CHAPTER I1

A CRITIQUE ON MAJOR SOURCES OF POWER GENERATION

Power sector is a core component of infrastructure and has an important

bearing on economic growth. Main sources of power generation are major

hydropower and thermal power. Nuclear power, renewable sources of power

consisting mainly solar power, wind power, biomass and small hydro power are

other available potential sources. The chapter is a critical study on these sources of

power generation. It is divided into four sections .Many criticisms are existing

against major sources of generation-Thermal and Large hydro. The potential threats

of these sources that made thermal power and mega hydro power projects

unattractive options today are discussed in detail under sections I and I1

respectively. Selected cases from the kerala power system are taken as examples.

Section-111 deals with the nuclear power projects. Renewable sources of power

generation, their constraints and the prominence of small hydro power over other

renewable sources are discussed in section IV .

2.1.Progress And Trends In Power Generation In India

Last fifty six years showed phenomenal progress in power generation,

thanks to the advent of Five year plans. Installed capacity has increased from

1362 MW in 1947 to 1,07,913 MW in 2003. Though tremendous progress is

made in generation (power supply) it has always been far short of demand. Oil

crisis in 1972-73 and 1978-79 has pulled down the growth rates to a new low

and never again did it fully overcome that shock. In India coal based thermal

and major hydroelectric power have been the mainstay of the power system

though thermal generation occupies the most predominant role.Table2(1) shows

the progress in capacity addition in the three major sources of power generation

in India.

Table Z(1)Progress in power generation of major sources-India

Source:compiledjrom iheCMIE statistics , Ministry ofpower

Note: All capacities in MW;

2.2. Major Means Of Electricity Generation :A Critique Of Thermal And Mega Hydro Power Projects

'The major means of electricity generation in India are coal based thermal

power and hydro power. States with abundant water potential like Jammu and

Kashmir, Kerala, Kamataka and Meghalaya depend mainly on hydro electric power

while states with enormous coal reserves like West Bengal, Bihar and Delhi depend

mainly on coal based thermal power. Andhra Pradesh, Madhya Pradesh, Uttar

Pradesh, Tamilnadu, Orissa, Rajasthan, Punjab and Haryana make use of both the

resources evenly. These energy resources are beset with various problems. In the

new millennium, where sustainable energy development is a major concern of

power sector the problems faced by these resources should be examined thoroughly.

First, let us take the case of thermal power generation.

Section 1

THERMAL POWER

Thermal power generation has been and will be the bedrock of India's

power sector. It accounts for nearly 70% of power generated in the country. Coal,

Oil and Natural Gas are the major fuels used in Thermal Power Generation. Coal

is the most widely used fuel, given the large reserves India has; but Indian Coal is

predominantly of inferior quality with relatively low gross calorific value.

Excessive use of this form of energy resource will result in environmental

degradation and high auxiliary consumption.

(a) Small particles from combustion eventually reach the ground,

threatening human health and property.

(b) Disposal of the ash that is produced as a bi-product of consumption requires

large amounts of land; leaching ash can contaminate ground water.

(c) Carbon dioxide released from fuel by combustion contributes to global

warming and climate change.

(d) Power stations require large environmentally valuable land areas

(e) Large thermal projects confront resettlement and rehabilitation issues

(f) Acid gases that are produced when fossil fuels are burnt are eventually

precipitated in acid rain.

Relevant problems contributing to inefficiency of thermal power projects:

Apart from environmental impacts, there are certain other factors which

go against Indian TPP. Majority of TPPs are managed by SEBs and public

sector units. They are relatively inefficient due to a)inadequate financial

resources, b) poor capacity utilisation c) slow project implementation-time and

cost over runs d)management inefficiencies-overstaffing e)cumbersome

bureaucratic procedures and f ) poor and inadequate response to protect

consumer interest and lack of autonomy.

A low Plant Load Factor(PLF) is a major problem faced by TPPs. PLF

which stood at 52.5% in 1974-75, climbed to 61% in 1993-94, but declined to 60%

in 94-95. The low PLF is a worrisome factor because even a 1% improvement in

average PLF can generate an extra 500 MW of power. Auxiliary consumption of

thermal plants is also very high(lO%). These factors make TPPs inefficient.

Economic aspects

The Electricity generated from thermal power plants is considered to be

very costly. The uneven distribution of coal and oil reserves result in the very high

transportation cost of fuels and resultant hike in the price of thermal power. The

cost of thermal power is normally around Rs.41unit. Thermal power suffers cost

escalation also. Since price of hels always shows an increasing graph, the cost of

thermal power also increases over time.

In regions lacking oil or coal reserves, installation of thermal stations is

uneconomical. Kcrala is a good example of this. Let's take here the cases of

thermal power stations established in Kerala to understand the problems TPPs

create in a state with no foundation for its development. Brahmapuram Diesel

power project (106 MW) and Kozhikode Diesel power project (128MW) are

KSEB owned TPPs. IPP thermals NTPC Kayamkulam (350 MW), BSES

Kochi(157 MW) and RPG, Kasargode(20MW) are the existing schemes. The

KSEB thermal plants are almost idle. Let us take the case of NTPC, Kayamkulam

and BSES. Kochi here:

Kayamkulam thermal power project(350 MW-NTPC)

The project was established by NTPC with a project cost over Rs.1300

crore. NTPC has been appreciated for completing the project in a lesser time than

stipulated. Even in the beginning of working of plant, the cost of generation was

Rs.4 per unit which was difficult for the Board to afford; the costs escalated along

with the spiralling prices of Naphtha(the fuel used in Kayamkulam plant). At the

time of agreement. the price of Naphtha was Rs.6000 per tonne. Now, its price is

hovering around $285 a tonne in international market(1999 prices). The effective

price in India, inclusive of customs and excise duties is about Rs.13,000 a tonne.

The escalation in fuel prices has resulted in increase in unit cost and selling

cost. In July 2001. the rates at which NTPC sold power to the Board was

Rs.4.lOlunit; in 2002, it was above Rs.S/unit. In the end of 2002, rate is around

Rs.4 due to a slight decrease in the Naphtha prices. Of this Rs.l.101- is fixed cost

and the rest is variable cost. According to the agreement between NTPC and

KSEB, the entire 350MW is to be supplied solely to the KSEB and KSEB has to

pay a fixed cost of Rs.l.lO /unit even if it does not buy the electricity generated,

with no fault of NTPC. The latter clause is termed 'deemed generation' which is a

major trap in the agreements with all the IPP thermals. KSEB is suffering heavy

losses on this account.

In the case of Kayamkulam, unit costs are calculated on the basis of

expenditure of the project, providing NTPC 16% profit on total expenditure.

Buying costly thermal power was posing a heavy burden of Rs. 540 crore yearly to

the KSEB. So it started buying lesser units of electricity from the plant, but have to

pay fixed prices for the units it does not even buy. KSEB's dues to NTPC stand at

Rs.956.90 crore in Jan 2002; the dues increases year after year. In addition, KSEB

owed NTPC Rs: 170 crore towards interest on bonds issued earlier.Now, in order to

tide over the crisis, the Govt started selling Kayamkulam power at competitive

prices to the neighbouring states. On May 16' 2002 the Govt. decided to give

180MW to the central pool.

BSES Kochi (157 MW)

The Power Purchase Agreement(PPA) between BKPL(BSES Kerala Power

Ltd.) and KSEB for combined cycle project was signed on May 3rd,1999. The project

cost was Rs:572 crore. According to the agreement, the Board will buy 80% of power

generated (30 lakh unit); The cash has to be deposited in the bank on a prepaid basis.

BSES is buying Naphtha from Indian Oil Corporation(1OC). It requires fuel,

costing Rs. I .5 crore daily. Due to pending bills with IOC with respect to fuel

supply, the plant was shutdown in sept.2001,but restarted generation in the

emergency situation of shutting down of Brahmapuram. But, as the dues of KSEB

to the plant reached Rs.120 crore, BSES has stopped generation in October 2001.

I t restarted generation on April 2002 considering heavy demand. Even now, it is not

sure for how long the production from the plant will continue. So the reliability of

power supply from the above mentioned thermal plants is questionable.

The thermal projects of the state which shares 6% of electricity generated in the

state requires 15% of total production cost. Kayamkulam plant, which shares 16% of

electricity generated, requires 48% of total production cost. But hydro projects which

produces majority of electricity produced here, have only 7% of total cost.

Central power Ministry has recognised the limit of buying private TPPs

power as 68.5%; but Kerala is buying 80%-100% of power generated from these

stations. TPPs thus pose heavy burden to Kerala. Now, lets go over to the next

major sources of power generation-HYDRO POWER especially major hydro

power. Southern states like Kerala have abundant HP potential and major HP sites.

Section-11.

HYDRO POWER-MAJOR HYDRO POWER SCHEMES

India is a veritable fountain head of hydro power, though only around 25%

of the potential is utilised for electricity generation. Central Electrical Authority

(CEA) has assessed India's hydro potential as 84,000MW at 60% load factor or

1,35,00OMW at 40% load factor, which is equivalent to 600bn units of firm energy

annually, while the installed capacity of hydro was 26910 MW in March 2003.

Thus nearly 75% of country's hydro potential remains unexploited.

Types of Hydro-Electric Schemes:

1 . Run- of -river without pondage(litt1e or no storage)

2. Run-of -river with pondage(with storage capacity suitable for diurinal

variation in power generation)

3. Sstorage schemes(with reservoirs to store excess water in wet months)

4. Pump-storage schemes(with two reservoirs 'upper ' and 'lower', water

flows from the upper reservoir to the lower reservoir during generation

and from lower to upper reservoir during pumping)

The large storage schemes are commonly described as the major hydro projects

while the run-of-river schemes are mostly small hydro power schemes (SHP).

Criticisms

Despite all the advantages attached to it, major hydropower schemes have been

criticised for the high initial investment, longer gestation period and the construction of

large dams causing huge submergence and displacement of local population. Gestation

aspects of mega hydro projects resulted in time and cost over runs.

1I.A.Gestation Aspects

A common allegation against hydro projects is the longer gestation period

involved. Considerable time is taken for the investigation of the project itself.

Land acquisition for the project also consumes a lot of time. Land being a state

subject poses many problems for acquisition before the start of the work due to

involvement of multifaceted agencies like state departments, district authorities,

defence and forest authorities. It takes anywhere between 2 to 5 years to obtain

forest and environment clearance at present. Techno-economic clearance usually

takes 4-6 months. After techno- economic clearance a hydro project has to go

through a series of statutory clearances which are quite time consuming and again

on top of it, has to pass through a long bureaucratic channel before any investment

sanction is accorded. In order to save some valuable time of project cycle, the

Govt. has recently accepted two-stage clearance of HP in the central sector, but is

not yielding results as envisaged due to many valid reasons.

Inter state disputes over distribution of rivers, Investment shortages, Forest

Act 1981 which was strict on forest and environmental clearance of projects,

inordinate delay in getting sanctions for the projects submitted to CEA, labour

problems, contractual failures, scarcity of raw materials and corrupted nexus

between contractors, officials and labour unions have contributed to gestation lag

of projects.

In Kerala. where hydro electric projects are the thrust of electricity

generation, many hydro projects suffered lag in gestation. It incurs heavy losses to

the Board on two grounds- the revenue earning that can be accrued if projects were

completed in time, and the interest on the invested capital. Industrial growth that

would have occurred by utilising power from these plants, and the resultant

employment opportunities are lost due to the gestation lag in hydro power projects.

Average delay of project is a stupendous 160%. Little attention is paid to the

serious economic costs incurred by the phenomenal delays in the execution of the

projects.

Gestation factor of HPs: A case of Kerala HPs.

No mega hydro power projects in Kerala is completed in time except the

Sabarigiri project. Time over run has resulted in exorbitant cost over run. Cost

escalation of some of the lagged projects are shown below.

TableZ(2):Cost escalation in mega projects-Kerala

I I t k k i Stage 1 9 7 5 1 I987 I 410 1 1459 1 255 I

Name of Projects

ldamalayar

Year of Starting

1970

ldukki Stage I1

Almost all the projects have taken more than 12 years for completion.

Kakkad the most infamous mega HP project of Kerala has taken 23 years to

complete. Let's take its case here.

Sabararig~r~ augmentallon

Kakkad

Kallada

Lower Per~yar

Kakkad HEP:- When the work of Kakkad project began in 1978, the estimated

cost of the project was Rs:18 crore. Since the capacity was only 50 MW, the

project should have been completed in 5 years; but the project took 23 years for

completion. When it was at last commissioned in 1999, KSEB had spend nearly

eight times the original estimate. This has changed the attitude of the govenunent

and the KSEB towards major hydro projects.

Year of Commission- ing

1987

1980

An unprecedented situation of seeking approval of Ministry of Environment

for a second time has also arised. At the time of commissioning of the project

Source comp~led from KSEB statistics; * Actual Estimates.

1976

1976

1981

1983

Original Estimates (Rs.Lakhs)

2340

1986

1999

1994

1997

Revised Estimate (Rs.Lakhs)

9003

I I

% increase over original estimate

-

284

3168

128

1860

1180

8843

6800

996

* 14680

'1365

'3 1000

114

678

690

16

25 1

(1 999 August) leaks were noticed at several points in the tunnel which reduced the

capacity to 43 MW from 50 MW. KSEB had to shell out Rs.15 lakhs for the

repairs. Thus Kakkad is the best example to show how high cost and time escalation

in a project can destroy the credibility of a method of power generation itself.

Another factor which is more serious and more dangerous is the

environmental and ecological threats imposed by large dams of mega HPs. Large

scale environmental problems associate with large HP projects make them

unsustainable sources of power generation.

1I.B. Large Hydro Projects And Their Environmental Threats

Major hydro projects have large dams with very high storage capacity.

Large dams and associated submergence have many negative impacts on the

ecology and environment. Main effects are discussed here:-

a) Submergence: Large scale submergence is the major problem associated with

large hydro projects. Submerged areas can be towns or villages with substantial

population, archaeological sites, religious monuments, cultural sites, rare flora and

fauna and thick forests. Submergence of habitated areas create rehgees and victims

of population displacement. Valuable archaeological remains of second century AD

has been moved out by the reservoir of Nagarjuna Sagar dam. Vast areas of green

forests also are drowned by large projects. Between 1951-76, nearly 479 thousand

hectares of forest were destroyed for construction of various river valley schemes.

Submergence of forest induces soil erosion, water logging, land slides, flash

foods, siltation and sedimentation. According to a UNESCO study, water shed of

one river when forested releases between 1% to 3% of total rain fall; once the trees

were cut down. a phenomenal 97 to 99% ran off. Submergence can range from few

hundred hectares to nearly 80,000 hectares with the average of about 2000 hectares.

Possible extinction of fish species, some aquatic populations, plant and animal

species and water borne diseases and health problems are also threats of

submergence .

Though submergence have so many negative impacts, project economists of

mega projects never include ecological loss in their study . On the contrary timber

recovered from submerged area have been treated as revenue of the project, as trees

are cut before submergence - example is Sardar Sarovar project .

b) Reservoir Induced seismicity: It is apprehended that impounding of massive

waters in storage reservoirs accentuate local mass and the pressure thus may be

enough to initiate seismic activity. Indeed all over the world major earth quakes

have been recorded near large dams, though there is no agreement among experts

that they are dam induced. Gupta and Rastogi, however, point to about thirty such

cases in India, where the initiation or enhancement of seismic activity has been well

evidenced following impounding of reservoirs behind large dams(CSE,1982)

The recent tremors in Kerala had epicentre near the Mullapperiyar dam.

Kerala had experienced nearly 40tremors within a span of 26 days between

December IZth.2000, and January 7th, 2001. Magnitude of tremors ranged

between 3.5 and 5 on the Richter scale. The epicentre of bigger tremors were

within 40 kms of the dam.

c) Reservoir siltation and sedimentation: Reservoirs have a tendency to silt up

much faster than anticipated and in the process it becomes short lived.

Govt. of India's survey has concluded that annual sediment flow is at least

four times as high than that was expected. Silt forms a brick hard pan called 'mud

flat' reducing the storage capacity and effectiveness of hydro projects on flood

control or Irrigation or other purposes. The reservoir when eventually full will be

unusable for agriculture by turning the land a muddy waste land.

d) Floods: Major dams are generally considered as effective for flood control.

Some dams like Idukki(Kera1a) , Hirakkud dam, Damodar valley, Sarovar

dam(Gujarath) and pong dam (Himachal pradesh) were constructed with the main

purpose of flood control; but the results are not encouraging (Bandhyopadhyay,

1985). Dams are supposed to act as buffer between lean and peak flow period in

reservoirs. Heavy sedimentation lowers the flood control capacity of the dam.

Chronic power shortages also place heavy strain on big projects, because

even in rainy season, when the reservoirs should be kept almost empty in order to

collect flood waters, they are kept full for the sake of maximising power

generation.. The pressure of flood waters will then endanger the dam with

possibility of its collapse. To avoid this, vast amounts of water are released.

thereby aggregating the magnitude of floods rather than reducing it. Recently in

Kerala, unexpected release of monsoon water from Moozhiyar dam has resulted in

flash floods in the central Tranvancore regions of the state.

e) Dam failures: Collapse of dams due to construction related or geological

problems is also a question of concern. The International Committee On Large

Dams(lNC0LD) has reported that in the last 175 years, 600 dam failures and

related incidence has been reported world wide ie. about 3 dam failures occur

worldwide every year. Several large dams like Tehri being built in the geologically

delicate North-West Himalayas is a worrisome matter. No specific measures have

so far been taken in this regard. Callous negligence could result in loss of life of

people living in the nearby regions.

f) Water logging: Decomposition of organic materials in the lake bottom is feared

to result in production of methane and hydrogen sulphide. Hydro reservoirs are

also apprehended to cause rise in the nearby water table, water logging and

subsequent salinity leading to oxygen depletion. They are said to be responsible for

evaporation losses and temperature variations causing change in climate. In India,

6mn hectares of land area are affected by water logging, 4.5mn hectares affected by

salinisation and 2.5 mn hectares affected by alkalinisation. In case of Sabarigiri

station(300MW) in Kerala, hydrogen sulphide was found emanating from the

turbine discharge. On investigation, it was found that vegetation was left before

filling the reservoir

g) Health problems: Reservoirs and its submergence have created a breeding

ground for disease vectors like malaria, flurosis and other water-borne diseases.

According to India's sixth plan document,-"studies have shown that construction of

large reservoirs can result in the elevation of sub-soil water in the vicinity with

consequent changes in the levels of fluride, calcium, trace metals etc in soil

sedimentation. This in turn results in emergence of diseases such as flurosis, in

people who are forced to use contaminated water." For instance, the National

Institute in Hyderabad has conclusively revealed the seriousness of flurosis in areas

adjacent to the Nagarjuna Sagar dam.

h) Displacement and resettlement issues: Large dams with huge submergence

result in large scale displacement of people. Cash compensation is not enough to

ensure satisfactory rehabilitation. Back up of village communities with strong

social ties, when villages are resettled in disintegrated way can cause much distress

to the people. The class of 'environmental refugees' created by large scale

displacement of people associated with large dams is the biggest problems

encountered by Mega Hydro Electric Projects.

i) Location bias and Inequality: Large dams mainly benefit people in the plain

and not people living in the hill and mountainous regions. The people living in the

hills and remote regions are not benefitted from these projects since electric supply

does not reach most of the regions. In India 15% of the villages are yet to be

electrified. 85% of population lives in villages in India. Even in electrified villages

electricity does not reach the far flung areas. Mega projects have a bias towards

rich and the affluent class and it does little to alleviate poverty or existing social

inequalities.They largely benefit big contractors, engineers, big construction

companies and economically, politically and socially powerful people, not the poor

masses (Singh, 1999).

Economic cost of large hydro projects are greater than the revenues from them.

The social and environmental costs of large dams have to be paid sooner or later.

In the Kerala context the hydel projects existing or planned are located in

the Western Ghats. The conventional type of energy generation was regarded as

harmless till recently. But they indeed have done damages to the bio-diversity and

environment. An example is Idukki whose establishment led to reduction of 96 rare

species due to human interference and their malpractices. Wild species are valuable

gene donors to improve our food production, develop new medicines and material

requirements in future. "Kerala being situated on the lap of Western Ghats in the

south-west comer of lndia, near the equator, experiences high precipitation of

south-west monsoon and scattered rainfall regimes of north-east monsoon, which

keep the hydrological cycle in full swing for about six to eight months. Such a

humid tropical climate having high rainfall and high humidity serves as a green

house for luxuriant bio-diversity of Kerala. This can be evident by the fact that

though i t occupies a mere 1.18% land area of India, it has 22% of India's bio-

diversity. The recent study revealed that Kerala harbours 10,035 plants and 7,265

animal species in different eco systems such as tropical evergreen and shola

forests, semi evergreen, moist and dry deciduous forests and low and high altitude

grass lands. The Western Ghats of Kerala region is already noted as "hot spot

areas" because of high species diversity and rich endemism. The global scale

adopted for declaring hot spot areas by having 500 species in 100km2,where as in

Kerala ,at any given place in the Western Ghats ,a mere 2km have more than 350

species and you can imagine how luxuriant we are in terms of bio-diversity. Infact

the Western Ghats of Kerala is now referred as the hottest of the hot spotsw' . So, an

establishment of mega hydel power project in these 'hottest of hot spots' is

environmentally disastrous.

It is quite evident from the above facts that the major sources of power

generation -thermal and major hydro -are nonviable and non sustainable.

2.3. NUCLEAR POWER

Another alternative left is nuclear power. India does not have substantial

resources for its installation. The present installed capacity is 2720 MW. The

nuclear power project is also not considered as environment friendly due to the

scope of reactor accidents and radiations. Its installation in densely populated areas

I A study conducted by EIA team of Co~rnbatore based Salim Ali Cenve for Ornithology and Natural History-SACON-The Hlndu. Feb 16 ZOO2

for eg.in states like Kerala is not a rational step. The Indian practice on nuclear

power so far was based on obsolete, dangerous, polluting, costly and uneconomic

technology. The Boiling Water Reactors(BWR) at Tarapur emit far greater radio

activity. The CANDU reactors emit far more radio active hydrogen in the form of

water vapour than BWRs or PWRs(Pressurised Water Reactors). Tritiated water

that possibly enter human body can cause miscarriages or birth defects. In

Kalpakkam Dept of Atomic Energy is to build 500 MW Sodium -cooled Prototype

Fast Breeder Reactor.Unlike water -moderated reactors, sodium - cooled fast

breeder reactor type can explode due to an accidental nuclear criticality.

Worldwide, seven out of the 11 plants built,(sodium -cooled fast breeder reactor

type)have already shut due to concerns regarding accidental explosions. 4

remaining ones are due to be shutdown.

Fuelling fast breed reactor with plutonium require routine operation of a

reprocessing plant that could handle large amount of spent h e l with high

plutonium concentration. Operation of reprocessing plant is costly and

uneconomical .Similar large plants operating only in England and France are

economical and so polluting that several Western European union countries have

called for their closurez.

Cost wise also nuclear projects are unattractive; they are highly capital

intensive. Organisation for Economic Co-operation and Development (OECD)

has estimated the costs of nuclear, coal and gas generated power (including

capita1s)as 4.60 cents per kwh for nuclear power,3.87 cents per kwh for coal

and 4.19 cents per kwh for natural gas3. So nuclear power is much more

expensive than others4. Initial cost of the plants are very high; cost overruns

also play the part in escalating project cost. Opinion of experts and the Indian

experience on nuclear projects suggest that nuclear PP also is not an

economically competitive environment friendly solution given the present

polluting technologies

- - W u n MGjani 2001 Thc Hindu, Apnl25. 1 Urvlivm I n f d o n Cave .hp'l wuw. uie.mm. dInipOR ht

M. V. RMUU, PMEC(ORUS-ThcH~2001 July 16.

Environmental pressures against the rapid use of major sources of

power generation like thermal power, large hydropower and nuclear power has

compelled the power engineers, scientists and the government to divert their

attention to renewable sources of energy development. They are clean

,abundant and environment friendly. They have tremendous scope in the

electrification of remote rural areas too thereby catalysing the development of

these areas.

Section 1V

2.4. RENEWABLE ENERGY SOURCES

Water, wind, biomass and solar are the major renewable energy

resources of India. The MNES has estimated that 126 Giga watts of power

generation capacity is available from renewable energy sources in the long

term.

Table 2(3): Technical Potential for Renewable Energy

Technologies

I Wind 1 2 0 ~ ~ I

Potential

Biomass

Improved wood stoves

Solar energy

Small hvdro

Bioeas ~ l a n t s 1 12 million nos.

17,000 MW

120x10 'nos.

20MWiKm2

10 GW

2.4.1.Biomass and Gasifier Technology

Ocean energy

Wave power

Tidal power

The high rate of photosynthesis from available biomass in India such as crop

residues, the high rainfall and isolation etc makes biomass a prospective resource.

Bagasse-based cogeneration uses a combination of direct combustion and

gasification of biomass to generate energy. The estimated potential for bagasse

50 GW -

20 GW

9 GW Source:compiledfrom MNES Reports

conversion in India is approximately 3500MW. But there are technical challenges

in using these resources effectively since biomass is a complex and variable

material with difficult combustion ;there are also logistical problems in ensuring an

adequate and timely supply of fuel on an year- round basis. In many areas of India,

especially in the southern states like Kerala, Karnataka and Tamilnadu the idea of

biomass collection itself is not popular.

Gasifier technology for decentralised power generation has been developed

and demonstrated in India. The difficulties should not be under estimated. A

gasifier comprises a small chemical plant producing low quality fuel from a low

grade feed stock of variable quality; the fuel is often contaminated ,may be difficult

to bum or may even damage the engine. About 16MW of gasifiers have been

installed in India. In 1993 about 20% of installed gasifiers were surveyed; only 14%

were operating as expected.

2.4.2.Wind power:

Wind power is the most used renewable source of power in India with an

installed capacity of 1736 MW. Wind energy units consist of a combination of

rotating turbines driven round by the wind and a tower which holds the turbine up

in the stream of air. The most common type is a two or three bladed turbine.

Variability of wind limits the wind energy production apart from the

malfunctioning of equipments; system is very inefficient at low wind speed and are

prone to fail if operated in very high wind.

The major constraints in wind power generation include operation problem

in matching supply and demand since wind power varies seasonally. It is location

specific too. The wind power can be developed only in regions with sufficient wind

speeds(>l8km /hour as annual mean wind speed) . In Kerala, Ramakkalmedu in

Idukki is a potential site for wind farm with a wind speed always at 35 km(for

6months from the west and the rest 6months from the east). The total potential is 25

MW capacity(65mu at 30%LF). The project will cost Rs.100 crores. Cost of

generation is assumed to be between Rs. 2.50 and Rs. 2.80 per unit. Kerala has

already established 2 MW capacity wind farm at Kanjikode in Palakkad district;

another 16 sites at idukki, Palakkad and Ponmudi are found out as potential sites. If

used. Rs. 172 crore units can be generated(ANERT,2002).The initial cost of wind

power is as high is Rs. 4.5 crores per MW. Wind power is a renewable source with

the lowest density of generation i.e energy from a specific point is the least. The

heavy variation of wind speeds, resultant non durability ,non reliability, high initial

investment are the major constraints of wind power generation.

2.4.3.Solar energy:

Solar energy has huge potential. Three important types of solar systems exist: a)

ResidentiaVcommerciaI solar heating. b). Solar process heat and thermal electric

generation. c)Photovoltaics. Sunlight is most evenly spread of all renewable sources.

The occurrence of night falls brings down the capacity factor of solar installation below

50% ;in cloudy weather it will be below 20-25%. The figure vary with locations.

Len& of service life is also not quite clear. 10 to 30 years is estimated though not very

definite. It is reliable as down time for equipment repair is very littles.

Cost is the major constraint for photo voltaic system. Solar energy is the

most expensive among all sources of energy and this is its major setback. Initial

cost of solar energy system is very high. It is a low density resource also.

2.4.4.Small hydro power (SHP)

The best-developed form of hydropower is electric generation from falling

water. Rainfall furnished water supply and pull of gravity provide the basic driving

force. Higher the drop of water at a site (head)and larger the quantum of falls,

greater will be the potential energy.

Usual features of SHP are a water diversion structure and a powerhouse.

The dam or diversion structure is used to channel some or all of the river or stream

flow through the power house turbines which run dynamos that generate electricity.

SHPs are generally of two categories: storage scheme, in which a dam creates a

pond upstream either for water storage or to increase the head immediately

available at the site by raising the water level on the upstream. Second is run -of - river scheme with a small diversion structure whose potential rely on steepness of

the site or the velocity of water flow. Technical details are given in the Appendix.

The SHP generator is environment friendly. The equipments, dams and

other structures are extremely reliable and trouble free. Auxiliary consumption is

very low (1%) compared to thermal (10%). Run of river SHPs are seasonal subject

to considerable variation in water flow. Summer droughts, season to season

variation and substantial variation in rainfall year to year make the project operate

at less than full capacity.

In India SHP has an estimated potential that amounts to 10,000MW. Every

time water runs down the hill it is in a sense prospective source of power

generation. So in reality potential may be much more. The Ministry of Non-

conventional Energy Sources has examined 2679 sites that have potential capacities

of up to 3MW each. It estimates that SHP could represent 1% of the likely installed

capacity of India by the year 2015. Since India is bestowed with abundant water

potential, of which nearly 75% remains untapped and since major hydro electric

projects face so much criticisms and protests on environmental grounds, SHP has a

significant role to play in tapping the unutilised water potential of the nation.

The North eastern region, the Southern Indian states especially Kerala and

Karnataka are prospective treasures of SHP. The small hydro schemes are classified

as small, mini and micro schemes: schemes up to 1 MW capacity is considered as

micro hydel schemes, schemes with installed capacities ranging between 1 to 2 MW

is regarded as minl hydel schemes and schemes with capacity less than 25 MW

capacity is considered as small schemes. The mini and micro hydel schemes can be

constructed on streams in hilly areas and canals in plains. Schemes in hilly areas

serve the function of meeting local needs of isolated areas while the schemes in

plains can serve the irrigation or water supply purposes. Storage schemes and run of

the river schemes have their own wider spectrum of purposes.

SHPs are environment friendly, competitive and economic. They are

durableand reliable. They are location specific also. In India schemes of small

hydro power categories have developed from very early times; first micro plant was

at Ilarjeeling in 1880s having a capacity of 200kw. The development grew steadily

over the years. With the alternative of diesel generation that became possible

afterwards, small hydro generation fell into the background. Now a days, with the

cost of fuel going up over the years SHP is receiving impetus. By 1995-96 SHP

stations with a total capacity of 121 MW has been constructed and 234 stations are

under construction. SHP is an attractive and potential renewable source in India.

2.5.Comparison of Small Hydro Power with Other Renewable Technologies

Unlike solar energy, other renewable sowces like small hydro,wind etc are

more location specific. It will be more beneficial to harness these resources from areas

where they are sufficient and abundant in supply. Among the feasible sources, southern

India is more abundant with hydro and wind potential while north India is strong in

bagasse potential. A firm technical basis exists for small hydro and wind power

projects and they appear to be economically attractive for suitable sites. Free and

abundant availability, economic competitiveness and scope for electrification of remote

areas etc make small hydro project the most promising of all renewable energy sowces.

A Study conducted by Environment Resource ~ a n a ~ e m e n t ( ~ ~ ~ ) ~ , India

has assessed the economic viability of Renewable Energy Technologies(RETs)

based on levelised annual costs (LAC)'.

Table:2(4). Levelised Annual Cost (LAC) of Renewable Energy Technologies

Source: Renewable Energy in 1ndia:A Special Study,ERM-India

6 op ct l .tRM.IW7

Levelised Annual Costsl,AC is defined as annualised cost (total of the total capital and operating costs of respective technologies) dlvided by annual net electricity generation (kwh)

I t should be noted that LAC does not allow for the controllability of

energy and thus tends to flatter options such as wind (whose energy availability

depends on weather) compared to co-generation using bagasse. The table shows

that cost of generation of small hydro power at above Rs:1.43/kwh is highly

competitive with conventional technologies, while technologies like SPV and

solar thermal are far less economically viable than other options. The study also

stressed the role of renewable energy sources in electrification of remote rural

areas compared to conventional grid based power which would incur additional

transmission costs. The study calculated the economic costs of renewable energy

supply and grid based energy supply to off-grid locations as presented in the

following table.

( Grid system

Table 2(5)Supply cost of power at a remote location

I Decentralised system: I I

System Cost of supply(Rs:lkwH)

Wind:

Small hydro power:

The Study shows that compared to wind and other decentralised modes of

generation, the small hydro power projects are economically more favourable than

grid supply to meet demand at remote locations.

2.87

1.43

Wood gasificat~on:

Biomass cornbustion(bagasse):

2.12

1.69

Source:-Environmental Resource Management,lndia Study. 1997

The potential sources of electricity generation are discussed in the

chapter. Thermal power, hydro power, nuclear power and renewable sources of

power are the existing main sources of electricity generation in India. Among

them major hydro power and thermal power are the bed rock of Indian power

system ;same is Kerala's case. Both these sources are environment unfriendly.

lnfact they affect environment and ecology in precarious dimensions. These

resources declared as economical by their proponents, if their huge social,

environmental costs are added, will become un economical and non viable. The

high environmental consciousness and strong environmental movements also

restrict the future scope of thermal and large hydro resources. Fluctuations in fuel

cost according to the international market prices, non-availability of adequate fuel

supply. depletion of fuel resources, high plant consumption, low PLF are

additional weaknesses of thermal generation. Long gestation lag in construction

of projects and resultant time and cost overruns are reasons that make large hydro

projects costly and incompetent. Third main source is nuclear power. It also

suffers from environmental threats and is uneconomical.

Given the circumstances, the alternative left is to utilise environment

friendly renewable technologies. Potential of renewable sources- solar, wind,

biomass and small hydro power-is very high. Location specification, cost-

ineffective technology, seasonal nature of resources are the major constraints of

most of the renewable sources.

If location is conducive to its development SHP is a competent, attractive

and environment friendly source of power. Now,let's take the case of power

sector of Kerala and discuss the conditions demanding the immediate

installation of SHP.

THE P8WEB SEETUB BF WRflLfl-RN

UVERVIEW