Wood Energy Data

Data categories - Data availability - Data collection - RWEDP activities - Further reading - Other issues in wood energy

One of the main reasons usually given for the little attention paid to wood energy by planners and policy-makers, is the lack of data. In fact, a considerable amount of data may exist, but because wood energy relates to many different fields, data should come from many different agencies. This means that data are usually not available at one place, and definitions, terminology and units of data are not unambiguous, which complicates analysis. At national level, no wood energy agencies exist that collect and publish data for the whole range of wood energy, i.e. consumption, conversion, distribution, resources and related economic, social and environmental aspects.

Data Categories

Wood energy data can be grouped in five categories:

Utilization: consumption patterns for different woodfuel consuming sectors, e.g. households, institutions (e.g. schools, hospitals, army camps), industries and services (e.g. restaurants, food vendors). An important sector is the informal one, i.e. foodvendors, eateries and industries that are outside the formal economy, but which may use substantial amounts of wood energy. For all sectors, data should distinguish fuels and end-use activities, such as cooking, heating, process heat and steam generation. Households preferably should be disaggregated into rural and urban households, as well as income groups. For industries, data should consider types of technology and industry (e.g. food processing, brick-making).

Resources: wood resources can be distinguished into tree resources on land and recovered wood. Tree resources refers to wood growing on land, and data should include different land use types (e.g. crop fields, forest), considering wood production systems (e.g. plantation, agro-forestry) and management systems (e.g. state, private, community). Recovered wood refers to residues from wood processing activities like logging, saw milling and furniture making. Apart from wood resources, also crop and animal residues should be included.

Technology: end-use devices (e.g. stoves, ovens) and conversion equipment (e.g. charcoal kilns, briquetting machines). Data should include technical aspects (efficiency, capacity, method of operation, lifetime), economic aspects (prices, investment costs), environmental aspects (emissions) and social aspects (employment, gender).

Woodfuel flows: conversion, distribution and trade of woodfuels. Data should cover sources of woodfuels, the distribution network (producers, transporters, wholesalers, retailers), conversion technology applied, social factors (employment, gender) and economic factors (costs, prices at different stages).

Socio-economic factors: aspects which are not always directly related to wood energy, but information is required for deeper analysis and forecasting. Data includes population, economy, income, and social aspects, such as health hazards of using and producing woodfuels. Gender specific data include roles of man and women in woodfuel production, collection and use, time spent on activities, and job opportunities for women.

Data Availability

For most Asian countries, data on total wood energy consumption are available, but supply data are limited. Available data on total consumption refer mainly to households, while consumption data for other sectors such as industries and services is often missing. However, a considerable amount of research data is available for different types of industries. Only very few countries conduct regular nation-wide (wood) energy consumption surveys. Other countries may extrapolate data from project-level studies to country level, or use estimates for woodfuel consumption per capita, assuming a linear relationship between woodfuel consumption and population.

Data on woodfuel resources are basically limited to forest resources. However, data on wood resources from forests generally only consider stem wood, ignoring smaller branches and twigs, which are important woodfuel sources. A lot of woodfuels come from non-forest areas, such as crop fields and village land but hardly any data are available for woodfuel resources from these areas, apart from a major study in Pakistan and estimates for some other countries. Many analytical studies on available woodfuel supply consider only forest resources, ignoring the substantial supply from other areas and residues from wood processing, and thus severely underestimating the total woodfuel supply.

For technologies and woodfuel flows, data are scattered and limited. For cookstoves and charcoal production, technical data like efficiencies are available, but social, economical and environmental data are limited. For charcoal production generally no data are collected for the total amount of production but this is usually derived from consumption data using an average efficiency figure. For other aspects such as transportation, employment and income generation information is available only for some selected countries.

Socio-economic data such as population, economy and income are generally available from national statistical offices that publish all sorts of data and often conduct household expenditure surveys. Data on social and gender aspects are limited and only available from some project studies.

Data Collection

Most wood energy data can only be obtained from surveys, but a lot of data may already be available from previous surveys, so secondary data collection, i.e. compiling data from existing publications, studies, statistics and databases, is very important. Energy, forestry, agricultural, rural development, statistical and other agencies all may have data relevant to wood energy.

Both for wood and conventional energy, detailed data on consumption can only be obtained by conducting surveys. For conventional fuels this is relatively easy because consumption can be measured from expenditure and fuel price, as is sometimes done for household expenditure surveys. For wood energy this is more complicated, because it comes in non-standard units such as bundles and bags, and a large amount is collected and used for free, which means that physical measurements should be conducted. Furthermore, the density of woodfuels depends on wood species and moisture content, so conversion between volume units and mass units is a source of inaccuracies.

Several survey methods exist, such as sample surveys using questionnaires, interviewing key informants and groups, field measurements and RRA. The choice of method would, among others, depend on the type of data to be collected, purpose of the data, and budget and time available.

RWEDP activities

RWEDP compiles and selects data from secondary sources on all aspects of wood energy for its 16 member countries, in order to analyze past and current trends, and to make these data available to interested users. On woodfuel flows, RWEDP has supported several studies in different countries, which generated a valuable amount of information. RWEDP published a special issue of Wood Energy News with selected data, and an overview of available wood energy data for all 16 member countries. For the 'Regional Study on Wood Energy Today and Tomorrow', best estimates for wood energy consumption and estimates for potential wood energy supply were made based on available data. Furthermore, RWEDP has developed a wood energy database that contains data on several wood energy aspects, and is currently working on a database that will make these data available on the Internet site.

Wood Energy Data

Data Categories

Data Availability

Data Collection

RWEDP activities

Further reading: