1 994-95)

LPG produced ( 1 994-95)

LPG i mported

TOlal gas energy

210.0 mt

1 9.5 ml

289.5 mt

1 9.30 bm'

2.80 mt

0.62 mt

0.975 EJ/y ( I EJ = 1 01XJ )

Fuel wood used ( 1 994-95)

Crop residue production ( 1 994-95)

Total

Biogas from cattle dung (potential)

B iogas from sewage (potential)

B iogas from MSW (potential)

Biogas from other wastes (potential)

Total

Total gas energy (ultimate potential)

220 m!

1 60 m!

380.0 m!

36.23 bm'

0.29 bm'

0.24 bm1

0.05 bm'

36.8 bm'

0.693 EJ/y (El = 1 0 1xl )

Source: V V N Kishore, Lecture notes on biogas technology, prepared for Renewable Energy Updating Workshop for MNES Staff, Pondicherry, June 1 997

1 08 J SCI IND RES VOL 62 JANUARY-FEBRUARY 2003

Thus, though the bioresource base of India is substantial , its contribution to usefu l energy is low. An indirect consequence of the low energy use efficiency is that the carbon emissions would be high [Useful energy is the energy that is ultimately used for the end application. For example, in water heating the heat content of hot

water is the useful energy while the heat content in the fuel that was fed is the input energy] . The ratios of carbon content to calorific value of several fuels including biofuels and bioderived fuel s are shown in Figure I (a) and it is apparent that, except for hydrogen rich fuel s l ike natural gas, the carbon emitting potential of al l fuels

Table 3 - Biomass using industries/enterprises in India

Industry

Halwai (khoya making, etc.) Disti l leries Lime making Surkhi Khandsari units Brick making Roof t i le making Potteries Extraction of animal tallows Beedi manufacture Coconut oil production Rice par-boi l ing Hotels, hostels etc. Preparation of plaster of Paris Charcoal making Tyre retreading Soap manufacture Paper and paper board products Rubber sheet smoking Ceramic industry Refractories Bakeries Vanaspati ghee Foundries Fabric printing of sarees and cloth Road t'1rring Fish smoking Tobacco leaf curing*

Tea drying Cardamom curing Si lk reel i ng

Si lk dyeing Cotton dyeing

PulTed rice making

Lead recycling cremations

Specific fuelwood consumption (approximate)

0.34 kg / kg l imestone 0. 1 0. 1 kg 0. 1 kg / kg dry clay

8- 1 0 kg for 1 00 bricks

0.5- 1 .5 kg / kg final product 6 kg / kg tallow

0.075 kg / kg oil O. I kg / kg raw paddy

Not known 4 kg / kg charcoal Not known 250-300 kg / batch of 400-500 kg Not known I kg (per kg fresh latex)

0.7 kg / kg of output 0.67 kg / kg ghce

0.2 kg / m of cloth 23 ton / km

4- 1 0 kg / kg cured tobacco

1 .0 kg / kg dry tea

1 7-25 kg / kg silk yarn

3 - 4 kg / kg of si lk processed I kg / kg of material processed

0.75 kg ! kg of paddy processed

300 kg / body

Total firewood consumption per annum­estimated (number of units)

Not known

Not known Not known

Not known

Not known Not known Not known Not known Not known Not known Not known Not known Not known Not known Not known Not known

Not known 0.63 mt 45,000 t 1 .72 mt 370,000 t 20,000 t 4,38,000 tly (43,000 tobacco barns in Karnataka State, Over 60,000 units in Andhra Pradesh) 0.25 mt annually 75,000 t/y 220,000 tly (25000 cottagelti lature units and 33 ,000 charka reel ing units)

( 1 000 colton processing units in Tiruppur cluster, numbers in other places is not avai lable) 1 20,000 t of paddy husk annually in Karnataka state alone (5,500 in Karnataka) Approximately 1 .7 mt

Source: FAO lIeld document no. 1 8 and Indian wood and biomass energy development project, project document submitted by TERI to FAG, Surveys conducted by TERI , September 1 994

Note: Numbers in the parenthesis are number of units * Firewood is used predominantly in barns in Karnataka, while in Andhra Pradesh, Coal is being used predominantly

Most of the above industries are prevalent i n all parts! slates in India. But, the estimates in some cases are available only in some states

KISHORE & SRINIY AS: B IOFUELS OF INDIA 1 09

Pto(h.cergas eiag_ 0\1'10(_ ."''''''' ....... M LStn stJllks Wood

Nawllgas lPG K ... _ lSHS FlI'receoil

lOO HSD llgrltr.: Co�

0JXlX) OD2lIl 0&100 0D6OO 0DtDl kg C/k'Ml (\tl)

O.100J 0.1200

Figure I (a) - Carbon-CY ratios ( inherent) for various fuels

0.000 0.500 1 .000 1 .500 kg ClkWh (th)

2.000 2.500

Figure I (b) - Carbon-CY r3tios (end usc) for various fuels

is comparable. The rat ios of carbon emissions per unit of 'usefu l energy ' , which take into account the device efficiency [Device efficiency is a part of the overall efticiency of a product. For example, the device efliciency of a cookstove does depend on the type of vessel used. In such case, the device efficiency refers to the efticiency of the vessel that is transferring the heat to the contents in the vessel ] , are shown in Figure I (b) and it is obvious that traditional ly used biofuels emit nearly ten-times more carbon into the atmosphere per unit of useful energy.

One might argue, since biofuel s do not contribute to 'net' carbon emissions the issue of end use energy efficiency is not very important. But considering the fact that biomass is probably harvested unsustainably in some areas of the country and that the national forest cover is substantially lower than the des ired level, more effic ient uti l ization of biomass wi l l definitely enhance the ' s ink' effect of forests. Seen from this angle, b iofuel conservation

should get at least as much importance as afforestation.

A second issue related to b iomass combust ion in traditional devices is concerned with products of i ncomplete combustion (PIC), ch iefly carbon monoxide, methane, total non-methane organic compounds (TNMOC) and N20. These greenhouse gases have higher global warming potentials (GWPs) and it has been shown that their CO2 equivalent contribution is nearly the same as the actual CO2 emitted (Hayes and Smith, 1 994). Results of a study conducted for 28 stove-fuel combinations in India (Smith et al., 2000) c learly establ ish that the currently practiced biomass cycles are not GHG neutral . In fact the study highl ights the win-win s ituation dchievable by promoting use of 'modern' biofuels l ike biogas and producer gas .

3.0 Biomass Conversion Technologies and Processes

An overview of current status of conversion of biomass into useful energy might involve one or more of the fol lowing processes :

( i ) Physical processes, such as reduction, and agglomeration pel letisation)

drying, size (briquett i ng,

( i i) Thermochemical processes, such as direct combustion, pyrolys is and gasification

(iii) B iochemical processes such as fermentation, and biomethanation.

3. 1 Physical Processes

Physical processes are more or less pre­processes. For example, drying and size reduction are important pre-requisites for biomass briquetting and for gasification. The preparation of dung cakes by mixing dung and agro-residues fol lowed by sun drying is an age-old process. Uti l ization of dung cakes for cooking has two disadvantages: First the fert i l izer value of dung is lost and secondly the efficiency of cooking devices (such as Hara, used extensively for s immering of milk in North India) is among the lowest. Also, the burning of dung cakes causes the highest emissions among the biofuels (Smith et al., 2000) . Some attempts have been made to replace dung cakes with briquettes of agro residues, which wi l l be discussed subsequently.

Briquetting of biomass is getting establ ished as an enterprise in India. The growth of briquetting plants in recent years is encouraging. However,

1 1 0 J SCI IND RES VOL 62 JANUARY-FEBRUARY 2003

biomass briquetting is sti l l not wel l understood in a scientific sense and is thus a promising area of R&D. This will also be discussed subsequently.

3. 2 Thermochemical Processes

Thermochemical processes can be broadly classified as combustion, gasification and pyrolysis, depending on the air-fuel ratio, which is highest for combustion and lowest for pyrolysis. Each of the three thermochemical processes, development and conclusions in the Indian context are explained subsequently :

Cookstoves constitute the largest number of combustion devices for biomass, and there is a large variation in traditional stoves. Improving the thermal efficiency of cookstoves and reducing the emissions had been a major concern since the past two decades. The national programme of improved chulhas (NPIC), which was launched in 1 985 by MNES, evokes a somewhat mixed response concerning its success mainly because the benefits are not easi ly quantifiable. A recent review of the projected and realistic benefits of NPIC is provided by Kishore and Ramana (200 I ) . It is increasingly being fel t that improved chulhas are l iked mainly because of their smoke removing capabil ity rather than fuel saving. Though thermal efficiency figures of up to 45 per cent have been reported in laboratory studies (Mukunda et al. 1 988), improved cook stoves seldom gave consistently h igh fuel saving in the field. Cookstoves generally have lower combustion efficiencies and high heat losses, especial ly through flue gases. Scientists have generally adopted fol lowing strategies: ( i) Improve combustion by providing a grate, ( i i ) Reduce flue gas loss by control of combustion air, and ( i i i ) Increase heat transfer by providing more surface (increase the number of pots). Some designs have concentrated on increasing the temperature of fire zone by providing insulation, thereby trying to increase radiative and convective heat transfer to the pot. The control of combustion air is probably the trickiest affair. As al l cookstoves operate on natural draft, and as sufficient opening has to be given for mending the fire and feeding the fuel sticks, the only way to reduce the uncontro lled draft is to provide resistance in the flow path of flue gases. The problem with this strategy is that i t wil l work best for a particular value of burning rate, vessel dimension, etc. (fixed design point) and wi l l fare poorly at off-design operation. As cook stoves can

seldom be operated at a fixed design point, i t is quite difficult to get consistently high performance at all power levels. To design a sol id-fuel burning stove with : (i) High tum down ratio (ratio of maximum and minimum burning rates) ( i i ) High degree of control of air and ( i i i ) High efficiency throughout the range of power levels ; without relying excessively on increasing the heat transfer area and restricting the size and shape of the fuel , i t i s an engineering chal lenge. An early realization of this fact would help in shaping future programmes aimed at conserving firewood.

Improving the efficiency of larger biomass burning systems is far more feasible. Thus, improving the power generation capacity of existing bagasse­burning generation plants in sugar mi l l s by incorporating high-pressure boi lers, was found to be quite feasible.

Consequently, the bagasse cogeneration programme of MNES has been quite successfu l . Power generation from biomass, using fluidized bed boi lers for rice husk, e.g. , has also been reasonably successfu l . The total instal led capacity of power generation based on b iomass combustion is about 34

MW at present (MNES Annual Report 1 999-2000) . The potential power generation capacity, however, is estimated to be 1 7,000 MW.

Biomass gasification is a process that produces a mixture of CO, H2 and methane, CO2 and N2 (cal led 'producer gas ' ) through a combination of thermochemical reactions including the reduction reaction (C02 + C > 2CO), shift reaction (CO + H20 HC02 + H2), the methanation reaction (C + 2H2 -7 CH4), and the water gas reaction (C + H20 -7 CO + H2)' The producer gas has been c lassified as l ow btu gas (calorific value is not general ly constraint for designing h ighly efficient combustion devices or for using the gas in IC engines). Thermal efficiencies of up to 50 per cent (higher if waste heat recovery is done) have been achieved in producer gas burning equipment . As the adiabatic flame temperature, of producer gas is about 1 200°C, i t is general ly thought that i t i s not suitabl e for process heat applications involving h igh temperatures such as brick and t i le manufacturing, steel re-ro l l ing, and l ime boilers But combustion of pre-mixed gases with pre-heated air can produce flame temperatures in excess of I 700°C. Simi larly, power conversion efficiencies comparable to diesel or petrol engines have been obtained in producer gas engines without much derating with

KISHORE & SRINIVAS: B IOFUELS OF INDIA I I I

better control of combustion attainable for gaseous fuels . It is thus possible to achieve high thermal efficiencies and low emissions, thereby making producer gas comparable with petroleum fuels such as furnace oi l , LDO and LPG. The producer gas route of ut i l izing biomass is gaining importance, especially for process heat requirement of small enterprises and for decentralized power generation. These emerging applications are discussed in Section 4.

The programmes of MNES aimed at promotion of gasifiers, however, seem to have achieved only a limited success. A programme launched in the late eighties to promote gasifier-based irrigation pumping systems under a heavi ly subsidized scheme did not take off. S imi larly, i t was found in a survey at a state level that majority of gasifier installations were not in use (TERI Report 1 999) . Nevertheless, interest in biomass gasification, especial ly at the individual entrepreneur level, i s picking up in the recent years .

A major l imitation of gasifier promotion i n India, i s that the designs, which have been developed so far, use only firewood. Though some manufacturers claim to have developed gasifiers operating on rice husk, etc . , there is no evidence to suggest that the systems are operating consistently for long periods and without major operation problems such as water pollution due to c leaning of raw gas. All R&D efforts to develop gasifiers with multifuel capabil ity and for powdery biomass gasification have not yet yielded the desired results .

The third major thermochemical process, pyrolysis, mainly consists of heating biomass to high temperatures with a l imited supply of air, primari ly to ini tiate combustion, and to maintain temperatures required for pyrolysis. For most biomass materials, pyrolysis occurs between 400 to SOODC (biomass characterization, IIT, Delh i ) . The most extensive application of wood pyrolysis is charcoal making. The use of charcoal for applications such as institutional cooking, cloth i roning, CO2 manufacture, beedi processing, lead recovery from used batteries, smithy, and silk yarn re-reel ing appears to be quite extensive, but not well documented. There are over 400,000 unorganized enterprises consuming charcoal for meeting their energy needs in India (Sarvekshana, 1 990) . The most commonly used charcoal producing methods in the developing countries are simple pit kilns and woodpiles covered with earth or vegetation (Vimal and Tyagi, 1 988) . Fairly large chunks of wood are requ ired and carbonization takes from days-

to-weeks depending on the size of the pi le . Typical ly, 8 to 1 2 t of wood is required to produce 1 t of charcoal, using covered-pile methods. S ince charcoal has heat content roughly double then that of air-dry wood on a weight basis (30 GJ/t as opposed to 1 5 GJ/t for air dry wood), the energy efficiency of charcoal production using tradit ional methods is in the range of 1 7 to 29 per cent (Hall et ai. , 1 992). As large chunks of wood are used for charcoal production (as against twigs and branches for cooking), and as these come only by clean fel l ing of trees, one has reasons to assume that almost all the wood going for charcoal making is harvested unsustainably, result ing in thinning of forest cover. The marketing networks for charcoal also seem to have been well establ i shed. Hence, i t i s highly desirable to develop: (i) Charcoal ki lns with h igh effic iency and ( i i ) Charcoal substitution materials (such as char briquettes from agro or forest residues) . Improvements in conversion efficiency can be achieved using more sophisticated ki lns made by brick, concrete or metal . Portable steel ki lns, e.g. , are operational in several African countries. In India also, the Institute of Engineering and Rural Technology (IERT), Allahabad, has designed a portable metal ki ln (Vimal and Tyagi, 1 988) for charcoal production, but it does not seem to have been commercialized . Several large and more sophisticated devices have also been bui lt . These include various continuous ki lns with retorts, which col lect the l iquid products and recycle the gaseous components. Most of them require fairly smal l-sized feed material but are useful for producing charcoal from waste, such as saw dust and bark. Roughly, 60 per cent of the energy in the feed is retained (Bungay, 1 99 1 ) . These plants, however, cost several mi l l ion dollars to bui ld, and are probably not appropriate in Indian conditions. A comparison of the efficiency, cost and l ifetime of some of the main types of charcoal making systems is gi ven by Sinha and Kishore ( 1 99 1 ) .

TERI ( 1 992), has reported use of a downdraft gasifier with a grate-shaking mechanism to produce charcoal continuously, but the technique has not been developed further. A recent i nnovation is the reverse­downdraft gasifier to produce both charcoal and gas, which seems to have promise for rural enterprises. A process for production of charcoal-l ike material, called PARU fuel , had been developed by IIT, Delhi and released for commercial ization, but seems to have fai led as an enterprise. There were some

1 1 2 J SCI IND RES VOL 62 JAN UARY-FEBRUARY 2003

attempts to produce activated char from biomass, which can fetch a h igh price, but these have not been translated into commercial ventures. Process to produce 'pyrolysis-oi ls ' or l iquid fuels from biomass are also avai l able (e.g. in Canada), but these are yet to be commerc ial ized on a large scale.

Incineration is also a variant process of pyrolysis, and has been tried in the past for producing power from munic ipal sol id wastes in Delh i . However, th i s plant never seems to have worked satisfactori ly and has been subject of considerable inter-governmental l i t igation. Surprisingly, there had been very l i ttle discussion on the scientific and technological merits or otherwise of the appl ication of i ncineration process for treating municipal solid wastes.

3.3 Biochemical Processes

Biochemical processes involve the use of microbes and biochemical techniques to produce l iquid or gaseous products (fuels in the context of this paper) from organic matter. One of the most important examples of biochemical processes i s ethanol production .

A variety of crops can be used as feedstock for production of ethanol from fermentable sugar using yeast, such as sugar cane, sweet sorghum, cassava, and various cereal crops (Table 4). The most widely used feedstocks, however, are sugar and starch.

The use of feedstock containing starch and cel lulose for the purpose of ethanol production requi res the conversion of these materials to fermentable sugar fol lowing which the fermentation step yields the desired ethanol grade after the disti l lation process. When grain-containing starch is to be used as feedstock, the preparation for the fermentation process involves enzyme propagation, from starch breakdown to fermentable sugars, fol lowed by the yeast propagation. In comparison, conversion of cellulosic materials to fermentable sugars, the conversion process to starch is fairly simple. Two inherent characteristics of biomass resul t in the problem of converting cellulosic material : cellulose is difficult to convert to glucose sugars which are easy to convert to ethanol whereas hemicelluloses can be easily converted to xylose is difficult to ferment to ethanol (Department of Energy, 1 990).

The process of ethanol fermentation involves the conversion of s imple sugars to ethanol and carbon dioxide by yeasts. B iochemical ly, i t is h ighly efficient and v irtually al l energy in the sugar retained in the ethanol produced (Hal l et al., 1 982). Removal of ethanol from fermentation broth is usually performed using disti l l ation techniques, which is an energy­intensive step since the maximum concentration of ethanol obtained from the broth is only in the range of 1 0 to 20 per cent.

When sugar crops, such as sweet sorghum and sugarcane are used for ethanol production, sugary

Table 4 - Ethanol yields from selected biomass carbohydrate rich plants

Raw material

Beet

Sugarcane

Maize

Wheat

Barley

Grain sorghum

Potatoes

Sweet Potatoes

Ligno-cell ulosic raw material

Soft wood

Dilute acids

Concentrated acids

Hard wood

Dilute acids

Concentrated acids

Straw

Dilute acids Concentrated acids

Source: Adapted from OECD, 1 984

Possible production (tlha)

40-50 SO- I OO

4-8 2-S 2-4 2-S

20-30 1 0-20

Dry matter tlha

9- I S 9- I S

9- I S 9 · I S

I .S-3.S I .S-3.S

Carbohydrate content (per cent)

1 6 1 3 60 62 5 2 70 1 8 26

Ethanol yields (Ut)

90- 1 00 60-80

360-400 370-420 3 1 0-3S0 330-370 1 00- 1 20 1 40- 1 70

Ethanol yields Ut

1 90-220 230-270

1 60- 1 80 1 90-220

1 40- 1 60 1 60- 1 80

KISHORE & SRINIV AS: B IOFUELS OF INDIA 1 1 3

JUIces can be tapped from the plant and fermented directly. After extraction the bagasse residue can be burnt to fuel subsequent dist i l lation steps.

Starch crops, such as cassava and cereal crops, can also be used, although the starch must be broken down to s imple sugars before fermentation, using the sacharification process. This involves mixing the substrate with water, heating it and then subjecting it to enzymic hydrolysis. Because starch crops produce no byproduct that is equivalent to sugarcane bagasse, an external energy source is required to fuel the distil lation process. The use of other renewables, such as wood from plantations and use of solar energy (as the boi ling point of ethanol is 78°C, the use of solar dist i l lation is possible) is the logical solution to this problem. If oi l were used the amount of energy required would be equivalent to the quantity of ethanol produced.

Sugar and starch crops for ethanol production have potential in regions where large areas of reasonably ferti le land are under-util ized. Sugarcane and sweet sorghum are the main examples of crops contatntng sugar. Undcr suitable agro-cl imatic conditions, using modern agricultural methods, these crops yield up to 50 and 35 tlha, respectively . Moreover the sugars they contain are directly fermentable to ethanol and yield bagasse as a byproduct. Bagasse can be used as a fuel for the energy-intensive ethanol dist i l lation process, thereby improving the overal l energy balance. The main disadvantage of these crops (particularly sugarcane) is that they require land and adequate i rrigation for high yields (Hall et al., 1 982; Vimal and Tyagi, \ 988) .

The primary starch crop of interest is cassava. Though a variety of other plants such as sweet potatoes, corn, rice and other cereals can be converted to ethanol, but their value as foodstuffs makes them unavai lable for ethanol production. Cassava has the advantage of being tolerant to poor soi l and adverse weather conditions. Another potential feedstock for ethanol production is surplus molasses from existing sugar production fac i l ities. Every tonne of cane sugar produced, results in approximately 1 90 L of molasses as a byproduct. This contains 50-55 per cent fermentable sugars and yields about 280 L of ethanol per tonne of molasses when fermented (Hall et ai., 1 982) . Only in remote sugar production faci l ities (where i t is wasted because of high transportation costs) does converting molasses to ethanol appear

feasible. In India, molasses is a valuable input to the chemical industry and therefore may not be avai lable for alternate uses (Vimal and Tyagi , 1 988) .

As mentioned earl ier the conversion of woody biomass and grasses with sign ificant cellu losic and hemicel lu losic material to ethanol is a difficult process. S ignificant R&D efforts are being devoted to improve conversion processes to increase the yields of ethanol, using such feedstocks. The US Department of Energy, e .g . , hopes to achieve the overall goal of producing ethanol at $ 0. 1 4/L by the turn of the century. The 1 989, production cost was placed at $ 0.32/L, whereas the 1 979 production cost was $ 0.86/L (DOE, 1 990).

The use of ethanol as a source of energy is, however, a debatable issue in the Indian context, as it does not appear to be economical . Detai led techno­economical calculations are yet to be made to examine the feasibi l ity of using ethanol as a blend of petrol or for use in advanced power generation system such as fuel cells . The contribution of ethanol production with a decentralized power plant would appear attractive, as the waste hcat can be gainful ly used tn the disti l lation process. Such smal l , decentralized 'cogeneration' systems wi l l be discussed later.

The second most important biochemical process in the Indian context is anaerobic digestion, or biomethanation. As mentioned earl ier, India has a huge cattle-dung resource, which is highly adaptable for biogas production. Anaerobic digestion involves complex biochemical reactions, but these can broadly be c lassified as acidification reactions and methanation reactions. The complex molecules of biomass are first broken down to simple molecules ; chiefly acetic acid in the first step and methane is produced from acids in the second step . The kinetics of methane production is highly dependent on temperature, methanogen concentration, and pH. B iogas reactors can range from a deceptively simple brick and concrete digester to using cattle dung to highly compl icated UASB (Up flow Anaerobic Sludge B lanket) reactors processing industrial effluent to produce methane. The hydrau lic retention t ime, and thus the volume of the reactor, can vary from 1 00 d (for a rural biogas plant in a cold, north Indian h i l ly region) to 24 h (for a UASB reactor with well formed granules) .

Considering the potential in the country, MNES launched several programmes to promote

1 1 4 J SCI I ND RES VOL 62 JANUARY -FEBRUARY 2003

biomethanation technology quite early . The earliest (and probably the largest t i l l a few years ago from resource al location point) in the National Programme for Biogas Development (NPBD) aimed at promoting biogas plants in rural areas for ut i l izing the available cattle dung.

The latest is to promote biomethanation of urban and industrial wastes, aided by UNDP/GEF, with financial outlay of about 6 m dol lars.

The number of biogas plants installed so far is about 2 .9 mil l ion, second only to China . By al l official counts, the NPBD is a success, but the programme is general ly criticized for being dependent solely on government support. At the rate at which biogas plants are instal led (even without taking into account the plants becoming non­functional for a variety of reasons), i t would take several decades to real ize the fu l l potential of using cattle dung in rural areas. In spite of the enormous promise, biogas technology has for rural economy; the whole programme appears to be heading for a lame tapering-off. This can probably be attributed to the fai lure of MNES to integrate R&D, technology, entrepreneurship, and financing and social dynamics into a powerful programme focusing on business development opportunities. The extremely l imi ted R&D efforts concentrated primari ly on microbiological studies and even there, no effective l inkage was established between laboratory work and field implementation.

The simple biogas digester, just l ike the simple chulha, seems to be eluding rigorous scientific analysis that can lead to an optimal design. In spite of a number of separate studies on microbial kinetics, residence t ime di stribution studies (Raman et at., 1 988) heat transfer analysis ( Kishore, 1 989) and even rheological studies, a chemical reactor model of the biogas plant has not been developed so far. While the theoretical possibi l ity exists that hydraul ic retention time (HRT) of a few days is possible from kinetic consideration, the actual HRT remains at 40 d and in spite of so many advances in materials, cement, brick and metal continue to be the chief constructing materials .

On the other hand, based on R&D carried out in advanced countries, chiefly The Netherlands, concepts such as UASB have evolved and have been applied for biomethanation of disti l lery effluents, tannery effluents, sewage etc. However, no suitable h igh rate, or even medium rate, technology has been

developed for solid organic residues l ike municipal solid waste (MSW), industrial solid wastes, cattle dung, and poultry waste. A biphasic process involving enhanced acidification, fol lowed by methanation in a UASB reactor has been recently developed (Rajeshwari et at. , 2000) but it is yet to be upscaled and field tested.

Composting is also an important biochemical process. Based on the work done by Excel industries, some plants have been constructed to produce rich organic manure from MSW in recent years . However, as these plants rely on a lot of open area, which becomes a problem during monsoon, they seem to have met only a l imited success. Reactor composting would be qui te convenient for several residues (e.g. hotel wastes), but no such work has been initiated so far.

In conclusion, i t appears that there are sti l l l argely unexplored or underexplored areas for R&D, product development, process development etc. in the broad area of biomass ut i l ization and that there has been very l i tt le overlap between field based 'national ' programmes, development of product and technology and dissemination .

4.0 Modern Biomass Utilization: Some Emerging End Uses and Research Needs

Modern biomass ut i l ization hinges on using efficient and environmental ly friendly technologies for conversion of biomass to more convenient forms . In the Indian context, these technologies can be l i sted as fol lows:

• Biomass briquetting/pel letisation.

• Effic ient charcoal making from wood/biomass residues.

• B iomass gasification.

• Advanced biomethanation.

A host of supporting technologies/systems wi l l a l so be required to make ful l benefit of the conversion technologies. Some of these are :

• A variety of drying equipment for use with different materials to be dried.

• Size reduction and agglomeration machinery .

• Cool ing/cleaning systems for producer gas with particular emphasis on low maintenance and l ong l ife .

• Efficient producer gas engines capable of operating on gas alone.

. lo.

KISHORE & SRINIV AS: BIOFUELS OF INDIA 1 1 5

• Optimal or low cost gas storage systems.

• Efficient blowers, compressors, etc .

• Efficient gas burners. • Smal ler capacity waste heat recovery systems.

• Low capacity absorption/adsorption cooling systems operating on waste heat and/or producer gas.

• Control systems for gas flow.

A combination of the above systems/subsystems can be gainful ly employed to tackle a variety of appl ications ranging from process heat in industries to small power generation in rural areas . An attempt is made to classify the promising end uses and outl ine the underlying research needs.

4. 1 Biomass as a Substitute to Fossil Fuels

Whenever there is an increase in the prices of petroleum fuels the demand for alternative fuels/energy hots up. The last few years witnessed such increase in prices and there are chances that the scenario might repeat. The last few years also saw an increase in demand for biomass briquettes, conversion of oi l-fired devices to wood or b iomass fired devices, co-firing of b iomass with coal . The significance of biomass l ies in the economies, as shown in Figu re 2 . It can be seen that producer gas from biomass (wood or briquettes) is an extremely attractive option for process heat as compared with petroleum derived fuels. As firewood is not a desirable option i n the long run from sustainabi l ity point of view, biomass briquetting would become an important topic in the coming years.

.� r.n:�':'=, -- --I I

One of the major problems dogging the briquetting industry is the wear and tear of machine parts such as the ram, taper die, wear ring, split die, etc . Due to the need for constantly replacing the worn out parts, briquetting plants operate at a low capacity uti l i zation factor of about 28 per cent (Pachauri et al., 1 994) . Attempts in the past to solve this problem by using different materials for the wearing out parts yielded only a l imited success . It was also observed that heating biomass or the die reduced wear and tear (Joshi et al., 1 994) . The important point to be noted is that the best scientific and technical minds of the country have perhaps not appl ied their minds to the problems of the industry. The small entrepreneurs, with their l imited scientific ski l l s have done an excellent job of finding low cost solutions in a difficult trial and error process to sustain the enterprise. In order to pump some advanced knowledge i nto briquetting, a smal l project was recently granted to an entrepreneur in Maharashtra by the Home Grown Technology (HGT) programme of DSIR (Department of Scientific and Industrial Research). In this project, advanced coating techniques are being tried to improve the l ife of the crucial machine parts.

Another problem facing briquetting industry is that briquettes form wel l with sawdust alone. Even though other biomass can be used, sawdust is a necessary ingredient (at least 50 per cent) . This poses a severe constraint on the industry, as major agro­residues such as bagasse, rice husk, coir pith etc . wil l

Vil lage

---

5

1 . screw feeder 2 . gasifier 3 . gas cleaner 4 . fan 5 . g as holder 6 . g as users

Figure 2 - The vi l lage biomass gas supplying system

1 1 6 J sel lND RES VOL 62 JANUARY-FEBRUARY 2003

have to be left out of briquetting. The pecul iar problems of biomass briquetting seem to warrant an indepth scientific and engineering research, which has not been init iated even after two decades of briquetting in India.

Briquetting plants are located in rural areas for logistic reasons, but power supply is an acute problem in these areas. There is no easy solution for this problem. An approach suggested long back is to instal l a gasifier-based power p lant for powering the briquetting machine, and sel l both power and briquettes. However, there are no rel iable gasifiers that can take briquettes as fuel (briquettes are known to cause c l inker problems in gasifiers) and the idea could never be tried.

Briquettes also do not burn efficiently in furnaces, which were originally designed, and for coal and burning of briquettes may not be environmental ly sound. Al l these i ssues can be examined in detail if there is a comprehensive and multidiscipl inary programme aimed at large-scale promotion of briquetting enterprise.

Pel letisation is an alternative to briquetting. It involves pulverization, steaming, and addition of a binder and extrusion of pel lets. Pel letisation takes place at a lower pressure and hence problems of wear and tear are drasticall y reduced. Another ongoing project of HGT is studying different technical aspects of pel letisation . The drawbacks of pel letisation are the need to add a binder, such as molasses and the stabi l ity and shelf- l ife of pel lets, which are known to disintegrate easi ly. As mentioned earl ier the problems of briquetting and pel letisation are complex and would need a multidisciplinary approach.

One important socio-economic aspects of briquetting is that, nearly 30 per cent of the production cost of briquettes, which goes towards biomass procurement, is ploughed back to rural areas where employment opportunities other than agricul ture are quite meager. Thus, briquetting can, in principle, he lp in creation of wealth in rural areas.

Biomass, such as firewood obtained sustainably from plantation (e.g. rubber plantations), coconut shel ls , and cashew shel ls can probably be directly used in sui table gasifier systems to replace fuel oil or d iesel . However, experience suggests (Kishore, 200 1 ) that a gasifier system cannot be just added into an existing end use, but considerable effort goes for ' integrating' the gasifier with an appl ication. Thus, development of a complete end use package, which

might involve modifications of some components in the existing system, i s very important to ensure successful integration. The costs for such field-based R&D-cum-demonstration are usual ly quite high and cannot be afforded by the entrepreneur. Hence, there is a need to take up such projects for a variety of industries such as crumb rubber manufacture, tea drying, coffee processing, food processing, l ime ki lns, mini-cement plants, lead recovery from used batteries, aluminium and brass melting and wire enamel ing. In some enterprises such as tea processing, there is also a good scope for introducing smal l cogeneration systems (Mande and Kishore, 1 997), resulting in a much better uti l ization of biomass.

4.2 Biomassfor Development ofRural lnfrastruclure

Biomass technologies for decentral ized power generation can be categorized as fol lows:

• Direct burning of biomass to run steam turbines.

• Direct burning of biomass to run sterl ing engines.

• Gasification of biomass to run Ie engines and combined cycle systems.

• Biogas production from cattle dung to run Ie engines.

• Misce l laneous technologies for producing l iquid fuel (bio-alcohol , bio-diese l , pyrolit ic oil) to run Ie engines.

Earlier attempts of projects related to 'd irect burning' of biomass, such as the dendothermal power plants in Phi l ippines (Kishore and Thukral, 1 993) fai led probably due to a combination of factors related to technology maturity, b iomass col lection, organizational set up, and funding. B iomass fired stirl ing engine system (Kishore and S inha, 1 99 1 ) seemed a sound technology option for smal l power generation « 25 kW) for isolated rural communities and for i rrigation pumping. Lack of financial support for technology improvements and market deVelopment resulted in closing down of the enterprise.

The first tried out option for smal l v i l lage power was the biogas system. The community biogas concept in which cooking gas was produced in a decentral ized manner and distributed to households and part of the gas used for power generation was a highly relevant local init iative. But as there were no efforts on technology upgradation (for example, in

KISHORE & SRINIV AS: BIOFUELS OF INDIA 1 1 7

the direction of developing high rate reactors, dry digestion etc . ) and enterprise development, the community biogas concept degenerated into a government run programme and is finally abandoned. But the concept can be revived in view of the recent advances in anaerobic digestion. Processes, such as those described by Rajeshwari et ai. (2000), can be scaled up, demonstrated at a v i l lage level through entrepreneurial efforts for production of power, cooking gas and manure on commercial or semi­commercial l ines. Or the community biogas plant can itself be upgraded and revamped to involve entrepreneu rs.

A project aiming to uti l ize oil from non-edible oi l seeds as a substitute for diesel has recently been initiated in the state of Karnataka, but there is not enough field experience and operational data to evaluate such a process for technical and economic viabi l ity. Processes for producing pyrolytic oil from biomass are avai lable, e .g. , at B iomass Technology Group (BTG), University of Twente, The Netherlands and a proposal to use such oi ls for gas turbine operation has been mooted by a Canadian company. Such projects are yet to be evaluated for detai led techno-economic feasibi l ity studies.

There are two problems preventing v i l lage power ventures from becoming success stories commercial . The first one is related to plant load uti l ization and the second to the purchasing power of rural people. The cost of power generation, apart from other factors, depends critically on the plant load factor or the number of hours of operation per year at the rated load . Figure 3 shows the variation of different cost components with the number of hours of operation for a typical gasifier-based dual fuel power plant. It can be seen that, while the diesel and biomass costs remain more or less constant, the Operation, Maintenance and Repair (OMR) and interest costs per unit of electricity generated are quite high at low plant usage hours . And yet, this i s typically the case for rural loads where l ighting load is low, pumping load is seasonal and no industrial load centers exist. Thus the final cost of e lectricity generated wou ld tend to be high. On the other hand, the purchasing power of rural people is quite low in many areas as they are dependent primari ly on agriculture. Also, electric ity had been subsidized heavily for rural areas and hence people are accustomed to pay very l ittle for it. This s ituation, however, i s changing slowly due to electric power

Reliability, material optimization, competitiveness

laboratory Field Commercial Final

prototype prototype prototype product

laboratory development

Field testing

Industrial Action Commercial design research ' deployment

Currently proposed R&D funding

Time -+

l Credit

4

Financial support for monitoring and evaluation

Figure 3 - Trajectory of indigenous technology development

regulatory bodies and several state governments are convinced about the need to raise tariffs . It is thus imperative that any power producer operating in rural areas cannot restrict to supply of e lectricity alone, and wil l have to expand the services offered, so that extra income is generated. Some of the operations which have the potential to increase the profitabil ity of a rural energy enterprise and which would help in improving rural infrastructure at the same time are:

• Establ ishing a briquetting plant.

• Supply of cooking gas .

• Making of char briquettes.

• Cold storage for agricul ture produce.

• Crop drying.

• Desal ination to provide drinking water.

The advantages of setting up briquetting plants have already been discussed. In the context of rural power generation, a briquetting plant would serve to increase the load in factory considerably .

Supply of cooking gas through the biometha­nation route has already been mentioned earlier, but it is also possible to supply piped producer gas for cooking. A scheme for such a rrocess is shown in Figure 2 and more than 65 such instal lations have been establ ished in China (Sun et ai., 1 995) . There are several advantages of getting into the business of cooking gas supply. First, it has a direct bearing on the qual ity of l ife and removes the drudgery of women. Secondly, it frees biomass from being inefficiently used and thus makes it avai lable for

1 1 8 J sel lND RES VOL 62 JANUARY-FEBRUARY 2003

power generation. A conceptual scheme of how the biomass burnt at present in traditional stoves can be used for providing both cooking gas and electricity at the national level is shown in Figure 4. It is evident that by fol lowing the gasifier route, not only all the cooking energy requirements are met, but also enough biomass would be available to generate 1 25 bi l l ion kWh of electricity. The current demand in rural areas is not even half of this amount.

The useful energy util i zed for the purpose of cooking is based on the current firewood consumption of 220 mt/y (TEDDY, 2000/200 1 ) and

the traditional oven is assumed to operate at an efficiency of about 1 0 per cent (though it is lower .-l­than this number in many cases). This would produce a useful energy of 88 x 1 0 1 2 kcals of thermal energy. If the biomass is used through the route of gasification, at a conversion efficiency of about 70 per cent (wood to gas) and the device efficiency of 50 per cent (other than the gasification, the burner effic iency, etc .), it would not only meet all the cooking energy requirements (same useful energy) but also wi l l be able to produce about 1 25 b kWh of electricity additional ly . Additionally, if some form of

220 million tons/year of firewood

Traditional route ( 1 0% efficiency)

88 x 1 012 kcal of useful energy

880 X 1012 kcal of wood energy

1 76 x 1012 kcal for cooking

Gasifier route

605 x 1012 kcal of gas energy

429 X 101 2 kcal for power generation

50% efficiency 25% efficiency

88 X 1 01 2 kcal of useful energy for cooking

125 billion kW11e (- 24,000 MW @ 0.6

PLF)

Figure 4 - A conceptual scheme for generating cooking gas and electricity from the same amount of tirewood used at present traditional l y

"

KISHORE & SRINIV AS: BIOFUELS OF INDIA 1 1 9

cogeneration is integrated to get process heat as well as electricity, would further, benefit the situation either in reducing the fuel consumed or wi l l be able to meet energy needs in other forms.

If a biogas plant is operated in the same complex, as the gasifier power plant the waste heat from the engine can also be used which i ncreases the operating temperature of the b iogas plant, thus increasing the gas production rates. There are several other ways of using the waste heat. It can be used to run a cold storage operating on the absorption (ammonia-water) or adsorption (methanol-sil ica gel) Mande et at., 1 997) systems. If necessary, the waste heat can be supplemented by burning part of the gas . There is a severe shortage of cold storages in the country leading to spoilage of fruits and vegetables, resulting in distress sales by farmers . The usual practice is to rent out cold storage space on a dai ly or weekly rate. Operation of cold storages thus provides additional income to the power plant besides increas ing the overall efficiency significantly.

The other post-harvest operation in rural areas is drying. Crop drying is presently done by open sun drying, leading to inefficient moisture removal, fungus infect ion etc . Crops need drying temperatures in the range of 55-80°C, which can be easily obtained from engine exhaust by using a gas-air heat exchanger. Recent experience of using gasifiers for cardamom curing in S ikkim showed that, not only drying times are reduced, but also the quality of the dried product is superior, fetching a h igher price in the market. When the demand for drying is h igh in drying season, gas can be used directly for burning to augment the available waste heat.

Many v i l lages in India suffer from chronic draught, which aggravates if monsoons fai l . Some of these vi l lages, especial ly in Gujarat state, have brackish water, which is not fi t for drinking purposes. A multistage flash (MSF) dist i l lation system can be used to produce drinking water from brackish water. Though the avai l able MSF systems are too large to be used in a decentral ized manner, a 3-or 4-stage system can be eas i ly developed for such appl ications. MSF systems also require temperatures of about 1 00°C, which can be obtained from waste heat . Another alternat ive is to use membrane systems for reverse osmosis to produce drinking water. These wil l need power and hence can be employed as load centres.

A strong case thus exists for a rural power company to expand its services several-fold, so that any loss in the sel l ing of power i s offset by profits i n other streams . Several thousands of such companies, operating with a basket of devices and technologies, can be set up throughout the countryside as a cha in . Such a chain of companies would require the fol lowing i nputs for steady , profi t making operat ion :

• Quality technical and R&D inputs from established institutes .

• A h igh level of system integration to optimize operations.

• Mechanisms to ensure supply of biomass and sale of power and other goods and services.

• Financing schemes at low interest rates both for in itial and working capitals .

• Established NGOs (Non governmental organizations) with a good trace record can also get i nvolved in these activities.

5.0 The Importance of Product Development, Manufacturer and Market Network for Rural and Small Enterprises

In conventional sense, ' i ndustrial research' involves either an R&D institute developing and transferring the technology of a product/process to the industry or an establ ished i ndustry developing products/processes for i ts own upgradation through in-house R&D or col laboration. The funding patterns for such R&D activities are also wel l established . For small and rural enterprises, however, such conventional scientific wisdom may not work.

The difference between the current practice of funding and a 'desirable' funding pattern is explained in Figure 4 (Kishore et at., 200 I , ed. Vipradas) . Figure 4 projects a des ired trajectory of indigenous technology development with t ime as X-axis and development in the Y-ax is to arrive at the matured product. Generally the development starts with the evolution of an idea that gets transformed into a laboratory prototype, which gets R & D funding. In many cases, the support may continue up to the development of a field prototype testing. Normal ly the funds stop almost abruptly as soon as a laboratory prototype or proof-of-concept system is demonstrated. It is general ly assumed that the process of transformation of a laboratory prototype into an industrial product is the job of the entrepreneur. But

1 20 J SCI [NO RES VOL 62 JANUARY-FEBRUARY 2003

the rural and small entrepreneurs are i l l equipped to carry out this task. In most cases, alternate energy devices are diffusely spread and its uti l ization is problem specific . Here, a laboratory demonstration of a concept should not be end of the project. The product has to be successfully interpreted (from industrial design, manufacturers and also from users point of view) at the end user level with economic implications. The product should be rel iable [Reliability

i s the abi l ity of a product to deliver what i t is designed for

consistently] , material optimization (proper selection of material and cost-effective) [Material optimization - Often

new products specifically al ternate energy devices that are at

proof-of-concept stage sutler from proper material selection and

use of appropriate quantum material that have implications on l i fe

of the product and also on the cost] and competitive [The

choice of a product in most cases is compared to the costs of

cxisting {current product. Hence, thc costing should consider this

aspect to be competitive] to existing practices. Attempts to promote alternative energy devices, such as gasifier based pumping systems in India which did not take off at the desired level perhaps also due to some of the above problems .

An i l lustration, where some of the above mentioned problems were addressed, involves a product development for the s i lk reel ing [An activity where the cocoons arc cooked and reeled to get silk yarn. The owner of such a unit is generally called as 'reeler' ] industry and is shown in Figure 5 . It has been shown (Suni l et al. , 200 I , ed. Vipradas) that the viabi l i ty, user­friendl iness, l ife, etc. of the product keeps improving from stage-to-stage, until i t becomes strong enough to enter and sustain the market environment. Substantial ground works in developing product based on gasifier for cocoon cooking was undertaken before the actual intervention was des igned. Considerable care was taken in reaching the product to maturity with appropriate inputs from various stakeholders (from users, subject experts, design consultants, manufacturers and backstoppers [Consultants who had the mandate to see to i t that the programme is meeting its designed goal and the activities arc running as per plan and schedule. [n addition, they were also involved in technical assessment of the project apart from other aspects the project]) . Though, original premise for using the gasifier based system cocoon cooking was, to reduce the fuel consumption and improve the working condition, due to lesser pol lution in the reel ing unit, there were several other benefits. These i nc lude reduction in renditta (renditta is a term general ly used in s i lk industry essentially

Annual monetary �ng (Rs '000 per year) r-:--:-:------, 300 Fuel �ng(%) 75

250 70

200 65

60 150

55

100 50

50 45

o�--����-----------+ 40

Phase-I Phase-II Phase-III

June 1994 September 1995 December 1996

- Annual monetary Saving (Rs/year) \f 1) ._-- Fuel saving % \f 2)

Test markeUng

June 1998

Figure 5 - Different stages of development with total monetary benefits (SDC-TERI experience on product development)

means quantity of cocoons requi red to produce one kg of s i lk) , improvement in the qual i ty of s i lk produced due to better processi ng conditions (consistent heat from gasifier based burner when compared to traditional oven), increased processing rate (which could result in saving of labour to do certain work or to increase the quantity of material processed) and also reduction in water consumed. The annual monetary savings due to these improvements are given in Figure 5 and the fuel savings in subsequent models of gasifier based ovens.

Marketing is another important issue to be understood during the product development stage i tself. Almost any product can be pushed into an artificial 'market ' , aided by subsidies, but i t i s an extremely difficult task to market a new product in rural areas and in non-consumer market segment. Identification and selection of manufacturers, ensuring qual ity control, establ ishing the chain of l inkages both for sales and services, all require financial support, which is not avai lable at present, both to the scientist and to the small entrepreneur.

6.0 Conclusions

The biomass resource base of India i s comparable to that of fossi l fuels . But factors, such as col lection, processing, low end-use efficiency of conventional devices, and insufficient maturity of

.4_

KISHORE & SRINIY AS: BIOFUELS OF INDIA 1 2 1

present b iomass energy technologies are major barriers for uti l izing the available bioresources more efficiently and on a sustainable basis . A review of the present status of biomass conversion and uti l ization technologies reveals that there is a large scope for launching major R&D and product development initiatives for promotion of efficient use of biomass. Uti l ization of a basket of energy technologies, rather than a single technology to del iver energy and economic services in rural areas seems to hold the key for successful commercial ization and mainstreaming of biomass energy technologies. The R&D strategy and funding pattern for development of products/processes/technologies based on biomass for the benefit of small and rural enterprises wi l l necessari ly have to fol low an unconventional approach.

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Kishore Y Y N & Rastogi S K. Thermal analysis of cardamom curing chambers. Ener Agric, 6 ( 1 989) 245-253.

Kishore Y Y N, Ranga Rao Y Y & Raman p, Some problems of implementation of biogas technology in rural areas, Tata Energy Research Institute, New Delhi [TERIIDP/O I /86j 1 986.

Mande Sanjay, Pai B R & Kishore Y Y N, Study of stoves used in si lk reeling industry, Biomass Bioener An l11t .I, (2000) .

Mande Sanjay, Kumar A & Kishore Y Y N, A study of large­cardamom curing chambers in Sikkim, Biomass Bioener, 16 ( 1 999) 463-473.

Mande Sanjay, Kishore Y Y N, Kai Oertel & Uwe Sprengcl, Advanced solar-hybrid adsorption cool ing system for decentralized storage of agricultural products in India, Pro. CLlMA-2000 '97, Brussels (August-September 1 997).

Mintstry of Non-conventional Energy Sources, Government of India, Annual Report 1 999-2000. Mukunda H S . Shrinivasa U & Dasappa S , Portable single-pan wood stoves of high efficiency for domestic use, Sadhana, 13 (Part 4) (December 1 988) 237-270.

Pachauri R K, Dwivedi B N, Joshi Y, K ishore Y Y N & Kanctkar Rajshree S , Indian wood and biomass energy development project, Project Document ( 1 994- I 999), submitted to Food and Agriculture Organisation of the United Nations, September, 1 994.

Pal R C & Joshi Y, Field evaluation of improved cookstoves, Renewable energy rural development, edited by Y Y N Kishore and N K Bansal (Tata Mc Graw-Hi l l , New Delhi) 1 989, 3 1 8-323.

Rajvanshi A K Dis/illation of ethyl alcohol from fermented sweet sorghum using solar energy. Report submitted to th� Department of Non-conventional Energy Sources (by Nimbkar Agricultural Research Institute, Phaltan, India, 1 984.

Rajeshwari K Y, Pant D C, Lata K & Kishore Y Y N, A novel process of using enhanced acidification and a UASB

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reactor for biomelhanation of vegetable market waste, Waste Manage Res (2002) (accepted) .

Raman P, Sujata K, Dasgupta S & Kishore V V N, Residence Time distribution studies of biogas digester models, Paper presented at the National Solar Energy Convention '88. Hyderabad, December, 1 988.

Tata Energy Research Institute. Potential for utilisation of biomass gasifier systems in plantation and related industries. Report submitted to the Department of Non­Conventional Energy Sources, 1 992.

Tata Energy Research Institute, TEDDY (TERI Energy Data Directory & Yearbook) 20001200 I .

Ravindranath N H & Hal l 0 0, Biomass, energy, and environment - A developing cOlin II)' perspective froll! India (Oxford University Press, UK) 1 995.

Sinha Chandra Shekhar & Kishore V V N, B io-fuel conversion processes and technologies. TERI Inform Dig on Ener. (Jan. to Mar. 1 99 1 ) .

Smith K R, Dialectics of improved stoves, Ecuno Pol Week, 24( I 0) ( 1 989) 5 1 7-522.

Srinivas S N , July 2000. Biomass consumption i n unorganised enterprises in India, Biomass Users Network, 3.3 (July 2000) (2000) 2-4.

Survey o/" unorganised manufacturing sector, NSS 45'h Round. National Sample Survey Organization. Department o/" Statistics, Government o/" India, Sarvekshana, 19 (No. I ) (July-September 1 995) 64'h isslle.

United States Agency for International Development (USAID), Lowering exposure of children to indoor A ir pollution to prevent ARI: The need for in/ormation and actioll. environmental health project - Capsule Report. Number 3, January 1 999.

Verhaart P, On designing woodstoves, Proc Indian Acnd 0/ Sci (Eng Sci). 5 ( 1 982) 287-326

Vimal 0 P & Tyagi P 0, Bioenergy spectrum, New Delhi: BioEnergy and Waste/aul Development OrgallisatlOll, Chemistry Department anJ Indian I nstitute of Technology, 1 988.

Vimal 0 P & Tyagi P 0, Energy }i'O/1/ biomass (Agricol Publishers, New Delh i ) 1 985.

Dr Kishore has 22 years of expertise in the areas of biomass IItilization, waste-to-cnergy systems, and solar energy applications. His main work experience consists of develof/ment of products, processes, and end-use packages, starting fro/ll conceptllalization and prototype development t17 [teld-testing, tramfer of technology and identification o/market linkages. He led a grollp of professionals at TERI who successflllly developed and commercialized biomass gasifier for a variety of applications, such as sericulture, textile dyeing, illSlitlltiollal cooking, cardal/lom cllring, and rubber drying, and for decentralized power generation for remote areas. Nearly 250 TER I gasifier systems for a variety of end-llses have beelt illStalled throughollt the cOllntry hoth IInder demfmstration-cllm action research projects supported by governmelll departments and

bilaleral agencies and commercially throllgh manufactllrers to whom the technology is transferred. Dr Kishore has developed a process of generating energy and manure from wastes, S/Ich as vegetable market wastes, food liroccssing wasles, and other organic wastes hy means (!f a hiphasic process termed TER!

,s Enhanced Acidification and

Methallation (TEAM) process. He has led a team, which designed, cOllstructed and operated Asia's largest solar Iiond (6000 1Il2) for supply of process heat to a dairy ill KlItch in north-west India. Earlier, he was illstrumental in developing the TERI model of rural hiogas plant, a mohile hriquelling-gasification system for rural areas. passive solar systems for cOlllfort conditioning in composite clim{/te.�, shallow solar pond system for domestic I/Ot water and solar ( thermal) water pump. He also led a group for studying greenhouse gas emissions from small hiomass comhllstion devices ill. India IInder a collahoralive project with East West Centrr., Hawaii. He has execl/ted several other projects, which involved policy analysis, laboratory work and exteltsive field lVork. He has pllblished over 150 Ilapers in scientific and technical jollrnals, edited 5 books, and holds six patents. Dr Kishore is a Chemical Engineer lVith {/ doctoral degree from the Indian Instilllte of Tec/ulOlogy, Kanpur. He is currently a Senior Fellow and Resource Advisor at TERI and is involved in several ongoing projects in biomass and waste utilization, and ill projects dealillg I Ilith climate change i.Hues, renelvllhle energy policy, and energy efficiency improvement in rural and small 1'lIIerprises. He also holds the additional charge of the Centre of Energy and Environment ill the FaCilIty of Applied Sciences, TERI School of Advanced Stlldies, which has a deemed university slatus. He acted as the Dean of Energy t;ngineering Division of TERI during 1 990- 1 992. Before joining TERI ill 1 984, he was working in the Central Salt and Marine Chemicals Research Institllte of CSIR. He has acted as a chaillJersOIl and member of several commillees of the Ministry of Non-conventional Energy Sources (MNES), Department of Science and Technology, Council of Scientific alld Indllstrial Research etc. Currently, he is a member of the Slanding Monitoring and Review Commiuee of Gasifier Aclion Re.w'arch Project (GAR?) of MNES alld Monitoring Committee for the project on 5 and 25 kW decentralized power packs under New Millenium India Technology Leadership Initiative (NMITU), launched by CSIR. He is the rccipielll of Dr KS Rao Memorial award given hy the Solar Energy Society of Illdia, for the year 200 I.

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KISHORE & SRINIV AS: BIOFUELS OF INDIA

Mr Srinivas has 12 years of experience in the demonstration and dissemination (�l energy efficient and renewahle energy technologies, spec!fically hiomass energy systems, evaluation of renewable energy devices in various parts of the country, and energy planning. He has experience in the design of sub-systems of gasifier hased technology for decentralized power generation and thermal applications. He was involved in the installation of various Renewahle energy systems in various parts of the country (India); gasifier based power generating systems for village electrification in Karnataka; thermal systems in the industries in silk reeling and

J dyeing in the state of Kamataka, Andhra Pradesh, and Tamil Nadu; Solar home systems, Solar street lights, Solar pumping systems and small sized biogas plants in Haryana. He has a record of

supervising the operation of the gasifier based power generation unit (low capacity) for over 5,000 hour ill the field and over 30,000 hour for gasifier based thermal applications in silk industry. His conceptualizing of estahlishing a supply mechanism has ensured the marketing of gasifier systems in silk dyeing sector and their sustained OIJerati(JIl. He has published about 24 papers in natiollal and international journals, workshops, and conferences and edited a book titled "Biomass Energy Systems ". Mr Srinivas is a Mechanical Engineer with Bachelor's degree from the Kamataka Regional Engineering College, Surathkal. He is currently a Research Associate ar Tata Energy Research Institute (TERl) and is involved ill several ongoing projects in biomass assessment, monitoring of implementation of biomass devices (Biogas plants and Improved Cookstoves) in Southern India, policy research on promotion alld adoption of cleaner technologies and fuels hy low-capacity end-users: Biomass based small and rural industries (Karnataka state), designing and coordinating entrepreneurship development programmes in the area of renewable energy as project leader leading a group of about eight interdisciplinary professionals. Before joining TERI, he worked as Project Engineer at Combustion, Gasification and Propulsion Laboratory, Indian Institute of Science, Bangalore on a project demonstrating the decentralized power generation through gasification technology and also worked as a lecturer for a very brief period at Bapuji Institute of Engineering & Technology, Karnataka. He is the recipient of first prize for presenting a paper given by Ministry of Non-conventional Energy Sources during the year 1993. He is also one of the team member involved in the development of gasifier based cocoon cooking system that was awarded "Energy Globe 200 I - The World A ward for Sustainable Energy, Best 50 " instituted by Government of Austria.

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