Analysis of the availability and use of the biomass resource is crucial if biomass energy is to be used on a sustainable basis. Detailed biomass energy flow charts for Kenya and Zimbabwe have been produced. Both of these flow charts took an average of Ig months to complete because of the difficulty in obtaining and analysing detailed and good quality data. In view of this, we have developed a flexible spreadsheet methodology which applies a common methodology to the drafting of biomass energy flow charts as a useful initial guide to more detailed studies. The FAOSTAT. PC database was chosen as the primary data source as it accounts for forestry and agricultural production in well defined and comparable categories for each country. Users can incorporate their own data energy values, and energy ratios in an attempt to produce more accurate biomass energy how charts than could be drafted from the FAOSTAT. PC database and default settings alone.