Since the 1974 oil crisis, research and analysis on the use of biomass for energy purposes has intensified at an ever increasing rate. The deeper the investigation, the more the worldwide importance of this resource became apparent, on account of:
• the number of people whose livelihood depends to a greater or lesser extent on wood-based fuels: woodfuels are the main or only energy source for over half the world’s population;
• the wide range of end uses: not only for household cooking and heating, but also for many productive activities (artisanal, industrial) and for the services sector;
• its economic and social importance: wood entering commercial circuits creates employment and generates income at significant levels for low-income sectors of the population; wood not serving as commercial fuel satisfies the basic needs of the poorest population groups;
• the fact that wood is an environmentally sound, renewable energy resource: when properly managed, biomass resources are totally renewable and minimise the gas emissions responsible for the greenhouse effect;
• its impact on the conservation of forest resources: while it is true that the impact has in some cases been negative – where logging intensity has been higher than sustainable production, so depleting the forest resource base - there is many an instance where woodfuel use has triggered various forms of sustainable management of forest resources;
• wood is locally available: this makes it one of the most “democratic” and equitable sources of energy, in marked contrast to hydrocarbons and nuclear energy. Wood is a clean energy source and helps to mitigate the climate change brought about by excessive use of fossil fuels.
The obtaining of data, whether original or from secondary sources, constitutes the longest, most laborious and most expensive stage of studies on the consumption and provision of woodfuels. It is thus extremely important that data collection be correctly programmed so that data obtained are of adequate quality and quantity to meet the objectives of the study. If the data are accurate but insufficient, they can always be completed at a later stage. If, on the other hand, they are inaccurate (i.e. they contain important errors), it will be impossible to obtain reliable and useful results.
Considering that the process of obtaining information and data is not only expensive but also requires properly trained staff (a rare commodity in most developing countries), the present guide will provide recommendations on applying simple and fast methods to: a) verify existing data and fill the gaps; and b) build upon previous studies by means of more detailed and reliable procedures.
Although major energy sources in developing countries, woodfuels are at the same time the least understood. They are poorly recorded in national statistics, ignored by the formal economy, deprived of legal or normative framework or standards; and for the most part shunned by investment and development policy. In short, they are the ”Cinderella” of the energy, forest, rural and industrial scenarios of these countries.
It is often alleged that decision makers, politicians and even investors fail to take woodfuels into consideration because there is no exhaustive, up-to-date and realistic information base. Thus, ignorance would appear to be the reason (or excuse) for inaction on the part of government departments and private enterprises.
Unfortunately, while many countries have a certain amount of information on the production, availability and use of woodfuels at national level, this is usually fragmented, incomparable or incorrect. Many case studies provide valid information, but their application is limited to the specific locality or sector examined, and often the data cannot be compared because obtained through differing methods. Official statistics compiled from incomplete or incorrect records often conceal more than they reveal about the actual importance of this energy source.
On the other hand, non-governmental organizations and scientific and educational bodies concerned with environmental conservation, with improving the quality of life of users and producers, or otherwise involved in woodfuel matters lack the sort of information they require to guide their activities. Such institutions need simple, effective analytical methods to evaluate the actual and potential use of these fuels.
Information on woodfuels is important because it:
1. indicates the actual scale of their use;
2. helps to understand how wood-energy systems work;
3. provides a basis for evaluating the contribution of the forest sector to energy supply, job creation and income generation, and for analysing potentialities, prospects and trends;
4. helps determine the extent to which woodfuels contribute to the energy balance;
5. provides a detailed understanding of the existing situation which helps plan the wood-energy sector and devise related policies, strategies and programmes; and
6. helps identify investment projects needed to develop the sector.
Several organizations and research workers have studied the subject and produced documentation, the most notable being:
1. Diagnostico Microrregional da Oferta e Demanda de Produtos Florestais (FAO, 1990);
2. Woodfuel Surveys (FAO, 1982);
3. Guia para Levantamento do Consumo e Fluxo de Produtos Florestais ... (Zakia et al, 1992).
4. Principios Basicos de Estatística Utilizados no Levantamento do Consumo e Fluxo de Produto Florestais (Zakia, 1992);
5. Biomass Energy. Methodologies for Data Collection, Analysis and Use. FAO (Opiro et al, 2000);
6. Metodología OLADE para la Elaboración de Balances Energéticos (OLADE 1995).
The primary objective is to provide simple and flexible assistance in identifying and solving problems relating to the review, verification, collection, compilation, analysis, interpretation and presentation of data on woodfuel demand, supply and provision. Given the enormous diversity of patterns of demand, supply and provision, there is no point in proposing a step-by-step approach. The guide therefore sets out basic criteria and makes general recommendations for the collection, verification and processing of data, differentiating between:
• rapid surveys; and
• detailed surveys.
Next, it proposes a uniform methodological basis that permits comparability and consistency of findings at different scales and for different sectors of user, producer and supplier of woodfuels.
The further objective of the guide is to produce analyses of the woodfuel situation in a given sector, geographical area or country that will meet the information needs of all interested groups and identify effective and appropriate actions to: (a) optimize the performance of wood energy systems; (b) facilitate the development of sectoral planning systems; and (c) facilitate decision-making regarding woodfuel policies, strategies and programmes.
One final objective is to enable the woodfuel data collected to be used in energy planning under the Long-Range Energy Alternatives Planning (LEAP) System (Stockholm Environment Institute and Tellus Institute, 2000).
Forest services and ministries of energy often need to analyse woodfuel demand, supply and provision in order to plan the exploitation of available resources. In other cases, there is a need to understand how to manage existing forest resources better and more effectively. There may sometimes also be opportunities to invest in the sector, subject to the availability of detailed knowledge of production, marketing and consumption patterns. For all these fundamental purposes - and many others not directly relevant to this guide – there is a need for reliable information on this important sector.
The logical sequence for an analysis of woodfuel demand, supply and provision, regardless of intended scale, comprises a series of necessary stages and respective basic questions:
• what is the purpose of the study and where is it to be made?
• what will be the level of detail?
• what aspects/variables need to be verified or investigated?
• how are the data to be collected and checked?
• how are the data to be recorded and processed?
• how are the results to be presented?
• what form will the final assessment take?
The first question – “what is the purpose?” – calls for a statement of objectives in clear, concise and comprehensible terms and corresponding to the needs of all interested parties.
Needs can differ widely according to the situation and the person asking the question. Planners and decision-makers will probably be interested in finding out about the physical and economic dimensions of woodfuel use and its importance in the national energy sector, quantifying the use of forest resources for energy purposes, or assessing its role in productive activities, job creation and income generation. Users will be interested in local availability, more efficient or economic use, or price controls in the case of commercial woodfuels. Environmentalists will concentrate on the environmental impact of woodfuel use.
All these interests are valid and need to be integrated into the definition of objectives from the beginning of the study – this in order to motivate broad cooperation in data collection, to increase the usefulness of the findings and to facilitate implementation of the recommendations.
These objectives must also be reviewed at every stage of the study to ensure that decisions to be taken and activities to be initiated are compatible and coherent with the primary objectives of the study.
The question “where?” defines the geographical and sectoral scope of the study, i.e. the area concerned and the targeted groups of users, producers and traders. The answer to this question is fundamental because, on the one hand, it determines the scale of effort required and, on the other hand, it permits the extrapolation of survey findings with the desired degree of accuracy.
The “where?” is part of “what is the purpose?” and therefore needs to match the objectives. For example, if the objective is to discern the pattern of consumption and supply of a major industrial sector, the area under study must be that where that particular industry operates, and not the entire province or country.
With the survey objectives as the starting point, it will then be necessary to decide on the degree of detail required, since this will largely determine the funds needed for the exercise.
The degree of detail required is where conflict commonly arises between: (a) rapid surveys based on existing secondary information, with nationwide coverage and little detail; and (b) more time-consuming and complex surveys designed to generate primary information, with local or micro-regional coverage and a high degree of detail. Such conflict is mistaken, because:
• great detail is not necessarily associated with reduced coverage or with the generation of primary information. For example, a survey of the coffee drying sector, with nationwide coverage, can be carried out with a high degree of detail by using information from secondary sources in countries that have a Coffee Board that keeps detailed records of coffee dryers’ activities.
• A low level of detail does not necessarily mean wide geographical coverage or reliance on secondary information only. For example, a survey based on rapid rural appraisal methods applied to communities to obtain general, qualitative information on degree of penetration1, availability, and patterns of use of fuelwood will provide a preliminary, non-detailed, local description based on original data.
Summarizing, there are three factors at play: the required degree of detail; the sources of information to be used; and the geographical or sectoral coverage. The interplay of these three factors will result in different kinds of surveys. In this guide we shall be dealing with general lines to be followed for rapid and detailed surveys, irrespective of degree of coverage and sources of information.
When financial, human and time resources are scarce, rapid surveys will be the necessary choice. These will not be very detailed, irrespective of their geographic coverage. Generally speaking, it will not be possible to embark on costly field inquiries, but simplified surveys can be made, relying on qualified informants, small samples or examination of a limited number of highly significant variables such as penetration, consumption, supply patterns and other specific variables defined under the objectives.
There are often cases where all that needs to be done is to check that a given value (or group of values) is the correct value or group. In such cases a rapid appraisal is sufficient, also saving time and money.
It is possible to undertake detailed surveys when more time and other resources are available, making use of a great number of information sources and data collection tools. However, care must be taken to assess the total funds available and the costs involved.
Collection techniques geared to the chosen degree of approximation are described in Chapter 2.
Once a preliminary definition has been on objectives and scope, it is essential to review information already at hand, whether in documentary form or from qualified informants. The geographic scope of woodfuel use and stocks, characteristics of major consumers and producers, areas where availability is critical and patterns of use are just some of the aspects that need to be taken into account in such a review.
The review will also shed light on previous studies that can then be set against the objectives of the survey, thus avoiding duplication of effort and identifying information gaps that call for special attention. Particular attention will also have to be paid to the variables or aspects covered in previous studies in order to assess their relevance to explaining situations. For example, if in a survey on household fuel consumption fails to take account of the kind of stove used – and there are several types of stove – the results will not explain the differences in individual consumption levels.
It is highly important that the review be critical, with a special focus on the methodologies employed. The significance and reach of each previous study must be weighed and assessed. For example, a prior study on household fuelwood consumption based on direct measurement at a given place or within a given community will be much more useful than one based on indirect estimates or user statements, even where these are on a regional or national scale.
Once the review of secondary information is complete, it is advisable to reconsider and perhaps redefine the objectives and scope of the survey because answers to some of the questions raised at the start may have now emerged, or certain objectives chosen originally may now prove unattainable or unimportant. A true occurrence in this connection was the case of a costly field study undertaken to evaluate fuelwood consumption in the salt industry only to discover that this practice had been discontinued shortly before and that consumption was currently insignificant. Intelligence of the kind could have been acquired readily and at no additional cost from one or two qualified informants, such as salt wholesalers.
Existing information should serve to make a succinct description of the sectors and geographical areas to be surveyed. Each sector will require a characterization of general variables, i.e. those defining the actual size of the sector, its spatial distribution and changes over time. Data on general variables are largely obtained from censuses and other secondary sources, and need to be checked and supplemented by qualified informants.
Knowing the size of each sector and its geographical distribution is also essential for designing good methodology for the collection of primary data. Besides, size and geographical distribution are the attributes that define the universe to which sampling findings can be extrapolated. This subject will be dealt with in detail under “General Variables” in Chapter 2.
In addition, defining the size of a sector, its spatial distribution and its pattern of change over time is essential for using planning tools such as Long-Range Energy Alternatives Planning (LEAP) System.
One of the most important and difficult stages of the process is deciding what to measure, what to observe and what to record. It means defining the relevance of the proposed variables so that the most important can be included and those of minor significance discarded.
If the interests of the survey users have been properly represented when defining the objectives, there should be no difficulty in selecting those variables that will yield the desired information. However, it is sometimes hard to differentiate between what is important and what is secondary. A defect common to many surveys is the tendency to include more variables than needed to identify and explain the main problems or potentialities, or, worse, to include variables that will never be analysed or cannot be measured.
A case in point was a questionnaire on household fuelwood consumption in rural areas. It included questions on the age of the woman of the home and her level of education, which were very relevant, questions on small animals raised, which had little to do with fuelwood use, and one on “the efficiency of her stove”, which was not pertinent as the woman would not know how to answer.
There are any numbers of variables associated with woodfuel demand, supply and provision. These will be dealt with in Chapter 2 in terms of their relevance and usefulness and how the data can be obtained. The chapter does not set out to offer recipes but rather to provide a basis for each project to select the essential variables, in addition to others that correspond to its specific objectives.
Original data will be mostly obtained using sampling techniques. Sample design means defining sampling intensity and distribution of sampling units. Deciding on the required amount of data means applying sampling theory and pre-determining acceptable level of error. Standard data collection techniques must be used to ensure acceptable data quality, but a balance must always be sought between quality and quantity of data, in accordance with time and funding constraints. Data quality and quantity will be discussed in Chapter 3.
Data procurement, whether from original or secondary sources, is a slow, painstaking and costly stage in any study on the consumption and supply of forest-derived fuels. The work must therefore be properly planned if the resulting data are to be of desired quality and quantity. Data that are correct but limited can always be supplemented later. Data that are incorrect will never produce reliable and useful results.
Since the processes of collecting data and information are not only costly but also require properly trained staff – a scarce commodity in most developing countries – the guide recommends simple, readily applicable methods for: (a) checking existing data or filling gaps in the information chain; and (b) pursuing the study at a later stage with more detailed and reliable procedures.
In this guide, emphasis is given on techniques for collecting quantitative data, since these permit a more accurate assessment of woodfuel use and provide greater insight into related problems and potentials. This is not to disparage in any way the methods that yield qualitative data, such as the “Rapid Appraisals” or the “Participatory Appraisals” that are useful for learning people’s opinions and perceptions, or general patterns of woodfuel use, production and supply.
Chapter 2 explains the techniques and methods of data collection, as well as the necessary equipment and materials, most of which are readily available and cheap.
Data processing can be a complicated operation and, unless done carefully, can compromise the quality of the information gathered. This stage requires a revisit to the objectives in order to focus the analysis and to avoid generating a mass of tables and graphs that are largely irrelevant to these objectives.
For the purposes of this guide, it is assumed that the working group will have one or more personal computers and a basic MS Office package. Given its widespread use and ease in handling quantitative data, we suggest MS Excel for the entering, processing and analysis of data. Chapter 4 explains the recommended procedures.
Once the basic information is to hand, planning tools such as LEAP can be used. This imports/exports data from/to MS Excel and is available as a PC program.
The results must provide a precise, complete and concise reflection of the data collected from both primary and secondary sources, specifying their levels of error (measurement and sampling error) and their geographic and sectoral coverage.
The guide assumes that the survey findings should include a presentation of the balance of supply and demand (in cases where both aspects are analysed) and of the physical and economic flows of woodfuels (where commercial provision exists), as described in Chapter 5. However, in many cases these objectives may be not included or may be considered unattainable, for example where there is insufficient information on availability.
The conclusions must refer directly and unequivocally to the objectives of the survey and must draw clearly from the data presented. Conclusions deriving from the data but not directly related to the objectives should be presented separately.
Chapter 4 contains recommendations for presenting the results and preparing the final report.
1 Or “saturation”. See definition in Chapter 2.