Low cost wind mill for ground water lifting

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Low cost wind mill for ground water lifting

Developed by Md. Mehtar Hussain & Mushtaq Ahmad

Submitted by

Gujarat Grassroots Innovation Augmentation Network Bungalow No. 1, Satellite Complex, Nr. Satellite Tower,

Premchand Nagar Road, Satellite, Ahmedabad Tel: 91-79-26769686, Telefax: 91-79-26760398

email: [email protected], website: www.gian.org

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Model: 1 Static model made from Bamboo/Eucalypts Structural arrangement:

The windmill actuated bore-well pumping unit consisting of a tall tower structure made of two parallel bamboo posts supported by two inclined bamboo posts each. An iron shaft made from iron pipe is mounted on bearings near the top of the tower, ends of which rest on the parallel bamboo posts on either side. At the centre of the shaft, a wind turbine with four blades is mounted. The shaft is connected to the hand pump handle on the ground through mechanical linkages (crank lever mechanism). As the turbine rotates, due to motion of the wind, the shaft also rotates. Through the mechanical linkages, rotary motion of shaft is

converted to reciprocating motion of the lever of the hand pump, which in turn pumps water from the tube well continuously. Fabrication process: It is very easy to fabricate and assembled the entire wind mill. The blade is made from wooden strip (2” x 1” thick babul material) on which aluminum sheet of 27 gauge is mounted. At the center of the shaft, a four-bladed wind turbine is mounted. There are total four triangular shape blade having six feet length (total blade diameter is 13 feet). The blades are mounted at the middle of shaft on rotor made from MS flat which are fixed at particular angle. The iron shaft is mounted through pedestal and bearings near the top of the supporting posts. The angle of the blade is maintained by tightening and adjusting the wire accordingly. All four blades are joined with each other through wire which gives strength to the blades. The shaft is then connected to a hand pump through an iron strip. As the turbine is rotated by the wind, the lever is set in motion and the up and down motion of the pump discharges water. Bill of material and cost break up: Sr. Particulars Specification Amount 1 Wind Blade made from

wooden frame and aluminum sheets (27 guage)

6 feet length x 5 feet width at bottom , triangle shape , 4 numbers

2500/-

2 Pedestal & bearings Dia – 30 mm , 2 No.s 750/- 3 Main Axle 1.25 inch dia GI pipe , 7 feet length 750/- 4 Crank mechanism & its

accessories 1500/-

5 Support structure ( Bamboo or Eucalypts)

a) Main posts -2 No.s - 20 feet long & 4 to 6 inch dia b) Supporting posts - 4 No.s -3 inch dia 18 feet long

2000/-

6 Accessories Not , bolts , nails, wire , etc 1000/- 7 Hand pump unit – 1 with

cylinder (2.5 inch dia) India Mark -II 3500/-

8 Miscellaneous & labour 3000/- TOTAL wind mill cost ( Fifty thousand only) 15000/-

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Advantages

The use of low cost, locally available material instead of costlier metals for the framework and the direct drive to do automatic pumping of water from the tube well has given it an innovative shape.

This entire arrangement is like a portable unit, which can be dismantled in an

hour, and then reassembled and connected to a tube well in another location in almost no time.

Since the supporting framework is made of bamboo (or eucalypts or any local

wood), the final product costs only Rs 15000/-, which is very low as compared to any commercially available conventional windmills.

No RCC or any kind of foundation is requires for installation. The wind mill can

be installed easily by digging hole for erection of bamboo posts.

It is very easy to fabricate this wind mill. Any carpenter or local fabricator can manufacture the blade and install the wind mill with the use of accessories like pedestal, bearing etc. No formal training is requiring for installation of wind mill. Any farmers or local fabricators can easily install the wind mill.

Limitations

It works functions only when the turbine blade faces the wind direction. This wind turbine does not adjusts itself according to the direction of wind flow and therefore selection of position of installation of wind mill is an important step while installation.

Because it is made from light weight material and light in weight, it may not

able withstand high wind velocity. In such situation it may fall down but one can again reinstall it without any major expenses.

There is no any formal arrangement of brake system in the design. The wind

mill can be stopped by inserting the bamboo or any wooden poles in between two blades.

Life and Durability:

The structure is made from bamboo / eucalypts and other light weight material and therefore it has limited life compare to iron structure. However the system minimum last for five years.

Operation and maintenance require:

It only requires lubrication in bearings, tightening the nut bolts & wire etc.

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Model: 1 Static model made from Bamboo/Eucalypt

5

A B

C

Shaft

Flat

Holes

Bearings

Model: 2 Multi directional windmill made from metal Structural arrangement:

This is the modified version of the low cost bamboo windmill with the advantage of changing its direction with the change in the direction of wind. The main components of the windmill are mainframe or structure, blades with tail and a crank mechanism for converting the rotary motion into reciprocating motion. A simple mechanism is used to make the windmill multi directional. At the top of the mainframe a simple arrangement is made to rotate around vertical axis with the help of roller and cylindrical bearing. This multi-directional rotating frame carries the blades, shaft and crank mechanism. In the present design we have directly connected the crank mechanism with the rod which in turn is connected to the cylinder at the bore. Blades are given the proper angle so that the higher wind power can be harnessed and there by can pump the water from

greater depth. Blades are made up of aluminum sheet or MS angle. Wires are used to provide the extra strength to the blades. Fabrication process The total wind mill is made from iron material. The structure is divided into three main components viz; turbine blades with tale, crank mechanism and main frame (support structure). Any fabricator can manufacture the turbine blades and main frame structure from iron materials, but the fabrication of crank mechanism requires engineering skill. Any medium scale engineering job work specialist can fabricate the crank mechanism.

For the conversion of rotary motion in to reciprocating motion, crank and connecting strip mechanism is used. Crank is made in such a way that it can be assemble and dissemble according to the requirement. In order to make crank, two flats having holes are perpendicularly welded with two shafts (Figure A). Now connecting strip with bearing is welded between the holes of flat (Figure B) in order to complete the crank. Figure C shows the complete crank and connecting strip mechanism. Provision of various holes facilitates the adjustment of stroke length of hand pump.

Assembling of the windmill is quite easy as it is fabricated in three main pieces. It can be assemble easily by joining three components each other with nuts and bolts to be tightened to erect the structure.

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Bill of material and cost break up: Sr. Particulars Specification Amount 1 Wind Blade made from iron

frame and aluminum or MS sheet (27 gauge) with tale

6 feet length x 5 feet width at bottom, triangle shape - 4 numbers

3000/-

2 Crank mechanism with rotor plate for mounting blades

Four pedestal bearing , two thrust bearings , C channel, rotor plate

8000/-

3 Support structure

Made from MS angle & Strip 4000/-

4 Hand pump cylinder 2.5 inch dia, brass or SS material 1000/- 5 Nut bolts, universal joints ,

guiding bush for rod, wire 1000/-

6 Plumbing material & accessories

2000/-

7 Fabrication charges , labor etc

6000/-

Total Wind mill cost ( Twenty Five thousand only) 25000/- Advantages

This wind turbine adjusts itself according to the direction of wind flow and therefore it gives continuous discharge.

This entire structure is made from iron material and hence it withstands high

wind velocity and adverse situation.

Stroke length can be adjusted through crank mechanism. Simple crank arrangement does not require any major and expensive maintenance.

Limitations

RCC or Pakka foundation is must for installation. Life and Durability:

This entire structure is made from iron material and hence it withstands high wind velocity. The life is more than 10 years. It is very sturdy and durable in nature & does not damage easily.

Operation and maintenance require:

Nit does not require any maintenance except regular lubrication in bearings, tightening the nut bolts etc.

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Model: 2 Multi Directional wind mill made from metal body

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About the Innovator & Genesis of Innovation:

Md. Mohhand Mehtar Hussain (38) and Mushtaq Ahmad (28) are resident of Darrang, Assam. Looking for a low-cost alternative to pump water in the fields for the winter crops, they have devised simple windmill made up of bamboo and tin sheets. Married, with one son, Mehtar lives in a joint family with his widowed mother, one sister and brother. The family

owns two acres of land, which the two brothers jointly look after. Both have completed their education up to higher secondary and since then have been practicing agriculture. They produce just enough paddy for their own consumption, with a little surplus in some seasons. The main source of income for the family is a pension of about Rs. 2,500 per month in the name of his late father, who had retired as a Primary school teacher. Though economically poor, theirs is a happy and close-knit family. Though the water table is not too deep, but drawing water is not easy since electricity supply is erratic and most small farmers can not afford other means also. Mehtar and his brother while growing paddy in winter season (also called bodo paddy), needed irrigation from the well. Continuous pumping by hand involves a lot of effort and drudgery. At the same time, pumping out water by using diesel sets was a big drain on their resources. He pondered over the problem and looked around for a solution.

It was after a while when his sharp eyes started minutely observing the working of sewing machine. He noticed that the circular movement of the hand drive wheel caused the up and downward movement of the needle. This formed an image in his mind, which was the genesis of the solution that he was going to come up with. One fine day, while resting on the lush grass by the side of his field and lazily watching the clouds, he observed a kite in the sky. A sudden gush of wind soared it high in the sky, which triggered the thought of harnessing wind power in some way as a component of the solution he had in mind. He concluded that if he could develop a large wheel, which could run on wind power, and connect this wheel (turbine) to the handle of the hand pump, he might pump out water continuously as the turbine rotates. Getting a base of available hand pumps to experiment on was not a problem.

In the 1990s, NABARD had done a lot of tube well boring in the district, as a part of their subsidy scheme to promote winter cropping and this became the experimentation platform for these brothers. Both of them then started building a windmill unit, using locally available materials such as bamboo, wood, strips of old tyres, pieces of iron, etc. Although they had never seen a windmill before, they were able to develop the windmill in no time and the first prototype became functional in only four days with the help of a local carpenter. This was possible because the brothers had constructively debated long on the form that they wanted for the turbine and had put down everything on paper.

Shri Mehtar Hussain and Mushtaq Ahmad have been awarded National Award by National Innovation Foundation for this development in 4th Annual Award Function held on 11th February 2007 at New Delhi.

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Current Status:

Installation in North East Area:

Innovator Shri Mehtar Hussain has installed about 7 units in North East region. Centre for Energy, Indian Institute of Technology Guwahati has done the technical analysis and feasibility study in the year March 2007. The copy of the report is enclosed herewith in Annexure: 1. As per the report, the performance of the wind turbine installed at Mahariapathar was found to be the best giving a maximum discharge of 60 liter/min at 3.2 m/s. In the report, the scientist also made recommendation to increase the performance of the wind mill.

Demonstration: 1 At Little Runn of Kutchh for lifting ground water for salt farming

Looking at the vast potential and relevance of the technology for salt farmers, GIAN, Ahmedabad, regional incubator of NIF organized a technology demonstration program of various innovations for salt growers group of VIKAS, Ahmedabad where the they highly appreciated the low cost wind mill developed by Shri Mehtar Hussain and requested GIAN and VIKAS to demonstrate the actual product in the Little Runn of Kutchch. GIAN Ahmedabad coordinated with Assam based partner (i.e. NIF cell, North East) and invited the innovator to install the device in Dhangadhra region. On demonstration basis, during the period of January 2008 to May 2008 , we have installed two wind mills at Boda village of little desert of Kutchh, Near Dhangadhra in association with VIKAS & SAVE (Saline Area Vitalization Ltd), Ahmedabad based NGO’s working for empowerment of salt farmers in Gujarat. The performance of the experimental setup has been overwhelming and the farmers have appreciated and shown their interest in buying such units. According to them it is a very cheap and efficient alternative for irrigating saltpans compared to conventional method of lifting ground water through diesel pumps. At these prices of crude oil (US$100/barrel), it takes 65 to 70 thousand rupees to produce 500 tons of salt. Of this, around 50 to 55 thousand rupees alone would go in meeting energy related expenses like crude oil, pump maintenance and interest payment on working capital for meeting crude oil expenses. Replacing the crude oil engine with windmill driven hand pump would completely overhaul economics of inland salt making. Thus this one single intervention has potential to increase net income of inland salt makers manifold. A field test was carried out by installation of two such wind mills at saltpans of Shri Maghbhai and Shri Premjibhai Muladiya, at Boda desert, Dhangadhra, Gujarat Performance Data:

Output: Minimum 50 Lit / Min (3000 lit / hr)@ wind speed >15 km/hr, If we get average wind speed for at least for 15 hr/ day , we will get about 45000 lit day.

Average requirement of water by a farmer is about 80,000 lit, therefore 2 wind

mills/farmer fulfills their requirement

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Demonstration: 2 Installation of low cost wind mill at Sasan Gir (Dist: Junagadh)

Looking to the success of wind mill demonstration at Little Runn of Kutchh, AKRSP (Aga Khan Rural Support Program), a well know international level NGO approached GIAN with request for demonstration in Junagadh district of Gujarat, for irrigation purpose. We have installed one unit of wind mill (Model: 2, Multi direction model) at village: Bhalchhel, Taluka: Talala, District: Junagadh). We have installed this wind mill on 24th May 2008 and it is working satisfactory. We have recorded observation at site for six days continuously. The test report is enclosed herewith. On an average, the water output is 2000 lit /hr @ 12 km / hr wind speed. Further Scope of Value Addition: We have identified following areas for research and value addition in order to make the wind mill more efficient, durable and make it more affordable.

1) Aerodynamic shape to the blade design and material study 2) Incorporation of clutch / brake system to stop turbine 3) Incorporation of gears or efficient design of crank mechanism 4) Durability and efficiency 5) Micro power generation thorough use of battery & inverter

GIAN team and innovator are working on various designs considering above points. Cost Aspects: The cost of manufacturing this wind mill in Assam is much lower (About Rs. 8000 to 10000/-) because of availability of bamboo at cheaper rate. The cost of manufacturing model-1 (Static model made from Bamboo/Eucalypts) is about Rs.15000/- (Fifteen thousand only) and cost of model 2 (Multi direction model made from metal) is around Rs.25000/-(Twenty Five Thousand) only, which is too less (more than 50 % lower) compare to other conventional wind mill available in the market. The cost may increase or decrease depending upon the availability of raw material and quality. It is an environment friendly product with low initial cost, zero operating cost and has great relevance in today’s world. Since it is fitted to a tube well, it meets the needs of light irrigation and potable water too. It is also important to note that in both the models, we can easily arrange the clutch or break system but ultimately it will add to the cost. According to users, it is very convenient for them to lock the wind mill through string. We will incorporate the clutch or brake mechanism in next model as an option for farmers. ---------------------------------------------------------------------------------------------------------- Encl: Annexure: 1 Test Report by IIT Guwahati for Model: 1 Annexure: 2 Test Report by GIAN for Model: 2

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Annexure: 2 Test report Windmill (Model 2) Site Installed: Village-Bhalchhel, Taluka- Talala, District-Junagadh GIAN representative record observations of windmill on site for the six days. Data were recorded from morning to evening. An anemometer and a container of known volume were used for measurement of wind velocity and discharge respectively. Time was measured using stop watch. For discharge measurement, a container of 16 liter was kept below the outlet (hand pump out let) and time was measured for filling the container. Simultaneously wind velocities were measured by digital anemometer for every variation of wind velocity during the filling of container. Then average of wind velocity was calculated for discharge of 16 liter. Table: Observation of Wind Velocity, Discharge & Time:

Time ( Hrs) Sr.No. Date

AM

PM

Average Wind Speed

Time Taken for Discharge

of 16 liter container

1 27.05.08 9 8.8 49 2 27.05.08 10 7.3 48 3 27.05.08 11 9.7 49 4 27.05.08 12 10.5 43 5 27.05.08 1 7.4 53 6 27.05.08 2 7.0 46 7 27.05.08 3 9.0 53 8 27.05.08 4 7.9 50 9 27.05.08 5 4.7 60

10 27.05.08 6 5.7 65 11 28.05.08 9 7.0 60 12 28.05.08 10 8.5 45 13 28.05.08 11 9.5 40 14 28.05.08 12 10.5 35 15 28.05.08 1 11.0 30 16 28.05.08 2 12.0 27 17 28.05.08 3 11.5 29 18 28.05.08 4 7.5 48 19 28.05.08 5 8.0 46 20 28.05.08 6 7.0 55 21 1.06.08 9 10.5 35 22 1.06.08 10 5.7 70 23 1.06.08 11 6.5 57 24 1.06.08 12 8.2 45 25 1.06.08 1 5.6 80 26 1.06.08 2 7.1 49 27 1.06.08 3 5.3 60 28 1.06.08 4 6.4 46 29 1.06.08 5 6.9 50 30 1.06.08 6 9.6 40

12

31 2.06.08 9 4.0 75 32 2.06.08 10 5.4 70 33 2.06.08 11 7.2 45 34 2.06.08 12 7.6 43 35 2.06.08 1 7.0 50 36 2.06.08 2 7.4 50 37 2.06.08 3 8.0 65 38 2.06.08 4 6.6 49 49 2.06.08 5 6.7 51 40 2.06.08 6 4.8 50 41 3.06.08 9 7.8 50 42 3.06.08 10 9.2 48 43 3.06.08 11 6.4 49 44 3.06.08 12 8.0 50 45 3.06.08 1 6.3 64 46 3.06.08 2 6.4 53 47 3.06.08 3 5.8 52 48 3.06.08 4 7.0 56 59 3.06.08 5 7.7 60 50 3.06.08 6 4.9 54 51 4.06.08 9 4.7 55 52 4.06.08 10 7.2 52 53 4.06.08 11 6.3 58 54 4.06.08 12 5.1 760 55 4.06.08 1 7.4 53 56 4.06.08 2 6.6 51 57 4.06.08 3 7.8 49 58 4.06.08 4 9.5 40 69 4.06.08 5 5.7 69 60 4.06.08 6 9.4 44 61 5.05.08 9 5.5 65 62 5.05.08 10 7.5 46 63 5.05.08 11 9.7 41 64 5.05.08 12 4.3 57 65 5.05.08 1 5.0 70 66 5.05.08 2 6.5 58 67 5.05.08 4 10.8 36 68 1.06.08 5 7.1 57 79 1.06.08 6 5.5 65

Total 508.1 4273

Conclusion: By the calculation it was found that

Average discharge was 1064.7 liter/ h @ 6.43 km/h (average) of wind velocity Maximum discharge 2133 liter/h @ was 12 km/h (average) wind velocity

Technical Assessment Of The Wind Turbine-Cum-Water Pump System Developed By Mehtar Hussain

(A Consultancy Project)

Sponsored by

GIAN – North East National Innovation Foundation, India

Indian Institute of Technology Guwahati

PROJECT COMPLETION REPORT

Investigators

U. K. Saha Associate Professor of Mechanical Engineering P. Mahanta Associate Professor of Mechanical Engineering

& Head, Centre for Energy S. K. Dwivedy Associate Professor of Mechanical Engineering P. Kalita Scientific Officer, Centre for Energy

Centre for Energy Indian Institute of Technology Guwahati

March 2007

INTRODUCTION

Availability of water supplies is not a problem in north-east region of India. However, the availability of power supplies in the open range is often limited, so some alternative form of energy is required to convey water from the source to a point of utilization. Wind energy is an abundant source of renewable energy that can be exploited for pumping water in remote locations and wind turbine are one of the oldest methods of harnessing the energy of the wind to pump water [1-9]. The aforementioned technique was used by one of the villagers, MD. MEHTAR HUSSAIN from Sipajhar area of Assam. The idea and the system he employed is of great importance and is very much impressive. A system that requires only wind to operate and properly installed and maintained can serve the purpose of small-scale cultivation. For most developing countries renewable energy has been identified as an attractive alternative for solving their problems [1, 2].

GIAN, North-East, which is an incubator of grassroots innovations and traditional knowledge and Indian Institute of Technology Guwahati jointly involved themselves in the overall technical assessment of this wind turbine cum pumping system which has been installed at several locations near Sipajhar. BACKGROUND THEORY

Windmill efficiency: The terms windmills and wind turbines can be used synonymously. Turbines are a means of harnessing the fluids power by converting the kinetic energy of the fluid (the wind) into mechanical power (the rotating shaft). It is the flow of air over the blades and through the rotor area that makes a wind turbine function. The wind turbine extracts energy by slowing the wind down. Wind turbines, theoretically at the most, can extract only 16/27th (59%) of the kinetic energy from the wind. This is called Betz Limit and can be mathematically proved [3, 9].

Height of wind-turbine: In calculating the height of the wind turbine it is important to keep in mind that the wind turbine must be high enough to be above obstructions. The wind velocity decreases as one approach the surface. This means that the higher you build, the better chance there will be that the wind speed is higher, however, you must always be aware of the strength of the support on which turbine is mounted. The approximate increase of speed with height for different surfaces can be calculated from the following equation:

2 2

1 1

.v h kv h

= (1)

where v1 is the known (reference) wind speed at height h1 above ground, v2 is the speed at a second height h2 and k is the exponent determining the wind change. Values for k are listed in the Table-1, for different types of wind cover [4, 9].

Table-1

S. No. Ground Cover k

1. Smooth surface, ocean, sand 0.10 2. Low grass or fallow ground 0.16 3. High grass or low row crops 0.18 4. Tall row crops or low woods 0.20 5. High woods with many trees suburbs, small towns 0.30

Locations: The primary consideration in choosing a site for wind turbine is whether there is sufficient wind for such a device to be feasible. Vegetation and other geographic characteristics can result in large variation in available wind power over short distances. To ensure that the wind turbine receives a free flow of air from all directions, the rotor of a wind turbine should be located at least 5 to 6m (15 to 20 ft) higher than any obstructions within about 130 to 180 m (450 to 600 ft) of the wind turbine site. In fact, as pointed above, wind speed increases with increase in altitude, so the tower should be as high as reasonably possible, regardless of the presence of obstruction [1]. Pumps: The most common types of pump used in wind turbine pumping system is the positive- displacement cylinder pump (Fig.1) driven by a reciprocating rod connected to a gear box at the turbine rotor. The performance of these pumps can be enhanced through the addition of springs, cams and counter weights that alter the stroke cycle and off-set the weight of the drive rod, thereby reducing the starting torque and allowing the system to perform better in light winds [1].

Water Delivery: The amount of water a wind powered water pumping system can deliver depends on the speed and duration of the wind, the size and efficiency of rotor, the efficiency of the pump being used and how far the water has to be lifted. The power delivered by a wind turbine can be determined from the following equation [1].

2 30 .0109P D V η= (2)

where, P - Power in watts D - Rotor diameter in meters V - Wind speed in km/hr

η - Efficiency of wind turbine

However, the efficiency of wind turbine decreases significantly in both low and high wind speeds [1]. The following chart (Fig. 2) shows one way in which manufacturers present information relating to performance of their products.

Maintenance of the set-up: One of the attractive features of a wind powered pumping system is its simplicity and robustness. It is prudent to check all rubber diaphragms annually. The anchoring system for the wind turbine should also be checked to ensure that wind turbine is not toppled during high speeds [1].

Fig.1 Typical windmill pump cylinder [1]

Fig.2 Variation of discharge with wind speed [1]

THE WIND TURBINE CUM WATER PUMP SYSTEM

The wind turbine developed by Mr. Hussain consists of two parallel supporting posts made of bamboo, which are themselves supported further by two inclined bamboo posts (Figs. 3 and 4). An iron shaft is mounted on bearings near the top of the supporting posts. At the center of the shaft, a four-bladed wind turbine is mounted. The shaft is then connected to a hand pump through a lever ball bearing system. The lever is divided into two parts for better efficiency. As the turbine is rotated by the wind, the lever is set in motion, and the up and down motion of the pump discharges water (Fig. 5).

Fig.3 Front view of the wind turbine Fig.4 The side view

Fig.5 Schematic diagram of the setup

Fig.6 Measurement of blade angle

The blade angle of the wind turbine is illustrated in Fig. 6. The point A and C in two consecutive blades are at the same level, while B is at a lower level due to inclination of the blade surface. This blade angle varies from 70 to 100 in the developed turbine systems.

ROAD MAP FOR THE INVESTIGATION

• Measurement of wind speeds at different time periods.

• Calculating the rotational speed of the turbine at different wind speeds.

• Record of various parameters like blade hub-diameter, blade tip-diameter, number of blades, pump used, ground water level etc.

• Measurements of pump discharge over the tested range of wind speeds.

• Extensive study of experimental data.

• Investigation of the pump performance in terms of wind speed.

Finding pros • and cons of the system, and suggest suitable design

• chnical assessment of the system, design modifications and recommendations.

modifications.

Report preparation based on data collection, data analysis, te

ME SU

a.

of anemometer does not vary over the entire duration of the

b.

ne. This will cause a

c. ssary to take sufficient data over a

range of time, which were then averaged.

A REMENT PROCEDURE

An anemometer as shown in Fig. 7 was placed in the direction perpendicular to the turbine rotor at some distance from rotor (approx. 2 m). It was ensured that the position experiment. The anemometer was placed at a height of 2 m (average) above the ground whereas the wind turbine was situated at a height of 3.5 m to 4.0 m. There will be difference in speed of wind at the point where wind turbine is situated and at the point where wind speed measurement is being doslight change, however, the trend will remain the same. As the wind speed changes continuously and as the anemometer shows instantaneous speed of wind, it was nece

d. The anemometer also displays the ambient temperature at the various moments of time, and they were also noted down.

e. The rotational speed of the shaft was measured with a non-contact type tachometer (Fig.8).

f. A stopwatch was used for measuring the time (Fig. 9) during the course of the experiments.

g. The pump discharge was collected in a bucket, and the volume of discharge was obtained with the help of a standard beaker as shown in Fig. 10.

h. An alternate way to measure the rotational speed of shaft is to measure the overall back and forth motion of slider in the sliding groove during each observation (Fig. 11) of the experiment. One back and forth motion accounts for one crank rotation. Thus, in one observation, number of rotation of crank = number of back and forth motion of slider.

Fig.7 Anemometer Fig.8 Tachometer

Fig.9 Stopwatch Fig.10 Beaker

Fig.11 Slider crank mechanism

DATA COLLECTED FROM THE EXPERIMENTS

At the end of each experimental observation, the following data were recorded: 1. Wind speed 2. Temperature (ambient) 3. Shaft rotation speed 4. Volume of discharge 5. Time span of observation

PRECAUTIONS TAKEN

• Before the start of any observation, the pump leakage was reduced to a minimum as much as possible.

• A proper examination of lubrication of slider (in groove) and pump handle was done.

• The anemometer was used at some specific position and height in every observation. It was held firmly so that the error in wind measurement was minimum.

• In some sites, when the pump discharge was found maximum, it was ensured that there was no spillage of water during changing of bucket.

DATA SHEET FOR WIND TURBINE CUM WATER PUMP

Table-2: Specification of turbine and pump at Mahariapathar

Sl. No. Particulars Remarks

1 Hub diameter of the turbine : 58 cm

2 Tip diameter of the turbine : 382 cm

3 No. of blades : 4 (Four)

4 Blade dimensions : Trapezium (160-143-160-36) cm

5 Blade Material : Aluminium

6 Thickness of the Blade : 0.5 mm

7 Blade Angle : 7.23 degree

8 Construction Material : Wood, Bamboo, Aluminium, Mild Steel

9 Wind Direction : East-West

10 Crank Length : 20 cm

11 Wind turbine height from ground : 325 cm

12 Ground water level : 18-20 feet (as reported)

Table-3: Specification of turbine and pump at Sipajhar





4 Blade dimensions : Trapezium (159-144-159-43) cm






10 Crank Length : 17.35 cm



Table-4: Specification of turbine and pump at Kaniatari





4 Blade dimensions : Trapezium(152.5-141.5-152.5-27) cm






10 Crank Length : 20 cm



RESULTS AND DISCUSSION

Figures 12, 13 and 14 show the performance characteristic of wind turbine cum pump system at Mahariapathar. The following observations have been made:

• The discharge of 60 lit/min is found to be maximum at a wind speed 3.2 m/s. The trend however, does not fully match the ideal trend (Fig.2).

• The discharge continuously increases with wind speed reaches maximum at a certain wind speed and then falls continuously with the increase wind speed. The similar behavior has been observed in the case of discharge with rotor speed. The continuous increase is obvious from Fig.12 and Fig.14, but continuous decrease in discharge is not clear as the speed of wind was not enough to show the trend.

• At some points, where discharge should have increased with wind speed, it shows a reverse trend. This is because sometimes one or more of the variable depends on nature and varies randomly, and cannot be controlled.

• The rotor speed increases continuously with wind speed. However, it decreases at some points as shown in the Figures. This can be attributed to several reasons like fluctuations in wind speed, change in direction of wind speed etc.

Wind Speed Vs Discharge

0

10

20

30

40

50

60

70

1 1.5 2 2.5 3 3Wind Speed (m/s)

Dis

char

ge (L

it/m

in)

.5

Fig.12 Discharge Vs wind speed

Wind Speed Vs Rotor Speed

10

15

20

25

30

35

40

45

1 1.5 2 2.5 3 3.5Wind Speed (m/s)

Rot

or S

peed

(rpm

)

Fig.13: Rotor speed Vs wind speed

Rotor Speed Vs Discharge

0

10

20

30

40

50

60

70

10 15 20 25 30 35 40 45Rotor Speed (rpm)

Dis

char

ge (L

it/m

in)

Fig.14 Discharge Vs rotor speed

Figures 15 and 16 depict the performance characteristic of the setup installed at Sipajhar. The observations from this site could be summarized below:

• Discharge Vs wind speed graph is quite satisfactory. The trend of the discharge is increasing with wind speed. The profile still has not reached its maximum as wind speed was not enough, and therefore, the later portion of graph i.e. the decreasing trend is also absent here.

• Rotor speed increases continuously with wind speed – showing the actual trend.


2

4

6

8

10

12

14

16

1.5 2 2.5 3Wind Speed (m/s)

Dis

char

ge (L

it/m

in)

3.5

Fig.15 Discharge Vs wind speed


25

30

35

40

45

50

1.5 2 2.5 3 3.5Wind Speed (m/s)

Rot

or S

peed

(rpm

)

Fig.16 Rotor speed Vs wind speed

Figure 17 and 18 show the performance evaluation of wind turbine cum water pump installed at Kaniatari. It has been observed that the installation of the wind turbine at this location is not at a desirable position for the system to work properly and efficiently. In the vicinity, there are trees, houses that offer hindrance to free flow of wind. The leakage was more than enough in the pump, and also the wobbling in pump handle was more causing a loss of energy. Wobbling is due to misalignment of slider and pump handle, which in turn is due to large lateral distance between them. Due to unavailability of enough data, the plots profile are not good enough, however, they show an increasing trend of discharge with wind speed.


7

7.5

8

8.5

9

9.5

10

1.5 2 2.5 3 3.5 4 4.5Wind Speed (m/s)

Dis

char

ge (L

it/m

in)

Fig.17 Wind speed Vs Discharge


25

25.4

25.8

26.2

26.6

27

1.5 2 2.5 3 3.5 4 4.5Wind Speed (m/s)

Rot

tor S

peed

(rpm

)

Fig.18 Wind speed Vs rotor speed

COMPARATIVE ASSESSMENT

Figure 19 shows the comparison of the system at the three locations viz. Mahariapathar, Sipajhar and Kaniatari. From this figure, it is seen that the performance of the turbine installed at Mahariapathar is significantly higher than that of the other two. This may be attributed to the following:

• The water level i.e. depth of water level from the ground is lesser (18-20 ft) compared to the turbine installed at Sipajhar (28-30 ft) and Kaniatari (35-40 ft). The data against depth of water level as quoted above are only the reported values.

• The system was installed in an open area - free from obstruction.

• Better performance of the pump (i.e. complete suction stroke) resulting in high discharge.


0

10

20

30

40

50

60

2 2.2 2.4 2.6 2.8 3Wind Speed (m/s)

Dis

char

ge (L

it/m

in)

MahariapatharSipajharKaniatari

Fig.19 Performance comparison of wind turbine

RECOMMENDATIONS

The following recommendations have been proposed for an improved version of the wind turbine-cum-water pump system:

1. The wind turbine has to be installed in an open space so that there is no interference with free flow of air.

2. Wobbling of pump handle should be minimum for an optimum output. To minimize the wobbling, slider with connecting rod has to be connected directly above the pump handle.

3. Special emphasis should be given in designing the crank to provide complete suction stroke. Partial suction stroke leads to a decreased flow rate of water.

4. It is recommended that before installation of such a system, it is essential to know the water level of that place. The water level beneath earth surface plays an important role in volume flow rate of water. A large lift to water will cause less discharge to come out thus reducing efficiency. Therefore, it is advisable to install the system in an area where water level is not too far away from the earth surface.

5. A wind turbine that adjusts itself according to the direction of wind flow increases the efficiency of system. However, it involves additional complexities in the system to make it irrespective of wind direction.

6. All the blades of turbine must be of similar size and constructed from identical material. The deviation in dimensions must be kept to a minimum.

7. The angle of all turbine blades was found to be around 8.50. In order to obtain a better performance, the angle incorporated in wind turbine blades should be around 120 to 140.

8. Bearing should be used in slider while it moves in the groove. The turbine at Mahariapathar has this feature, but not the system at Sipajhar.

9. The weight of the turbine blade should be reduced a little. 10. Connection between different wooden rods is not perfect, and this resulted in

more wobbling. The following joint (Fig. 20) has been suggested to gain an improved performance.

11. The two important components, specially the slider and the pump handle, should be lubricated effectively.

12. Sometimes, by using gear the speed of rotation of shaft to which crank is fixed can be increased. This will cause the turbine to work more efficiently when the wind speed is lower. When gear is used there will be two shafts, one on which turbine blade is fixed and on other crank is fixed and they both connected with each other through gear. However, the system is prone to damage at higher wind speeds.

Fig.20 Joint enhancement for reduction of slack

CONCLUDING REMARK

In this project, a technical team of IIT Guwahati visited four different places viz. Mahariapathar, Sipajhar, Kaniatari and Dalgaon where the wind turbine cum water pump system was installed. Detailed investigation was carried out at three locations except the one at Dalgaon, where the system was not working because of high water level. Also, the pump used at this site was very hard requiring greater force and yielding lesser discharge. The performance of the wind turbine installed at Mahariapathar was found to be the best giving a maximum discharge of 60 liter/min at 3.2 m/s. It has been observed that the overall performance of the system depends on the performance of both the wind turbine and the water pump. In order to gain a better performance, some modifications in the existing design have been suggested above.

ACKNOWLEDGEMENTS

We would like to thank GIAN-NE, IIT Guwahati for providing complete funding for the consultancy project entitled “Technical Assessment of the Wind Turbine-cum-Water Pump System Developed by Mehtar Hussain”. The financial support extended is gratefully acknowledged. We would also like to thank Dr. Natabar S. Hemam, Co-ordinator, GIAN-NE for his cooperation during the course of the project.

REFERENCES

[1] http://www.agr.gc.ca/pfra/water/wind_e.htm

[2] http://earthsci.org/mineral/energy/wind/wind.html

[3] http://www.energy.iastate.edu/renewable/wind/wem

[4] Badran, O, 2003, Wind Turbine Utilization for Water Pumping in Jordan, Journal of Wind Engineering and Industrial Aerodynamics, Vol. 91, pp. 1203–1214.

[5] Rotta, J. L., and Pinilla, A., 2007, Performance Evaluation of a Commercial Positive Displacement Pump for Wind-water Pumping, Renewable Energy, Vol. 32, pp. 1790–1804.

[6] Smulders, P. T., and Jongh, J. D. 1994, Wind Water Pumping: Status, Prospects and Barriers, Renewable Energy, Vol.5, pp. 587-594.

[7] Valde`sa, L. C., and Ramamonjisoa, B., 2006, Optimised Design and Dimensioning of Low Technology Wind Pumps, Renewable Energy, Vol. 31, pp. 1391–1429

[8] Vishwakarma, R., 1999, Savonius Rotor Wind Turbine for Water Pumping - An Alternate Energy Source for Rural Sites, Journal of Institution of Engineers (India), Vol.79, pp. 32-34.

[9] Walker, J.F., and Jenkins, N., 1997, “Wind Energy Technology,” John Wiley and Sons.

http://www.agr.gc.ca/pfra/water/wind_e.htm

http://earthsci.org/mineral/energy/wind/wind.html

APPENDIX – TEST DATA

Table-A: Test Data (Mahariapathar) - Date: 15/12/2006

Time Velocity (m/s) Discharge (Liter/Min)

Rotor speed (RPM)

Ambient temp. (0C)

1.80 22.556 22.100 25.5

2.96 42.614 35.790 25.5

12 Noon

2.28 30.612 27.551 25.5

3.34 46.428 37.857 27.0

3.06 58.988 41.797 27.0

2.00 PM

2.32 38.461 33.846 27.0

Table-B: Test Data (Mahariapathar) - Date: 27/01/2007

Time Velocity (m/s)

Discharge (Liter/Min)

Rotor speed (RPM)

Ambient temp. (0C)

2.47 42.857 37.714 23.0 10.00 AM

2.50 44.118 38.823 23.0

1.48 17.857 17.857 25.0

2.90 31.780 29.491 25.0

12 Noon

3.25 47.124 37.058 25.0

2.94 38.462 33.077 27.0

1.07 14.545 11.818 27.0

2.00 PM

3.11 57.692 420692 27.0

Table-C: Test Data (Mahariapathar) - Date: 10/03/2007

Time Velocity (m/s)


Rotor speed (RPM)

Ambient temp. (0C)

2.66 49.882 38.353 24.5

1.54 26.000 25.000 24.5

12 Noon

1.81 24.000 22.000 24.5

1.86 31.915 28.085 26.0

1.78 18.545 18.545 26.0

2.00 PM

2.12 36.206 33.103 26.0

Table-D: Test Data (Sipajhar) - Date: 10/03/2007

Time Velocity (m/s)


Rotor speed (RPM)

Ambient temp. (0C)

1.72 3.692 27.692 28.0 10.00 AM

1.85 3.750 30.000 28.0

2.75 8.048 36.585 30.0

2.94 13.571 45.712 30.0

12 Noon

2.20 6.164 32.875 30.0

2.40 7.105 34.736 31.0

2.57 7.279 36.176 31.0

2.00 PM

2.16 6.600 32.000 31.0

Table-E: Test Data (Kaniatari) - Date: 15/12/2006

Time Velocity (m/s)


Rotor speed (RPM)

Ambient temp. (0C)

3.15 7.930 25.846 26.0

4.10 9.210 26.250 26.0

12 Noon

3.00 8.299 15.794 26.0

3.25 9.484 26.510 28.0

2.50 9.273 26.182 28.0

2.00 PM

1.96 8.123 25.846 28.0

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Low cost wind mill for ground water lifting

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