This paper presents the findings of a study on decision making models for the analysis of capital-risk investors! preferences on biomass power plants projects. The aim of the work is to improve the support tools for policy makers in the field of renewable energy development. Analytic Network Process (ANP) helps to better understand capital-risk investors preferences towards different kinds of biomass fueled power plants. The results of the research allow public administration to better foresee the investors' reaction to the incentive system, or to modify the incentive system to better drive investors' decisions. Changing the incentive system is seen as major risk by investors. Therefore, public administration must design better and longer-term incentive systems, forecasting market reactions. For that, two scenarios have been designed, one showing a typical decision making process and another proposing an improved decision making scenario. A case study conducted in Italy has revealed that ANP allows understanding how capital-risk investors interpret the situation and make decisions when investing on biomass power plants: the differences between the interests of public administrations's and promoters', how decision making could be influenced by adding new decision criteria, and which case would be ranked best according to the decision models. (C) 2013 Elsevier Ltd. All rights reserved.