Gharats of Uttaranchal: Harnessing Natural Energy
By Manikant Shah
Anyone living in the hills of the state of Uttaranchal in India would know
what a gharat is. The somewhat subdued rolling sound of a continuous
friction between heavy stones near the river betrays the presence of a gharat
nearby. These gharats have a momentous role in utilization of mechanical
power from water streams mainly for grinding purpose.
Man has always tried to develop technology that converts energy from a natural
resource into an energy he can harness to his advantage. As elsewhere, the
people inhabiting the mountainous tracts of Uttaranchal too apparently found
themselves constrained by the harsh physical conditions of the region. Yet
the environment did not cow them down. They neither relapsed into inactivity
and contentment with destiny nor they chose to frantically employ their energies
to overpower and exploit the nature. Rather, they found ways to harness the
flowing energy of the natural resources to their advantage. Apart from other
natural features, the Himalayan regions are well known for their gushing rivers
and streams directly fed by the snowy Himalayan Mountains. Besides the melting
snows of the Himalayas, there are numerous other rain-fed tributaries that
sustain and enhance the water flow in the rivers. In fact, the upper reaches
of Uttaranchal are known as the water-repository of India. People in the past
realized the natural potential of these gushing waters as an unceasing energy
resource and utilized its potential in very many ways. One of the remarkable
ways in which they utilized the natural resource was by way of the gharats.
Constructions similar to gharats and working on a similar principle
are known in the west as watermills.
Generally it is believed that the gharats originated somewhere in
the Northeast region around the 7th century. But there is no consensus over
the date. Currently gharats are in wide use in the whole of the Himalayan
range and the Northeast. The populations of the Himalayas, from Afghanistan
to Myanmar, still live predominantly in agricultural economies, often at subsistence
level. The need for milling is reasonably well served by traditional watermills
spread throughout the region. According to some estimates there are over 500,000
watermills in this entire region.
We made a detailed study of this traditional technology: how it could bee
upgraded to fit in with the modern times and requirements, as also for the
benefit of the poor people of the Himalayan region. We will therefore have
to go into a bit of technical detail.
It is interesting to study the ingenious mechanism of these gharats.
There are three distinct types of water mills. The simplest and probably the
earliest was a vertical wheel with paddles on which the force of the stream
acted. Next was the horizontal wheel, with a vertical shaft attached directly
to the wheel used for driving a millstone. Third was the geared mill, driven
by a vertical waterwheel with a horizontal shaft. This required more knowledge
and engineering skill than the first two, but it shows greater potential. Vertical
waterwheels are also distinguished by the location of water contact with the
wheel, as the undershot wheel, the breast wheel, the overshot wheel and the
Baker wheel. These waterwheels generally use the energy of moving streams. Each
type of mill has its particular advantages and disadvantages. Relatively little
is known of their development before the Middle Ages.
The Report on the Industrial Survey of the Garhwal district of the United
Provinces and the Report on the Industrial Survey of the Almora district
of the United Provinces compiled by H.N. Sapru in 1924 and 1925 respectively,
as part of the general scheme of the Industrial survey of the whole province
under the British regime, gives due importance to these watermills. The reports
point out that there were as many as 5,000 watermills in district Almora and
2,956 watermills in the Garhwal district at the time of the compilation of the
reports. However, the actual number of these mills in the hills even in those
times must have been much more for all may not have been reported for the obvious
difficulty of surveying remote areas in those days, a fact which Mr. Sapru himself
conceded. In these reports a large portion of Uttaranchal hills known then as
the Tehri State were not included.
The traditional Himalayan water mill or the gharat is of the vertical
shaft type. The gharats in Uttaranchal can be found alongside the rivers.
To run these mills a channel is dug along the river to carry the water up to
the mill-house. The gradient of the channel for the flow of the diverted water
is less than the gradient of the river. With this, after several hundred meters
from the diversion, a fall of 2 to 6 meters is achieved for the water. In this
manner water from the stream is tapped and routed through the chute, which then
falls on the flat blades. The water chute consists of an open channel either
made from wooden planks or carved from a large tree trunk. The chute is narrowed
down towards the lower end forming a nozzle. The force of the water let through
the chute with a head of 2 to 6 meters strikes the blades and rotates the wheel,
which in turn, rotates the metal shaft. The head of the water varies from place
to place depending upon the availability of the fall.
The wooden blades are fitted to a thick vertical wooden shaft, tapering at
both ends. Two round millstones, hewn locally, are fitted at the top of the
shaft to act as the grinding mill. The wooden shaft of the turbine is supported
on a stone pivot through a steel pin and held in the sliding bearing at the
top. The sliding bearing is a wooden bush fixed in the lower stationary grinding
stone. The top-grinding wheel rests on the lower stone and is rotated by the
turbine shaft through a straight slot coupling. The gap between the stone is
adjusted by lifting the upper stone with the help of a mechanical lever. The
blades vary in number in different gharats from 11 to 21, which is fixed
lengthwise at the axis to transmit the entire load to an iron base. At opposite
end from the cylindrical axis, a long shaft connects it to the upper part of
the grinder stone. It is interesting to note that the fitness and quality of
grain can be determined even in this nature-run process for which a groove is
made into the upper grinder to set a tapered iron piece that holds the shaft
and grinder simultaneously. An iron base bears the load of the system that in
turn diffuses it over the horizontally laid plank. One end of the plank is attached
to an adjusting lever, which moves upward and downward. The lever governs the
distance between the moving and the stationary part of the grinder. An upward
movement of the lever allows for coarse grinding while the downward is for fine
grinding. Traditionally, channels divert the water from stream/ river to the
mill. A device is also incorporated in the channel to divert the water if the
water mill is not in operation. This device redirects water. It's a simple but
an ingenious construction and can be maintained with simple understanding of
the principles involved.
The components of a gharat may be listed as follows:
1. Flume or chute: A wooden drain kind of thing that routes and rushes the
water from the diverted channel to the rotor blades attached to the vertical
shaft.
2. Grain Feeder: A bag or funnel, which feeds grains to the grinding millstones.
3. Bearing: That helps the upper grinding stone to rotate freely.
4. Upper Grinding or milling stones: The circular Upper grinding stone of
the mill that is directly attached to the shaft and rotates with it.
5. Lower Grinding or milling stones: The circular lower grinding mill stone
through the middle of which the shaft rod passes to support the upper grinding
stone. This lower grinding stone remains stationary.
6. Bush: A round wooden or a leather piece fitted to the hole in the lower
grinding stone through which the shaft rod passes.
7. The vertical shaft: The wooden or iron rod that connects the rotating fan
down below with the upper grinding stone.
8. Runner with hub: The thick wooden portion to which the fans are fitted
and which determines the speed of the rotation of the shaft.
9. Lifting mechanism lever: A wooden mechanism that determines the coarseness
or the fineness of the grains being ground.
10. Bearing: The point at which the pin of the shaft rests giving free rotation.
These gharats are constructed from locally available material such as
wood, stones, bamboo, and reeds. Apart from the technological aspect. these
gharats also have an important sociological dimension. Socially, they
have been the meeting points for villagers to get together. The widespread use
of gharats and its popularity owe much to its simple and cost effective
mechanism. It is important to note the advantages inherent in the indigenous
watermill technology, in particular:
- Simple technology
- Locally designed and built
- Involving mainly local materials
- Low capital cost
- Almost no running costs
- Easily managed and maintained
- Better taste of the ground material
Improvements to the gharats and Power Generation
Grain-milling is the most widespread use of hydro-power in the Himalayas. Traditional
wooden watermills (gharats) have been used for centuries. However in
recent years, gharats have started to fall into disuse due to various
contributory factors. The State, especially the British, other than collecting
water tax from the gharat by and large ignored them. The importance of
gharats was further overshadowed by the introduction of the diesel and
electric powered mills and the inclination of the people towards the speed grinding
machines. The owners of these gharats were forced to descend to the plains
to seek more lucrative employment. Another factor has been the major deforestation
of the hilly regions that has caused the resulted in water supplies to diminish
or disappear altogether.
The design of traditional water mills is centuries old. Because of having extremely
low output these mills do not provide enough profit to the mill owners. Increasing
the output of these mills by developing efficient mill design would undoubtedly
bring significant increase and end use applications. This feeling has encouraged
the technologists to improve the existing design of the gharat. There
are potentially two kinds of improvement that can be worked upon the gharats.
The first involves whereby the efficiency of the present gharats can
be improved. The second, which is more important in the present times, is whereby
power may be generated from these gharats.
The estimates of the number of gharats in the Indian Himalayan region
(IMR), which stretches from Kashmir to Arunchal Pradesh, vary from 100,000 to
200,000 but their number in Uttaranchal can be estimated with more precision.
There could be as many as 60,000 gharats in Uttaranchal according to
the study of HESCO.
Gharats cost the owner anything between 5000- 7000 rupees, and have
to be replaced every 2- 3 years. These gharats have efficiencies ranging
from 10%- 15% only. This indigenous technology is built and maintained by the
miller himself using local materials but is limited to outputs in the range
5-10 kg of flour per hour. If this abundant and renewable waterpower resource
could be exploited more effectively with appropriate and modernized equipment,
it could play a key role in driving sustainable economic development in the
hilly regions. This is a task, which the India Hilly Hydro Project is endeavoring
to address. It is pointed out that with a little technical enrichment input
the efficiency of these mills can be increased by 30 to 40%. The UNDP-GEF Hilly
Hydro Project is an ongoing initiative supported by the World Bank Global
Environment Facility and the Government of India to demonstrate and promote
the use of small-scale hydropower in the 13 Himalayan states of India. The Himalayan
Environmental Studies and Conservation Organisation (HESCO), an Indian NGO based
in Chamoli District, has also been working towards the improvement of the gharats
in the Uttaranchal region.
The gharat upgrade involves replacing the wooden runner with a steel
casting and ball bearing. To gain another 30% of power, the open chute can be
replaced with a PVC pipe and spear valve. The net result is to supply around
1kW of shaft power to the millstones. The new machine costs just the same and
has an extended life span of 30% of the old machines. Additionally, the owner
is saved the trouble of replacing the machine every 2 to 3 years. What is equally
important is that these new machines can be serviced and repaired locally, in
case the need arises. Maintenance procedures are simple and are carried out
with locally available resources and expertise. The traditional wooden runner
is less than 20% efficient. The design objective was to develop a runner, which
can exceed 50% efficiency, but also have a geometry suitable either for casting,
or low-cost welded fabrication. Furthermore, this design of runner is suitable
for converting to a horizontal axis layout at a later date. The new runner is
an outward flow design the water strikes the inside edge of the blades
and escapes tangentially. The new runner is smaller and faster running than
the traditional gharat, with speeds in the range 200-250 rpm.
The Himalayan Environmental Studies and Conservation Organisation (HESCO),
an Indian NGO based in Chamoli District, UP, was responsible for setting up
the Gharat Owners' Association in Chamoli and has been working with them to
design and implement simple upgrades for traditional gharats. The improvements
have involved lining the open chute with galvanised steel sheet, using a Teflon
bush for the top-bearing (at the centre of the bed-stone), and using a fabricated
ball-bearing assembly as the footstep bearing at the base of the rotor. About
12 gharats have been upgraded to date in Chamoli District. The component
and material costs are about Rs. 1500/- and the miller himself undertakes the
upgrade work. Increased output of 2-3 times has been experienced, with stone
speed increasing typically from 70 to 120 rpm. With this upgrade the millers
can grind at least 15kg of wheat per hour. They traditionally keep 5% of the
flour as payment-in-kind, which can be sold for 5Rs/kg (or more). Equating income
against energy use leads to a value for the energy of 3.75Rs/kWh. This is 2-3
times the income that could be earned using the same power to generate electricity,
but at a fraction of the investment cost.
Although the old millstones can be used, it is important that they are 'dressed'
by cutting a pattern of grooves in both stones. This allows the stones to mill
efficiently using the greater power provided by the new runner, otherwise they
may get hot and damage the flour, or even break.
Improving traditional watermills would benefit:
- Millers and their families whose economic situation will be improved by
greater productivity and income-generation.
- Local communities who would stand to benefit from faster and more efficient
agro-processing services, a wider range of mechanized crop-processing machinery,
plus electrical services via an add-on generator, such as evening lighting,
or water-heating, battery-charging, crop-drying, or irrigation pumping at
night.
- Women, who will have a reduced burden of either manual crop-processing,
or of hours or days of walking to electric or diesel machines.
- Manufacturers, who will have the possibility of producing and selling large
batches of simple, standardized equipment.
- Local workshops, which will be needed to supply components and spares, or
provide repair services, or which may choose to develop/copy their own watermill
upgrade.
- The environment, by displacing harmful emissions and reducing the reliance
on wood-fuel
The improved gharat costs about Rs.15,000 (~$300) for all components,
including some civil works. The jet of water can be provided either by the traditional
wooden chute, or by a PVC pipe with a nozzle. The chute is less efficient, so
needs more water to get the same output. If the old wooden chute is used, the
cost for only replacing the runner is around Rs. 6000 (~$130). These modifications
increase the grinding rate to between 15 and 30 kg per hour.
Energy consumption and its availability play a vital role in the development
of an area. Average energy availability and consumption of an urban dweller
is more than hundred times than that of a villager living in rural remote areas.
So a major part of the energy requirements by way of power in the hills of Uttaranchal
can be met by the modification of the gharats. Modern dams use similar
technology except that the stored water is funneled through channels or pipes
that push this high-pressure water through the blades of a turbine. This turbine
generates electricity.
As pointed out earlier there are approximately 60,000 gharats, each
producing on the average about 1.5 KW power, which can be increased up to 5
KW per gharat by a little extra technical input. Due to the increased
efficiency levels of these new machines, they can be effectively employed to
produce electricity in addition to meeting the mechanical power needs of the
people. One of these cross-flow water mills could produce anywhere between 3-
5 KW of power, sufficient to meet the electricity needs of 25- 50 households.
However, the cost of mills and accompanying machinery to produce power could
be around Rupees 150,000. The social and economic benefits arising from having
electricity in these villages would be self-evident: ¾ higher income
levels, more time for recreation and study, and ability to undertake additional
economic activities.
Researchers at the Tata Energy Research Institute (TERI), Alternate Hydro Energy
Centre, University of Roorkee and IT Power Limited, United Kingdom too have
jointly developed a novel technique of increasing the efficiencies of these
mills, sometimes by up to 1500%. It's not the speed of the water that's important;
it's the volume, force and drop (the higher the drop and more volume, the more
force). There are two main categories of hydroelectric power generation: conventional
methods, which produce electricity via water flow in one direction (and are
therefore dependent on seasonal runoff), and pumped storage methods, which are
both producers and consumers of electricity as the water used to generate electricity
can be recycled by pumping it back uphill. A water turbine uses the potential
energy resulting from the difference in elevation between an upstream water
reservoir and the turbine-exit water level (the tailrace) to convert this so-called
head into work. Water turbines are the modern successors of simple waterwheels,
which date back about 2,000 years. Today, the primary use of water turbines
is for electric power generation. The new system replaces the wooden waterwheel
with a cast steel runner mounted on a steel shaft. The new runner fits under
the existing mill-house and can use the same millstones. The shaft is mounted
on a ball bearing at the bottom and runs in a wooden bearing inserted into the
bottom millstone.
Technological up gradation through intervention by voluntary sector has improved
the functional efficiency of the watermills and also made it possible to generate
power. A few of these upgraded watermills have been field tested and propagated
by HESCO in a few Himalayan regions.
Nepal is the only country where significant progress has been made to upgrade
watermill designs, where development occurred in 2 phases. Initially a packaged
steel assembly was developed by a local workshop, which incorporated a vertical-axis
impulse turbine made with fabricated steel buckets and a penstock pipe. There
has been more than one attempt in India to copy and disseminate the Nepali design
of watermill upgrade but these initiatives have failed to make a significant
impact, through either institutional reasons (highly subsidized; no training
or technical support; owners not helped to develop their businesses), or technical
reasons (designs were copied; not understood and transferred; so systems were
inappropriately specified and installed).
Two types of conventional hydroelectric facilities are dams and run-of-river.
Dams raise the water level of a stream or river to an elevation necessary to
create a sufficient elevation difference (water pressure, or head). Run-of-river,
or water diversion, facilities typically divert water from its natural channel
to run it through a turbine, and then usually return the water to the channel
downstream of the turbine.
We have to emphasise the tremendous value of such improvements in the traditional
technologies. Gharat can lead to potential power generation of 2500 MW/hr
or 40 million units of electricity and a cash generation of Rs. 1200 million
per hour.
To sum, it's a source of energy that is eco-friendly and needs to be patronized
and technologically up-graded. Regretfully, this ancient device to utilize the
natural energy, locally known as gharat, has largely remained neglected.
Considering the power scene nationally, let us have a look at the following
figures.
- India's total power generation capacity from water sources 95,000 MW
- Tapped potential 22%
- Potential across Northern Mountain ranges 65,000 MW
- National requirement by 2000AD 125,000 MW
- Current power generated 78,000 MW
The technology for village-scale hydropower is generally under-researched and
could benefit from R&D in a number of fields, for example:
- Hydraulic testing of alternative runner designs
- Hydraulic testing of open chutes relative to penstocks
- Design of low-cost nozzle valve or simple spear valve.
- Design and test a simple mechanical over speed trip.
- Design and testing simple mechanical governor.
- Design and testing robust generator.
- Design and testing improved footstep bearing and adjustable top bearing
for gharat upgrades.
It is highly relevant and the need of the hour to formulate an independent
water policy for the Himalayas. This could encompass technological up-gradation
of water-millers, decentralization of technology and technical institutions,
renovation of existing micro hydel projects and abolition of taxes on water-millers.
The nodal agencies that need to come on a single platform are the Ministries/Deptts.
of RA&E, Energy, MNES, labour, Water Resources, HRD, Forest and Environment
and DST.
Conclusions
Our extensive explorations, though done only as a pilot study, have proved
beyond doubt the potential of Uttaranchal for studying the Traditional Knowledge
Systems. The study of these folk technologies and belief systems is not just
an esoteric study but has also direct relevance to the socio-economic and environmental
problems of Uttaranchal, as also of the world at large.
Our studies have also shown that, in contrast to the received wisdom that the
Central Himalayas were an isolated region, cul de sacs, and had hardly
any role to play in the historical processes of the Ganga Valley urbanisation,
the Central Himalayas played a significant role in such processes. We found
that the early dates of copper and iron technologies make it distinctly clear
that the Copper Hoard Culture of the Ganga Valley had its typological affiliates
in Pithoragarh District. With huge dumps of iron slag all over the area clearly
suggests that it must have been supplied to the plains of the Ganga Valley.
Thus to unravel the early urbanisation processes of the Ganga valley one has
to take into account the archaeology of Uttaranchal also.
Not only the traditional copper and iron technologies are important archaeologically,
but they may provide a solution to the endemic poverty of the region where majority
of males have to leave their homes and hearths in search of jobs in the plains.
Even today more than a thousand families are practicing copper smithy but hardly
have good quality raw material. Copper production was stopped by the British
way back in the nineteen thirties. The area is amply bestowed with copper and
iron minerals of a high grade. The Lohaghat area was producing stainless steel
utensils even fifty years back. These smallscale industries could be revived
for the benefit of the local people, without disturbing the environment.
As we discussed above, the evidence from South China and Southeast Asia indicates
that the early rice technology travelled with the Mon Khmer speaking people.
We know that the local dialects of Uttaranchal have a distinct residue of Mon
Khmer words. Only with rice sowing are associated elaborate rituals which again
indicates its antiquity. If further work indicates that the early rice technology
too travelled from Uttaranchal to the plains of the Ganga Valley, we wont be
surprised.
The Himalayan Medicine System is a gold mine of medicinal knowledge. More
than 800 plants of potent herbal medicines are found here. Instead of the
Multinational companies exploiting our herbal wealth, we should allow the
local people to collect, sell and grow such herbs as part of their employment
schemes. In fact, as part of our continuing studies we are finding that the
HMT was the real knowledge substrate for our Ayurvedic pharmacopoeia.
Traditionally watermills were run using stream water which was free. Of late
though electricity is in short supply, these watermills are going out of fashion.
We have suggested above that by a bit of up-gradation such watermills or gharats
not only could solve the problem of grinding grains and spices but also of power
shortage by modifying them to produce electricity.
Precious art and skills of woodcarving are similarly vanishing fast. They also
provide a source of livelihood and satisfaction too to the craftsmen if they
could be exported to the towns of the hills, plains, and even globally.
To sum, Uttaranchal provides excellent opportunities not only for studying
Traditional Knowledge Systems but also the means to use traditional technologies,
which are sustainable and eco-friendly, for the uplift of the poor hilly people.
References
Sapru H.N. 1924. Report on the Industrial Survey of the Garhwal District
of the United Provinces. Government Press, U.P. Allahabad.
Sapru H.N. 1925. Report on the Industrial Survey of the Almora District
of the United Provinces. Government Press, U.P. Allahabad.
Stowell V.A. 1922. A Manual of the Land Tenures of the Kumaun Division (Hill
Tracts). Government Press, U.P. Allahabad.
REPORTS of the Alternate Hydro Energy Center, University of Roorkee, Roorkee
Uttaranchal, India.
Internet reports of HESCO.
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