Case Study 16: Creating synergy between traditional and modern technologies

The Himalayan region has several perennial streams, rivulets, and rivers where water flows down with great speed and force. This region is therefore a great source for generating hydro power. For centuries, the people living in these regions have been using hydropower to run flour mills, also known as gharats. However, since these traditional watermills produce less than 1 kW of mechanical power and are able to grind only 5 to 10 kg of flour/hour, diesel-run flour mills are gaining popularity and are giving tough competition to traditional watermills. These traditional watermills are therefore slowly running out of business. Many such watermills in Uttarakhand are either abandoned or on the verge of closure.

A traditional watermill consists of a grain hopper, mill stones, water chute, and a wooden runner. The grinding capacity of the traditional watermill is 5 to 10 kg of flour/hour with an efficiency of less than 20%. The performance of a watermill depends upon the following points. The force with which water hits the runner

? RPM (revolutions per minute) of the runner and the stone

Stone dressing

? Gap between the bed stone and drive stone

? Weight of the top stone? Feed rate from the hopper

? Based on these parameters, an improved watermill was developed to maximize the grinding capacity of the existing mill stones at an affordable cost, so that the watermills could compete effectively with the diesel mills.

In the upgraded watermill design, the wooden runner is replaced by a smaller size metallic runner, to improve the RPM. The point at which the wooden chute releases the water jet to hit the runner blade is adjusted in such a way that it can hit the water with greater force. Alternatively, a nozzle made of PVC pipe is also introduced. The advantage of the nozzle is that it can generate more force even when the water flow is less. The traditional watermill requires a greater flow of water. Shisham bush and the rynd will maintain an optimum gap between the mill stones. Appropriately chiselled groves on grind stones will help the stones cool down after high-speed milling and prevent them from breaking due to the heat generated at high-speed grinding. Grooving also helps in effective grinding of the grain and thus hastens the the grinding process.

With the objective of bringing about improvements in the way poor communities harness water resources, IT Power India, a renewable energy engineering consultancy firm, upgraded the traditional watermills by making some simple modifications to the design. The upgraded watermills give an output of 20–25 kg flour/ hour in comparison to the 5–10 kg/hour output given by the traditional watermills. 

IT Power India implemented a pilot project in the Chamoli district of Uttarakhand for CWMA (Chamoli Watermill Association) with an initial investment of Rs 60,000 assigned to WMA. As part of the pilot project, IT Power India has undertaken the following activites.

Conducted two training programmes on installation and commission ? of upgraded watermills and demonstrated the working of the upgraded watermills in two districts of Uttarakhand 

Construction 

Conducted training programmes for financial institutions on business ? prospects of upgraded watermills Regularly interacted with watermiller groups and strengthened WMA’s ? awareness on upgraded watermills and helped in their capacity-building activities Published best practice manuals, leaflets, and brochures for promoting ? upgraded watermills. 

Initially, the WMA helped the interested traditional watermill owners in acquiring loans, site appraisal, procuring the hardware and equipment required for upgrading their watermill, and supervising the installation. Originally, the mill owners used to earn an annual income of approximately Rs 3500. With an upgraded watermill, they could earn an annual income of about Rs 17,000 to Rs 22,000. With an almost six-fold increase in their income, watermill owners were able to repay their loans on time and also meet their own needs. 

A traditional watermill can be upgraded at an initial cost of Rs 15,340. This cost is inclusive of hardware, material, and labour costs for civil works; channelGI sheet costs; technical assistance; and installation and commissioning costs. About Rs 2000 per year has to be invested towards meeting the initial expenditure. Loans can be availed from rural and agricultural banks like NABARD for upgrading the traditional watermills. Some nationalized banks and regional rural banks expressed willingness to provide loans for the same, at 12.5% interest and with repayment period of three years. 

It is estimated that at one time there were about 2,00,000 watermills operating across various Himalayan states of India. According to a survey conducted in 2003, there were about 2160 watermills in Chamoli district alone. Out of these, 1150, that is, about 53%, are still functional. Thus, the scale-up potential for the upgraded watermills is very high. 

Upgraded watermills also have a positive impact on health as the loss of nutrients in the process of grinding is very minimal. Diesel-run mills generate more heat while grinding the grain because of their high rotational speed (700 RPM). The large amount of heat generated damages the nutritional quality of the flour. Upgraded watermills generate low heat because of their low rotational speed (200 RPM) and hence retain the nutritional quality. Food prepared using this flour is healthy and tastes better. Women also prefer the upgraded watermills because they need not walk long distances to reach the diesel mills. Their time is also saved as they have to make only one trip to the watermill. 

Upgraded watermills also mean more business for the mill owners. According to a market survey, a single household produces about 270 to 350 kg/year of grain including wheat and millets. As an upgraded watermill is expected to process at least 20,000 kg per year, one watermill can be utilized by 75 to 100 families. 

Upgraded watermills reduce dependency on diesel-run mills thereby reducing the consumption of diesel, which in turn reduces carbon emissions and saves the environment. 

Technologically, upgraded watermills are easy to maintain. In the case of traditional mills, the wooden runner has to be replaced once in two years and the wooden blades have to be tightened once in two or three years. On the contrary, for upgraded watermills, the metallic runner can be used for more than 10 years and only the pin bearing has to be repaired once in two to three months. The efficiency of the watermill would increase further if a nozzle made of PVC pipe is used as water coming through the nozzle would be able to hit the runner more forcefully than the water coming through the wooden chute. 

References-:

1. Ministry of New and Renewable Energy -: https://mnre.gov.in/case-study-success-story