|GATE - 2/85 - Health, Water and Sanitation (GTZ GATE, 1985, 56 p.)|
2nd International Producer Gas Workshop Was a
by Albrecht Kaupp
The 2nd international conference of the Producer Gas Round Table which recently took place in Indonesia was jointly sponsored by the members of the Producer Gas Round Table (PGRT), of which GATE is a member, and organized by the Beijer Institute and the Institute of Technology in Bandung, Indonesia. The conference was preceeded by a workshop which covered all theoretical and practical aspects of producer gas technology. The participants of this course were mostly engineers from Third World countries who had the opportunity to work with four gasifiers and learn more about the practical aspects of the technology as well as its theory.
For seven days, four teachers lectured on subjects such as the theory of gasification, engine modification for producer gas operation, gas cleaning, economics and safety aspects. In addition many measurements were taken during the operation of various gasifiers with different fuels, and the gasifier performance evaluated. The workshop was well organized and received, although the complexity of the subject and lack of time made it necessary to rush through some of the topics. It is worth mentioning that, despite the high costs for donor agencies to cover all expenses for the course, it seemed to be the most effective way to impart a fair picture of the present state of the art to 23 participants from 15 countries.
Following the workshop, the conference on producer gas technologies was attended by about 125 participants from 38 countries. Due to his own long involvment in the research and promotion of producer gas technologies the writer found the information given at the conference rather disappointing, although many of the well-known experts in the field participated and the organizers made great efforts to emphasize field experiences of the technology. The results, highlights, controversies and conclusions are summarized for the benefit of the reader.
Almost everything was old hat
The interest of manufacturers of gas producer engine systems to present information about their equipment at the conference was disappointing. Particularly if one takes into consideration that many representatives of major donor agencies which support gasification technologies were present.
By far the largest number of lectures concentrated on reporting already known facts about gas producer engine systems. An exception was the lecture and demonstration of a small open-core downdraft gasifier for rice hulls and a contribution from India about producer gas in internal combustion engines which were both enlightening and very well researched.
Gasification technology has certainly not reached any widespread
acceptance and made only marginal headway concerning the reliability and
flexibility of a gasifier engine system. Much information about new reactor
designs was not presented with the exception of more detailed explanations about
the theory of open-core (stratified) downdraft gasifiers which seem to deserve
more attention, although they have been around for decades and are used for rice
hulls successfully. Otherwise the information given concentrated on the known
updraft and downdraft gas producers with no reference to fluidized-bed and two
stage gas producers.
Gasification technology succesful in Brazil
The PGRT had invited representatives from three countries (Brazil, India, the Philippines) where it is believed that a national programme to introduce gas producer engine systems exists. The talk of the representative from Brazil was of great interest, since gasification technology in Brazil seems to be widespread and successful. It was reported that over 1600 units are in operation as heat or automotive gasifiers as well as for stationary power generation. This programme can be viewed as the only one which succeeds with the help of private business and does not depend on government support or international donor agencies. The gasification programme in the Philippines which has been well publicised and advertised for years now, seems to have difficulties of the following nature: a lack of knowledge and understanding on the part of the users of the systems; sharply increased charcoal prices which make the operation of a small charcoal gas producer engine system uneconomical; the lack of interest of private business to built gasifiers; a badly designed gas cleaning train and lack of a product improvement programme for the "government gas producer". Two representatives from India talked about efforts to promote gasification technology and first results were presented in the form of small conventional downdraft gas producers.
There seems to be a tendency on the part of some of the manufacturers in industrialized countries to built larger and larger units in the hope of improving the economical advantage of the systems compared with fossil-fuel power plants. Such plans contradicted the opinion of most representatives of the Third World that the largest number of applications is in the small power range from 2-200 kW (el) and that logistic problems to supply the plant with enough biomass are to be expected, with large units.
Only one engine manufacturer showed real interest in gasification technology and presented accurate and interesting data on the performance of dual-fuelled diesel engines on producer gas. The discussion on engines was determined by the following trends and observations:
- The operation of dual-fuelled diesel engines with producer gas results in practice in much lower diesel oil savings than usually stated and cannot be considered economical in many cases.
- The conversion of a diesel engine into a true gas engine is not possible with some diesel engines and in any case results in extraordinarily expensive gas engines.
- There is a general lack of low-speed engines which are considered more appropriate for producer gas.
- Today's engines are high-performance engines and require a very pure gas which is difficult to obtain with the present gas-cleaning trains.
International Conference Cooperation in Information and Documentation in the Field of Appropriate Technology
The German Foundation for International Development (DSE) and GATE are preparing a conference which will try to clarify and discuss the role of technological information in the context of Technical Cooperation.
Since all GATE cooperation partners are invited the meeting will at the same time reflect and critically evaluate GATEs particular concept of cooperation with non governmental groups in developing countries.
The conference will take place in Berlin (West) ,Sept. 9-13, 1985.
Lack of standards
There was an astonishing lack of opinions and information about the effectiveness of gas-cleaning trains, and most of the participants also admitted that malfunctioning of the systems is mainly caused by dirty gas reaching the engine. In fact the subject of gas cleaning and standards of how pure the gas should be for internal combustion engines receives too little attention. It should be remembered that such standards existed during the heyday of gasification but are no longer applied. There is also a lack of widely accepted methods to measure the dust and tar content of producer gas, which is not so easy. In addition no agreement on what species should be measured and how they should be labeled has been reached.
The reports about gasifiers which are able to gasify agricultural residues were as disappointing as previous reports on this subject over the last five years. There is absolutely no sign that gasifiers for this type of biomass are available. The results presented were as vague as usual. The writer got the impression that all the information presented on so called succesful gasification of biomass such as cotton stalks, bagasse, sawdust, coffee and ground nut shells as well as coconut husks is based on short term experimental runs and does not represent commercial operations. The experience in the gasification of biomass which is different from wood is therefore founded on very few operational hours and perhaps a few tons of biomass. Exceptions are a few commercial installations for rice husks and coconut husks which seem to have been in operation for between 12,000 and 70,000 hours.
The gasifier monitoring programme of the World Bank was presented. Its objective is to gain more inside knowledge and data about existing commercial installations. This programme should be most welcome because it can be an important tool to judge the rumours and missinformation about existing installations and will hopefully also lead to the establishement of standards and measurement techniques.
Production is the weak link
Disagreement existed about the ability of Third World countries to manufacture gas producer systems. It is widely accepted that the economics of gas producer engines would greatly improve if they were manufactured in Third World countries. One convincing example is Brazil, which has manufactured many more gas producer engine systems during the last twenty years than all European or North American manufacturers put together. In addition these gasifiers are fairly inexpensive compared to the makes of more industrialized nations. One serious handicap for European gas producer engine systems seems to be the costs which range from $ 750 to 1500 per installed kW (el) for a complete system. On the other hand many reports on so-called well-functioning, inexpensive gas producers manufactured in Third World countries turned out to be false and misleading. One may claim that manufacturers in industrialized countries tend to automate their units too much and have been trying to develop gasifiers which are able to gasify agricultural residues without much success, while simple inexpensive gasifier systems manufactured in developing countries are only able to gasify high quality charcoal but are in many instances advertised for all kinds of biomass fuels as well.
A debate developed over the questions of whether a market existed for gas producer engine systems. In generel one can say that due to high expectations and promises about the flexibility of gas producer engine systems an artifical demand has been created. However, the market concentrates in many countries on the gasification of biomass which is different from wood and has properties which makes it highly unsuitable for the existing gasifiers. There exists therefore a high demand for gasifiers which have not yet been developed and may in many instances never be feasible or economical.
Meeting of Project Managers from Special Energy Programmes
by Rainer Geppert
In addition to an analysis of what had been accomplished to date and an exchange of information between the project managers, the staff of Department 34 at GTZ Head Office, the responsible divisional head from Division 225 of the Federal Ministry for Economic Cooperation and a representative of the Federal Ministry for Research and Technology, the purpose of the meeting was to reach basic conclusions on the perspectives for the Special Energy Programme. To this end the discussion was to cover not only the question of reformulating or adding to the original strategy, but also the possibility of extending Special Energy Programmes to 10 additional countries.
The meeting was held in Ouagadougou, the capital of Burkina Faso, the country with the longest-running Special Energy Programme (SEP) apart from Kenya. The confrontation with the urgent problems facing this country in the Sahel zone and the opportunity to convince themselves on the spot of the results already achieved in the Burkina Faso SEP enabled the participants to bring more than mere theory to bear on the questions mentioned above.
The results of the meeting were summarized in a final communique which is reproduced here in slightly abridged form.
In the first phase of the SEP the overall conditions for the use of regenerative energy sources were investigated in country programmes and individual projects. This survey covered the efficient application of technologies for making use of wind energy, water power, solar energy and biomass.
Experience to date, as presented at the meeting, shows that a number of those technologies for using renewable energy sources already implemented in the projects have already reached the stage where they have been more or less perfected technologically and offer economic benefits. Improved stoves, solar water heaters, biogas units, wind and hand pumps and small water-power plants, for example, have proved their value in local situations and over small areas. For a number of other systems we can see opportunities for further adaptation depending on local conditions. These systems include photo-voltaic systems, wind generators, biomass gasification units, solar driers, vibration grinding mills, solar plants for generating process heat.
Despite the successes achieved so far, which justify an optimistic view, all the institutions involved will have to step up their efforts if we are to ensure that a substantial proportion of the energy supplies in developing countries can be provided from renewable sources of energy.
Difficulties and problems identified
This is an important point, because it has been found during the first phase that:
· comparatively high capital cost may present an obstacle to private users of renewable energy systems,
· the rural population frequently cannot cope with the complexity of these systems,
· in many cases the users are reluctant to accept the risk associated with the technological system,
· the technologies available to date and the methods for disseminating them have not always been adapted to the needs of the target groups,
· the innovative character of the programme makes demands on the experts and institutions which have not always been adequately met in the past,
· the implementation of Renewable Energy (RE) systems in individual cases still involves a considerable amount of planning.
To this extent the participants in the Project Managers' Meeting agree with the findings of the 1981 Nairobi "Conference a New and Renewable Sources of Energy" that in this field it is essential to think on a long-term basis.
It is therefore necessary to plan and implement energy systems as part of local and regional supply strategies, in order to react selectively to energy requirements, the availability of regenerative energy sources, and specific local conditions.
In this approach, plans are to be made for the introduction of systems for using regenerative energy sources where such systems are superior to conventional systems.
It was agreed that the solving of energy problems in urban areas should also be included in future SEP activities. Here it is necessary in particular to identify and exploit the potential for energy saving in homes and in small and medium-sized industrial and craft establishments.
Continuing the SEP
The continuation of the SEP is to be based on the following aims and measures:
· The aim of the SEP is to conserve the exhaustible sources of energy in developing countries. This will make a contribution to preserving natural resources, safeguarding energy supplies, rural development and improving the energy balance and the balance of payments thus solving environmental, housing, development and employment problems.
· The results the SEP is intended to achieve are the exploitation of regenerative energy sources by means of systems which are suitable for developing countries, and the rational use of energy.
· This requires an integrated and coordinated approach involving the application, adaptation and-as far as possible- local production and propagation of RE technologies. It requires measures to promote the rational use of energy, i.e. economizing, cost-saving and substitution.
For the continuation of the programme the following requirements were formulated in the fields of technology, economics and socio-cultural integration:
· improving the reliability and ease of operation of RE systems,
· adapting the systems to local conditions,
· ensuring avaibility of spare parts and service,
· promoting local manufacturers,
· developing efficient planning methods,
· optimizing the cost/benefit ratio,
· drawing up and agreeing on economic appraisal criteria,
. propagating only those RE systems which are a viable economic proposition,
· building up consultancy know-how in the fields of economics and business management in the developing country,
· developing and pursuing marketing strategies,
· developing and introducing appropriate financing systems,
· eliminating or reducing market distortions which present obstacles to propagation measures,
· ensuring greater involvement of self-help groups and grass-roots oriented organizations in the planning and implementation of projects,
· taking better account of established structures,
· continously adapting project aims and measures to the needs of the target groups and to the changing technological and economic background conditions.
The complexity of the projects in this field demands an initial phase in which investigations are carried out into the conditions specific to the region, so that solutions which are appropriate to target groups, needs and situations can then be devised.
On the basis of these findings the SEP should be continued in the countries where it is already running.
Consideration is currently being given to investigating the possible extension of the programme to 10 additional countries.