Assement of Biomass potential for electricity Generation in Nicaragua: GIS as a decision support tool for investmemts in Bioenergy Carlos Zelaya Martinez and Pita Verweij Dept. of Science, Technology and Society Utrecht University The development of sources of renewable energy is gaining momentum. As a result of the climate negotiations of CoP-6 in The Hague and Bonn, it is expected that the Clean Development Mechanism will lead to growing foreign investments into renewable energy systems of developing countries. For Nicaragua, energy derived from biomass represents an attractive option. Residues from agricultural crops and the forestry sector and biomass from dedicated energy plantations can be used. The objective of the paper is to assess the biomass potential at national level for commercial generation of electricity in Nicaragua. The allocation of land for energy crops should be done efficiently because even in Nicaragua, land is increasingly becoming a scarce resource. Competition with food production should be avoided and the risk of unintended conversion of remaining natural forests should be minimised by careful planning at proper locations. Planning of optimal location and size of both biomass power plants and corresponding energy plantations is usually more complex than planning of fossil fuel power plants, amongst others because of the following factors: As a result of the low energy density of biomass, its transportation costs are relatively high. This favours smaller biomass plants, whereas larger plants tend to be more efficient. Economies of scale are therefore an important issue to consider. Due to variation in socio-economic and biophysical conditions, the quantity and cost of energy crop supply may show considerable geographic variation. The generation of an agro-ecological zonation map constitutes the first phase in the process of developing a spatial model of biomass potential for optimised allocation as bioenergy. The methodology of agro-ecological zonation (AEZ) as developed by FAO (1978) was taken as a basis. Most existing AEZ were designed for the production of food crops and livestock. The paper describes modifications to the existing approach to accommodate for the production of woody crops that are related to different land use requirements. Besides the normal Land Utilisation Types (LUTs) related to food production, different types of forest plantations are distinguished. Shade coffee plantations and agroforestry systems are examples of LUTs that can related to a limited wood supply. A nation-wide database was built up in GIS, comprising information on topography, geology, climate, relief, soils, land cover and infrastructure at a scale of 1:250,000. By matching the climatic, edaphic and topographic requirements of each LUT with relevant attribute layers, an agro-ecological zonation map was elaborated. For each AEZ unit, composed of single or multiple LUTs, biomass volume was calculated on the basis of both recommended and actual land use, after subtracting natural forest cover. The resulting map of biomass potential was used to identify promising areas, by combining it with information on proximity to actual road infrastructure. In this way, regions of interest were selected: future studies can zoom in at these regions and more detailed models including socio-economic variables can be developed, in order to arrive at optimised locations for both biomass plants and energy plantations.