Introduction of Animal Powered Cereal Mills (GTZ, 1996, 70 p.) Annex 1. Technical foundations for the evaluation of animal-powered mills 2. Curriculum for project implementation 3. Comparison of the economic efficiency of animal-powered mills and motor mills (100 FCFA <= 0.33 $ US) 4. List of the studies, reports an brochures elaborated within the framework of the project 5. Source documentation of figures 6. Contact addresses

Introduction of Animal Powered Cereal Mills (GTZ, 1996, 70 p.)

Annex

1. Technical foundations for the evaluation of animal-powered mills

Output

The theoretical and the actual output of animal-powered mills are not identical. The calculation of the theoretical output is based on the assumption of a continuous, constant and faultless operation of the mill, whereas the actual output is usually lower because of interruptions in work, set-up times, fatigue of the animals etc.

The theoretical output is determined by grinding a small amount of grains (1-2 kg), timing the grinding process and calculating the value for one hour. The determination of the actual output should be based on monitoring the work for several days. Then the daily flour quantity must be related to the daily working time.

The employment of "bicycle computers" as measuring instruments has proved successful.

They store the total of wheel revolutions and the time during which the mill actually works.
This method is helpful not only for the precise determination of the theoretical output, but also for the identification of frequent disturbances, rapid fatigue of the animal, bad organisation of work etc., if the daily working time and flour quantity are recorded, too.

Fig. 1: Particle-size distribution curve of two different types of flour with the same fineness index (I = 724). However, when touching, flour 2 is considered to be more coarse because it is more inhomogeneous than flour 1.

Fig. 2: (1) Particle-size distribution curve of a flour type, which is suitable for the preparation of the millet dish To according to a Mali housewife
(2) Particle-size distribution curve of a flour suitable for the preparation of couscous, according to the same housewife.

Flour quality

The decisive criterion for the evaluation of the flour quality is the fineness It can be described by means of a flour particle size distribution curve, which is determined by sieving the individual fractions using sieves with mesh widths 1.4 mm, 0.8 mm, 0.4 mm and 0.2 mm. With the help of the particle-size distribution curve the homogeneity of the flour can be determined (Figs. I, 2). The particle-size distribution curve of the flour produced with the help of the animal-powered mill should be similar to that produced traditionally in the respective region.

The numerical value of the flour fineness is usually given as the average size of the flour particles and the deviation of particles from this average size. However' this method does not give any information as to the power required for the production of a certain flour type.

This information can be obtained using the formula developed by the Institut Technologique Dello for the calculation of a fineness index. It is based on the hypothesis that the power required for grinding is in proportion to the enlargement of the surface resulting from grinding. The enlargement of the surface' on its part, is in proportion to the reduction of the diameter. This results in the following fineness index for millet:

Imillet = d1/d1 x P1 + d1/d2 x P2 + d1/d3 x P3 + d1/d4 x P4 + d1/d5 x P5 - 100

d is the average diameter of the particles of the respective fraction. d1 is the average diameter of the unground millet.

Furthermore, the following applies:

P1: portion (%) of the particles :> 1.4 mm
P2: portion (%) of the particles < 1.4 mm, > 0.8 mm
P3: portion (%) of the particles < 0.8 mm, > 0.4 mm
P4: portion (%) of the particles < 0.4 mm, > 0.2 mm
P5: portion (%) of the particles < 0.2 mm

If d1 = 1.5 mm hence it follows

I_millet = 1 P1 + 1.36 P2 + 2.5 P3 + 5 P4 + 15 P5- 100

For Sorghum and maize bigger sieves should be used additionally.
For Sorghum (d, = 3 mm) the following holds

I_sorghum = 1 P1 + 1.43 P2 + 2.73 P3 + 5 P4 + 10 P5 + 30 P6 - 100

with P1: portion (%) of the particles > 2.8 mm,
P2 - P6 corresponds to P1 - P5 for millet, with
P2> 1.4 mm < 2.8 mm

For maize (d1 = 6 mm) the following holds

I_maize = 1 P1 + 1.43 P2 + 2.86 P3 + 5.46 P4 + 10 P5 + 20 P6 + 60 P7- 100

with P1: portion (%) of particles > 5.6 mm
P2: portion (%) of particles > 2.8 mm
P3 - P7 corresponds to P1 - P5 for millet

2. Curriculum for project implementation

Phase	Field of problems	Investigation and counseling tasks	Participants
Feasibility study	Organisation of the use of the power gear	- examine in how far women's groups already exist and which organisation structures they have	women, rural population, women's projects
		- judge the dynamics and readiness for innovations
		- examine the traditional organisation of work
		- determine the potential user circle
	Acceptance/ economy	- examine prior experience with motor mills	women, rural population, notabilities, administration, political decision makers, projects in the field of food technology
		- establish a public image on the question“motor or animal powered mill" with particular regard to influential persons (chiefs, missionaries, etc.)
		- examine in how far resistance on the part of the men and women against the use of draft animals by women is to be expected
		- determine the necessary processing capacity and the processing peaks which must be covered by the capacity of the mill
	Draft animals	- register available draft animals, find out disposing powers	rural population, veterinary medical services, projects in the field of animal power craftsmen, projects for trade promotion
		- examine the feeding condition of the animals
	Production	- examine whether local craftsmen would be able to produce power gears
Preparation of the demonstration phase	Executing agency	- identification of a suitable location for a test and demonstration programme	projects and organisations in the field of
		- identification of potential executing agencies	- animal power
		- women
		- appropriate technology
		- promotion of artisans
		- rural development
		- food technology
	Draft animals	- select the draft animals with respect to the factors	- rural population
		- disposability - care capacity	- projects in the field of animal power
		- disposing power - basis of feeding	- veterinary medical
		- costs services
	Production	- selection of a suitable craft workshop promotion projects	- craftsmen, trade
Demonstration phase	Acceptance/ economy	- examine and compare the time consumption required for the use of animal powered and motor mills	executing agency, craftsmen,
		- determine the output of the animal powered mill, compare with already tested animal powered mills	women, rural population, projects in the field of food technology
		- examine and point out the economy and easy maintenance of the animal powered mill in comparison with the motor mill in the respective context
		- evaluate the quality of the flour produced by t raditional procedures regarding
		- fineness - hardness
		- homogenity - colour
		- humidity
		- trials with the animal powered mill:
		- adjustment of the millstones
		- drying of grains
		- sieving of flour
		- evaluate the test results, identify deficiencies
		and problems in the field of technology and
		organisation of work; if necessary, technical and organisatorial alterations.
		- perform demonstrations for the rural population
		- food test with consumers, until a satisfactory flour quality is reached
	Organisation of the use of the animal powered mill	- examine in how far women's groups already exist, which organisation structures they have	women, rural population,
		- judge the dynamics and readiness for innovations	executing agency, women's projects
	Production trade promotion projects	- craftsman training “on the job"	executing agency, craftsmen,
	Preparation of the pilot programme	- selection of suitable villages for a pilot programme	executing agency, rural population, rural development projects
Pilot programme.	Executing agency	- selection and training of counseling staff village counselor, women's	executing agency, craftsmen,
		- work and organisation scheme for the counseling activities	projects, trade promotion
		- responsibilities	projects, projects in the field
		- investigations to be performed	of food technology
		- time schedule
		- reporting
	Draft animals	- training of the future mill users in handling the draft animals	executing agency, women, village counselor, rural population, projects in the field of “animal power", veterinary medical services
		- counseling with regard to feeding of and care for the animals, training of care staff
	Organisation of the mill use	- find out the responsibilities within the group	executing agency, rural women's groups, village counselor
		- overall responsibility
		- organisation of the fund
		- maintenance of the power gear
		- if necessary, care for the draft animals
		- determine the organisation of the mill use
		- which draft animals are used?
		- who may grind when?
	Acceptance/ economy	- evaluate the quality of the flour produced by traditional procedures regarding	executing agency, women, village counselor, craftsmen, projects in the field of food technology
		- fineness - hardness
		- homogenity - colour
		- humidity
		- trials with the animal powered mill:
		- adjustment of the millstones
		- drying of grains
		- sieving of flour
		- examine and compare the time consumption required for the use of animal powered and motor mills
	Production/ maintenance	- continuous counseling and assistance for the craftsman	executing agency, craftsman, trade promotion projects
		- training of maintenance staff in the village

3. Comparison of the economic efficiency of animal-powered mills and motor mills (100 FCFA <= 0.33 $ US)

	Animal powered mill (25 families).		Motor mill	(50 families)	(100 families)	(200 families)
1. General data	pilot lot	improved model	(25 families)
1.1 Investment costs ($US)1
- mill	1547	829	4144	4144	4144	4144
- building	-	-	829	829	829	829
1.2 Working hours (h/d) 8	8	1	2	4	8
	(d/a) 300	300	300	300	300	300
	(h/a) 2400	2400	300	600	1200	2400
1.3 Output (kg/h)²	12	12	100	100	100	100
Output (kg/d)	96	96	100	200	400	800
Output (kg/a)	28 800	28 800	30 000	60 000	120 000	240 000
1.4 Fuel/oil ($US/h)3	-	-	1.16	1.16	1.16	1.16
1.5 Useful life (h)4	24000	24000	4500	5600	7700	12000
Write off time (a)	10	10	15	9.3	9.4	5
2. Annual costs
2.1 Writeoffs ($US/a)5 155	83	359	528	730	912
2.2 Donkey food ($US/a)6 124	124	_	_	_	_
2.3 Staff costs ($US/a)7 (animal power: animal care; motor mill: miller)	193	193	155	310	622	1243
2.4 Maintenance and repair8 ($US/a)	183	183	238	431	818	1440
2.5 Fuel/oil ($US/a)	_	_	348	696	1 392	2 784
3. Grinding costs ($US/a)	655	583	1 100	1965	3562	6379
Grinding costs ($US/kg)	0.023	0.02	0.037	0.033	0.03	0.027

¹ Diouf, D. et al. (Senegal): The investment costs of a motor mill are assumed to be 1285000 FCFA
(motor Hatz, 11 H.P:and hammer mill Skiold).
M.D.R. (Burkina Faso): The investment costs are assumed to be 1 200 000 FCFA (motor
Anil, 8 H.P. and disk mill Hunt)
Altarelli-Herzog, V. (Burkina Faso): The investment costs for the same mill are claimed to be
636 500 FCFA, the investment costs for the mill building 60 000 FCFA (written off for 10 years).
According to our own experience, these figures are obviously too low. For the cost comparison the following values were assumed:
Mill and motor: 1 200 000 FCFA
Building: 240 000 FCFA

² Diouf, D. et al. (Senegal): The theoretical grinding output of the mill is 300 kg/h. However, this value was not achieved in practice. The following actual grinding times (incl. idle time) are assumed:
small villages: 100 kg/4 h
large villages: 250 kg/4 h
paid grinding: 400 kg/8 h
M.D.R. (Burkina Faso): Grinding output 100 kg/h. The assumption of 100 kg/in was taken over for the cost comparison.

3 Diouf, D. et al. (Senegal):	Fuel consumption	in small villages: 1 1/60 kg
		in large villages: 1 1/80 kg
		paid grinding: I 1/50 kg
Fuel price:	155 FCFA/I
Oil consumption	in small villages: 0.1 1/100 kg
		in large villages: 0.041/100 kg
		paid grinding: 0.1 1/100 kg
	Oil price: 860 FCFA/l

M.D.R. (Burkina Faso):	Fuel consumption: 21/h
	Fuel price: 250 FCFA/l
	Oil consumption: 0.16 l/h
	Oil price: 600 FCFA/l

Altarelli-Herzog (Burkina Faso):	Fuel consumption: 0.77l/h - 1 l/h
	Fuel price: 252 FCFA/l
	Oil consumption: 17 - 35 FCFA/h
	For the cost comparison the following values are assumed:
	Oil consumption: 0.05l/h at 700 FCFA/l

⁴ Diouf, D. et al. (Senegal): The write-off time for the motor mill is assumed to be alternatively
15 or 5 years.
M.D.R. (Burkina Faso): A 5-year write-off time is assumed for the motor mill.
Altarelli-Herzog, V. (Burkina Faso): The write-off of the motor mill is assumed to be 4 years, of the building over 10 years.
For the cost comparison the useful life of the motor mill was assumed to be 12 000 h when fully utilized (8-hour operation), which corresponds to 5 years. For l-hour operation, the useful life was assumed to be only 4500 h (corresponds to 15 years). The other values were straight-line interpolated.
Since the animal-powered mill has only very few components which cannot be produced locally, and the grinding unit runs only with one sixth of the number of revolutions for which it was designed when motor-driven, a useful life of 24 000 h was assumed (corresponds to 10 years).

⁵ without interest

⁶ When feeding additionally 50 kg peanut shells, maize etc./month during 6 months/year. 50 kg a 6000 FCFA

⁷ Diouf, D. et al. (Senegal): small village: 5 000 FCFA/month large village: 12 500
FCFA/month paid grinding: 10 000 FCFA/month M.D.R. (Burkina Faso): 10 % of the grinding price of 15 FCFA/kg corresponds to 1.5 FCFA/kg. Altarelli-Herzog, V. (Burkina Faso): same as MDR

4. List of the studies, reports an brochures elaborated within the framework of the project

Information booklets
Peter Lowe: Der Gopel - eine Alternative bei der Mechanisierung der Landwirtschaft (Animal-powered systems) Eschborn 1983 German, English, French

Projekt-Consult: Gopeltechnologie - ein Programm von GATE/GTZ in Westafrika (Animal power gears - a programme of GATE/GTZ in West Africa) Frankfurt 1986, German, English

Technical reports - not country-specific

Status reports:

Bernard Gay: Moulins et Maneges (Mills and power gears), Verberie, 1984, French
Jacques Sarda: Pompes et Maneges (Pumps and power gears), Verberie, 1984, French
Wulf Boie: Reibradgopel und Kettengopel (Power gears with friction wheels and chains)?
Frankfurt, 1984, German

Wulf Boie: Industriell gefertigte Antriebselemente fur Gopelwerke (Industrially manufactured driving elements for power gears), Frankfurt 1984, German

Short reports, test reports:

Jacques Sarda: Construction d'un prototype de moulin de fabrication artisanale (Development of a cereal mill for artisan manufacturing), Verberie, 1985, French

Wulf Boie: Anpassung einer Pumpe an den Universalgopel - Testbericht (Adaptation of a pump to the universal power gear - test report), Frankfurt 1985, German

Wulf Boie: Anpassung von Reisschalmaschinen an den Universalgopel - Testbericht (Adaptation of rice husking machines to the universal power gear - test report), Frankfurt 1985, German

Wulf Boie: Marktubersicht und Beurteilung industriell hergestellter Gopel (Market survey and evaluation of industrially manufactured power gears), Frankfurt 1986, German

Peter Lowe: Technischer Kurzbericht industrieller Universalgopel (Short technical report of industrial universal power gears), Frankfurt 1984, German

Country-specific studies

Senegal:

Peter Lowe: Moglichkeiten der Erprobung und des Einsatzes von Hirsemahlen mit Gope lantrieb im Senegal (Possibilities for testing and using millet mills with power gears in Senegal), Frankfurt 1984, German

Nicolas Bricas/ Rapport d'Evaluation du projet manege au Senegal (Evaluation report of the

Francois Protte: power gear project in Senegal), Dakkar 1986, French

Burkina Faso:

Peter Lowe: Prefeasibility-Studie, Test und Demonstration von Gopeln in Burkina Faso (Prefeasibility study, test and demonstration of power gears in Burkina Faso), Frankfurt 1985, German

Ursula Fitzau: Choix de zones et de sites d'experimentation de manege a traction animale au Burkina Faso (Selection of test regions and locations for animal-powered systems in Burkina Faso), Frankfurt 1985, French

Barry Hassan/ Introduction des Moulins a Traction Animale au Burkina Faso, Rapport Final

Peter Lowe:

de la Phase de Demonstration (Introduction of animal-powered mills in Burkina Faso, Final report of the demonstration phase), Frankfurt 1987, French

Sarda, Jacques: Projet Manege au Burkina Faso (Power gear project in Burkina Faso), Verberie 1986, French

Sierra Leone:

Winfried Muziol: Prefeasibility-Studie: Einsatzmoglichkeiten von Gopeln in Sierra Leone (Prefeasibility study: Employment possibilities of power gears in Sierra Leone), Frankfurt 1985, German

Wulf Boie: Bau von 2 Demonstrationsgopeln im Rolako Equipment Centre des "Sierra Leone Work Oxen Project" (Construction of 2 demonstration power gears in the Rolako Equipment Centre of the "Sierra Leone Work Oxen Project"), Frankfurt 1986, German

Central African Republic:

Peter Lowe/ Prefeasibility-Studie, Einfuhrung von Gopelmuhlen im GTZ-Projekt "ACAD
Ursula Fitzau: OP" (Zentralafrikanische Republik) (Prefeasibility study, Introduction of animal-powered mills in the GTZ project "ACADOP" (Central African Republic)), Frankfurt 1986, German

Walter Wilmers: Fabrication et installation de deux moulins a manege au nord de la RCA (Production and installation of two mills with power gears in the north of the CAR), Frankfurt 1986, French

Mali:

Werner Roos: Prefeasibility-Studie uber die Einfuhrung der Gbpeltechnologie in Mali (Prefea sibility study for the introduction of animal-powered systems in Mali), Frankfurt 1985, German

Mauretania:

Bernard Gay: Introduction de maneges en Mauritanie (Introduction of power gears in Mauretania), Verberie 1985, French

Togo:

Peter Munzinger: Kurzbericht: Moglichkeiten der Erprobung und des Einsatzes von Gopeln in Togo (Possibilities for testing and using power gears in Togo), Frankfurt 1985, German

Non-country-specific studies

Ursula Fitzau: Berucksichtigung soziokultureller Faktoren bei der Einfuhrung van Gopelmuhlen in Westafrika (Accounting for socio-cultural factors when introducing animal- powered mills in West Africa), Frankfurt 1985, German

Studies and reports, which were conducted on behalf of GATE before the beginning of the power gear project

Peter Lowe/	Gopelschopfwerke in Agypten (Animal-powered water raising systems in
Wulf Boie:	Egypt), Frankfurt 1983, German
Peter Lowe:	Die Senia - eine technische Innovation im Tal des Beni Boufrah (Marokko)
	(The Senia - a technical innovation in the valley of Beni Boufrah (Morocco)),
	Frankfurt 1983, German

Diploma theses

Wulf Boie: Stand der Technik auf dem Gebiet der Gopeltechnik sowie Konstruktion und Bau eines Prototypen fur die Anwendung in Entwicklungslandern (State of technology in the field of power gears as well as construction and building of a prototype to be used in developing countries), Cologne 1982, German

Ursula Fitzau: Auswirkungen technischer Innovationsprozesse auf die Lebenssituation von Frauen in Entwicklungslandern am Beispiel der Einfuhrung von Gopelmohlen in Burkina Faso (Consequences of technical innovation processes for the situation of women in developing countries, exemplified by the introduction of animal-powered mills in Burkina Faso), Frankfurt 1987, German

5. Source documentation of figures

Part 1

Lowe, Peter (Projekt-Consult) (Cover photograph, 1a, 2, 3, 4)
Fitzau, Ursula (Projekt-Consult) (1b, 6)

Part 2

Walther, Karl: Die landwirtschaftlichen Maschinen, Leipzig 1910: (1)
Patent Office of the German Empire: Patent Specification 20051 (2)
Patent Office of the German Empire: Patent Specification 8678 (3)
Patent Office of the German Empire: Patent Specification 46642 (5)
Stuhlmann, Franz: Ein kulturgeschichtlicher Ausflug in den Aures (4) Ohler-Grimm, Ueli (Okozentrum Langenbruck) (6) Lowe, Peter (Projekt-Consult) (7-9) Oertel, Welf (Bachelor of Design) (11, 13-38)
Figures not specified: Wulf Boie

6. Contact addresses

German Appropriate Technology Exchange (GATE)
Postfach 5180
D-6236 Eschborn I (FRO)

Projekt-Consult
Beratung in Entwicklungslandern GmbH
Limburger StraBe 28
D-6240 Konigstein (FRO)

Institut Technologique Dello
8, Rue Paul Bert
F-83300 Aubervilliers (France)