|Low Cost Charcoal Gasifiers for Rural Energy Supply (GTZ, 1994, 49 p.)|
|8. Non-technical aspects of gasifier operation in the field|
The existing gasifier programmes are addressed to two typical user configurations: The "community plant" and the "private owner plant". The basic conditions as well as the economic situation of these cases of ownership are remarkably different, and any dissemination strategy has to define exactly which is the target group.
a) The community plant
The most common application (expressed in numbers of installed gasifiers, for example within the gasifier programmes in India and Thailand) is the gasifier with engine and electric generator, installed for village electrification (most of all: light and television). Typical features are:
- The financial power of the community is too low to meet the investment costs (even with a low-cost ferrocement gasifier, the costs for engine, generator and electric grid have to be considered). The installation is highly or completely subsidized by institutions or governmental agencies. This subsidy is seen as part of a compensatory activity to improve living and working conditions in economically underdeveloped regions.
- The operational costs are the salary of the operator and fuel costs. The total of the operational costs is significantly lower than the savings for kerosene and candles, used for lighting purposes before, and the users can enjoy a limited luxury like radio and television at reduced costs (no batteries and no fees for battery charging).
- The community members contribute by "cash or in kind": Typically they pay a small amount of cash and supply a certain amount of the fuel. Due to very limited and irregular income, especially the contribution by cash is irregular. This results in decreasing motivation of the operator, who is not acknowledged adequately for his job.
- As the typical village electrification system does not contribute to an increase of monetary incomes of the community, it is not considered as a first priority asset. A general feeling is that the government, who subsidized the plant, should take care of the operation as well.
The motivation of a community to maintain a gasifier powered electricity supply is very sensitive to fluctuations of the socio-economic situation. According to Jain , the same mechanism is valid in India as observed in Colombia [3, 4]. Electricity for lighting purposes is a unanimous demand, if village communities are asked, but nevertheless it is not a basic need. Faced with the offer to get a subsidized gasification plant, the communities take their chance to get electrification without major financial participation. Seeing this probably unique chance, they agree to take over the operational costs, e.g. the salary of the operator and the costs for fuel preparation. But, if for any reason the financial situation gets worse, the financial contribution for electric light is the first expenditure to be saved, and participation by fuel or labour does not help the operator in his specific situation.
In all reported situations in India, Thailand and Colombia where community electrification was installed by means of a gasifier and where the operation costs were left to the users, problems are reported due to irregular paying of the fees. Internal conflicts of this kind often result in idle periods of the plant and in a change of the responsible operator, when he is not longer willing to do this job. The new operator is less qualified, and further problems in operation and maintenance are to be expected.
A community installation which was fully subsidized and maintained by an institution (Jain), with the users paying only a small symbolic fee, was successful. This indicates again that not technical problems, but user behaviour is the source of trouble.
In the two community installations in Thailand, described as case studies by Naksitte , the participation of the users does not seem to present major problems. The villagers contribute with charcoal as well as with electricity fees. But the positive results in Thailand are perhaps due to the fact that these installations have been installed a few month before the evaluation. During the gasifier project in Colombia, it could be observed that in the first year after installation everything is organized very well, but then, gradually, the conflict begins. These conflicts could be solved, when external advice and technical assistance by regular visits of authorities were available.
Communal electricity supply is obviously an especially difficult application, and it will not develop just by offer and demand of gasifier plants. The typical low-income-community, living mainly by subsistence agriculture, has no real chance to decide which energy plant is the most economic solution for it. The village cannot afford any energy plant. If a governmental agency wants to help this underprivileged part of the population, gasifiers can be the best solution: They are much cheaper than the connection to the public electric grid, and after the installation the system is autonomous in its fuel supply. The hardware costs of the gasifier plants with 3-10 kW electric power output are not a relevant factor for a governmental programm. It is not really a crucial question whether the specific installation costs are US $ 200.-or $ 500.-per installed kW. What makes a dissemination programme of that kind expensive are the salaries of the engaged governmental employees, the travel expenses and the organizational infrastructure.
If serious programmes for development of underprivileged regions exist, much more than energy supply is necessary. If such a programme deals with improvement of agriculture, production of marketable goods, reforestation, communal organization - than it seems to be logical to include the appropriate energy supply, and this can mean gasifiers. In that case, a concentration of gasifiers in "clusters" of approximately 10 villages makes sense. This makes the efficient organization of the fuel supply (commercialisation of charcoal production for the gasifiers) as well as the technical back up much easier.
Even if the installation costs are not the crucial point in that situation, the ferrocement-gasifer appears to be advantageous. If the users participate in the construction, or if a local group specializes in building ferrocement gasifiers, the plants would not be a "gift" from the government. It is very probable that this results in an increase of motivation to maintain the plant, apart from the advantage that any repair of the plant is easy and that the technology of building containers and pipes in cement can be very useful for other applications.
b) The private owner plant
The gasifier run by a private owner or an institution is up to now not so numerous as the community plant, but the percentage of success seems to be much higher, as soon as there is a real economic advantage. According to the case studies in India and Thailand, the typical features are:
- The gasifiers are seen as ´´demonstration units" and installed by scientific institutions, involved in gasification research. The investment costs are subsidized. The owner does not belong to the poorest of the poor: He would be able to finance a plant on its own, but he is not sure yet that a gasifier is technically reliable enough, and that the savings in fuel costs are significant.
- It is easier for the private owner to assess the economical advantage of the gasifier. The more operational hours per year, the higher the savings in fuel costs compared to liquid fuel operation. If only light in the evening is supplied, this is not so interesting in terms of financial benefits, but it may be done as a sort of interesting experiment. If agricultural or other commercial activities are combined with the energy use (irrigation water pumping, flour mill, etc.), the gasifier becomes economically interesting.
- The private owner has a particular interest in the successful operation of the plant, he is usually more qualified than a communal operator and more flexible when repair- or maintenance problems come up. He is really testing the gasifier to see whether it is useful to save money or to give a reliable energy supply. The private owner loses interest, if the technology appears not to be reliable and needs too much care.
Generally, the motivation is much better, if a private owner (or, even better, an owner/ operator) is running the plant. In the examples reported by Jain, the use of private pump sets and electricity supply by small (3.5-7.5 kW) gasifiers was successful, if the location was remote from the electric grid, or when the electric grid was considered as unreliable. Two examples for heat application (institutional cooking) in India show positive results. An installation, run by a well organized institution to supply energy (cooking gas or electricity) to the training centers and the canteen, is more or less equivalent to ´'private ownership": The responsibilities are clear, the salaries of the employees as well, and economic advantages by reduced fuel costs are easy to monitor. It must not be overlooked, however, that CO2 is a poisonous gas, requiring careful handling of the stove.
In the case of the private owner, the investment costs are extremely important. The ferrocement concept can reduce these costs considerably. It is, however, not probable that the typical private owner will have the time and interest to build the gasifier himself. In the majority of cases he considers himself as an entrepreneur whose activities do not allow to spend three weeks in building a gasifier. In that case, a gasifier manufacturer must be able to build the plant on the location, either completely or by using prefabricated components. The typical manufacturer would not be a metal work-shop, but a firm which deals with construction elements and plastering. Such commercial manufacturers of cement gasifiers do not yet exist, and the realistic product costs are not yet verified. First estimations are lined out in chapter 9 of this report.
Of course, a gasifier means always some additional costs compared to the mere combustion engine, and it is important to keep in mind that these additional costs are not only hardware costs but increased labour costs for operation as welt But, if the gasifier is reliable enough-that means that costs and efforts for maintenance and repair are not dominated by the subsystem gasifier, but by the rest of the technical equipment (engine, additional equipment like generator, waterpump, mill etc.) -than it is just an exercise in economic calculation to assess if a gasifier is viable or not. In that case, the dissemination of the gasifier technology can be left to the market situation and depends on the specific fuel costs and the operational hours per year. Pumps sets for irrigation water, flour mills, small machinery in cottage industries are the typical applications. Institutional cooking is an interesting (but dangerous) application. Electric lighting will be more an additional use of an existing plant, but not the driving force to install a gasifier.