Application of Biomass Energy Technologies (HABITAT, 1993, 168 p.): VI. CONVERSION OF BIOMASS INTO ELECTRICITY: H. Mali

Application of Biomass Energy Technologies (HABITAT, 1993, 168 p.)

(introduction...)

FOREWORD

INTRODUCTION

(introduction...)

A. The need for modernization

B. Experience from case studies

I. WOODFUEL PRODUCTION TECHNOLOGIES

A. Introduction

B. Botswana

C. Lesotho

D. Malawi

E. Mozambique

F. Swaziland

G. United Republic of Tanzania

H. Zambia

I. Zimbabwe

J. Analysis of the case studies

K. Conclusions

II. IMPROVED CHARCOAL PRODUCTION

A. Introduction

B. The Malawi Charcoal Project

C. Charcoal markets

D. Constraints

E. Policy environment and role of the Government

F. Role of entrepreneurs and informal-sector artisans

G. Local research initiatives and indigenous technical skills

H. Role of non-governmental organizations

I. Role of end-users

J. External financial support and local credit and banking institutions

III. FUEL-EFFICIENT COOKSTOVES

A. The KCJ Project

B. Traditional cookstoves

C. Development of the KCJ - the institutions

D. Constraints

E. Policy environment and role of the Government

F. Role of private entrepreneurs and informal-sector artisans

G. Local research initiatives and indigenous technical skills

H. Role of non-governmental organizations

I. Role of the end-users

J. External financial support and local credit and banking institutions

K. Conclusions

IV. CONVERSION OF BIOMASS INTO ETHANOL

A. Introduction

B. Brazil

C. Zimbabwe

D. Malawi

E. Kenya

F. Thailand

V. BIOGAS

A. Introduction

B. India

C. China

VI. CONVERSION OF BIOMASS INTO ELECTRICITY

A. Gasification

B. Pura village, India

C. Hosahalli village, India

D. Mauritius

E. The Philippines

F. The South Pacific

G. Indonesia

H. Mali

I. Brazil - potential

VII. PERCEIVED PROBLEMS, SOLUTIONS AND POLICY OPTIONS

(introduction...)

A. Environmental impacts

B. Food or fuel?

C. Land availability

D. Raw-material supply

E. R&D and technology transfer

F. Social factors

G. Economics

H. Policy

I. Institutions

VIII. CONCLUSION

REFERENCES

H. Mali

Chinese-built rice-husk gasifier power plants (160 kWh) were installed in the early 1970s, according to Mahin (1989), at two rice mills at Dogofiri and N'Debougou. These have operated successfully since then with more than 55,000 hours operating experience, although economic analyses of these plants are not easily available. In 1986, with the assistance of GTZ (German Agency for Technical Cooperation), an additional Chinese-built gasifier was installed nearby at the rice mill in Molodo which processes about 20,000 t/yr of rice. The plant produces about 1 kWh for each 2.5 kg of rice husks used in the gasifier. It generates up to 160 kW of power. The total annual operating costs were DM146,877 (or DM0.26/kWh) which is 54 per cent of that of a diesel- engine plant. The GTZ study (Mahin, 1989) indicates the difference in capital cost between the diesel and the gasifier plant. Investment costs of the gasifier power plant could be recovered in less than four years. Table 16 provides a summary of cost of the rice husk-fulled gasifier power plant at Molodo.

Table 15. Gasification of rice husks, Indonesia

Parameters		Gasifier I		Gasifier II
(a) Typical daily operation data
Operating time		18.00-24.00		18.00-24.00
				04.00-06.00
Electricity generated (kVA)(kW)		12(9.6)		18(15)
Diesel fuel consumption (I/day):
	100 per cent diesel fuel	40		42
	dual-fuel operation	12.0		12.6
Lubricant oil consumption		81/60 hr		81/20 hr
Rice husk consumption (kg/hr)		23.3		30.0
Temperature of outlet gas (K)		673		603
Temperature or gas entering the engine (K)		303		308
Lower heating value of gas (kJ/m³)		not measured		4,300
Filter cleaning		once in 2 weeks		once in 2 weeks
Tar in gas at gasifier outlet (g/m³)		1.7		3.8
Tar in gas after dry filter (g/m³)		0.37		1.00
(b) Parameters relevant to economic analysis
Diesel oil replacement (percentage)		70		70
Rice husk to electricity energy conversion factor (kg/kWh)		2.4		2.0
Lubricating oil cost (Rp/dm³)		900		2,500
Rice husk price (Rp/kg)		7.5		7.5
Electricity delivered price (Rp/10 W/month)		2,000		1,000
Transmitted electrical power (kW) Diesel oil price (on site) (Rp/dm³)		4.5 250		5.0 250
Operator salary (Rp/month)		30,000		25,000
(c) Economics of generating electricity using dual-fuel and full diesel
		Dual-fuel		Full-diesel
		Rupiahs	Percentage	Rupiahs	Percentage
Investment:
	Gasifier	5 000 000	27		0
	Diesel engine	13 000 000	70	13 000 000	96
	Building	500000	3	500 000	4
	Installation	200000	1		0
	Total	8700000	100	13 500 000	100
Operating costs:
	Labour	306 000	7	180000	4
	Maintenance	639 840	14	336 960	7
	Rice husk	583 200	13		0
	Diesel oil	1 010 880	22	3 369 600	66
	Sub-total	2 539 920		3 886 560
Depreciation		1 962 500	44	1 187 500	23
	Total expense	4 502 420	100	5 074 060	100
Production cost (Rp/kWh consum.)		347		392
Production cost (Rp/kWh gen)		116		131
Sales income (Rp)		5 404 320		5 404 320
Cash flow (Rp)		2 864 400		1 517 760
Economic variables:
Gasfier lifetime (years)		8		8
Engine lifetime (years)		12		12
Building lifetime (years)		8		8
Daily operating hours (hr/day)		8		8
Annual operating hours (hours)		2 592		2 592
Load level (kW)		15		15
Diesel consumption (1/hr)		2		5
Husk consumption (kg/hr)		30		33
Registered load (kW)		5		5
Electricity consumed (kWh/yr)		12 960		12960
Electricity generated (kWh/yr)		38 880		38 880
Diesel price (Rp/l)		250		250
Husk price (Rp/kg)		8		-
Operator wage (Rp/hr)		63		63
Labour wage (Rp/hr)		44		44
Load factor		1		1
Electricity price (Rp/kWh)		417		417
Interest (percentage)		12		12

Notes: $US1=Rp 1750
Capital cost for a gasifier of 15 HP is $US 3000; the price of higher capacities is calculated by:
Capital cost (× HP) = Capital costs (15HP) * (x/15) (10×0.3)
Interest rate is 12 per cent per annum
Gasifier economic life is 7 years
Engine derating due to oil replacement is proportional to the percentage of oil replacement
Mechanical power to run a rice meal is 27 kW per ton of rice milled per hour 250 kg husk is produced per ton of rice, of which only 25 per cent is needed to power the mill
Source: Manning and Beenackrs, 1990.