Foreword
Biogas plants have become something of a permanent fixture in
Technical Cooperation between the Federal Republic of Germany and partners in
developing countries. Dating back to 1977, the first such projects were
incorporated into cooperative efforts with Indian and Ethiopian organizations.
At about the same time, the first GTZ project dealing solely with the transfer
of biogas technology and the construction of biogas plants was launched in
Cameroon.
In the meantime, GTZ has assisted in building and commissioning
several hundred biogas plants in Asia, Africa, South and Central America. While
most of the systems, in question are on a small scale intended to supply family
farms with energy and organic fertilizer, some large-scale systems with the
capacity to generate more than 100 m³ of biogas daily have been installed
on large stock farms and agroindustrial estates.
In general, biogas technology is for rural areas. In addition to
generating energy, biogas systems help stimulate ecologically beneficial
closed-loop systems in the agricultural sector while serving to improve soil
quality and promote progress in animal husbandry. Consequently, the promotion of
biogas technology is regarded as an integral part of technical cooperation in
rural areas and, hence, as a key sector of development cooperation on the part
of the Federal Republic of Germany.
Within the GTZ, biogas activities center on
- the Biogas Extension Program (GATE), with interdisciplinary
teams of extension officers presently working in four different countries:
- the Special Energy Program (Mineral and Energy Resources
Division), with rural energy-supply projects now ongoing in ten countries, and
- projects engaged in by Division 14(animal production, animal
health and fisheries), within which the importance of biogas technology as a
flanking measure in animal husbandry is steadily increasing.
By concentrating the engineering and operational experience gained
in numerous biogas projects, this handbook is intended to serve project
practicians and advisors as a valuable practical guideline with regard to
technical, agricultural and socioeconomic aspects.
Deutsche Gesellachaft fur Technische
Zusammenarbeit (GTZ) GmbH
Authors' Foreword
Biogas plants constitute a widely disseminated branch of
technology that came into use more than 30 years ago in Third World countries.
There are hundreds of thousands of simple biogas plants now in operation, and
each one of them helps improve the living and working conditions of people in
rural areas.
While this guide deals only with biogas systems of simple design,
the technology is nonetheless sufficiently complex and rewarding to warrant
one's close attention to its proper application, planning and construction. The
only good biogas system is a well-planned, carefully executed and properly
functioning one that fulfills its purpose.
This guide addresses the planners and providers of stock-farming
and agricultural-extension services in developing countries. It is intended to
serve as:
- a source of information on the potentials of and prerequisites
for biogas technology,
- a decision-making and planning aid for the
construction and dissemination of biogas plants
- a book of reference for
information on practical experience and detailed data.
While consulting experts, extension officers and advisors with
little experience in biogas technology will find this guideline useful as an
initial source of information, biogas practicians can use it as a hands-on
manual. The tables and engineering drawings contained herein provide standard
values for practical application. They were compiled from numerous extraneous
and proprietary works of reference and then modified as necessary for practical
use. The informational content draws chiefly on the latest know-how and
experience of numerous associates involved in the various biogas projects of the
GTZ Special Energy Program and the GATE/GTZ Biogas Extension Program, of L.
Sasse and a great many Third World colleagues and, last but not least, OEKOTOP's
own project experience.
We would like to take this opportunity to thank all of our
colleagues for their cooperation and the constructive criticism that attended
the writing of this handbook. Our appreciation also to GATE and the GTZ division
Animal Production, Animal Health and Fisheries, who made this guideline
possible. Special thanks also to Klaus von Mitzlaff for the section on
gas-driven engines and to Uta Borges for her special elaboration of the aspects
economic evaluation, social acceptance and dissemination.
We wish every success to all users of this guide. Feedback in the
form of suggestions and criticism is gratefully welcomed.
The OEKOTOP
Authors
