Investments in renewable energy (RE) technologies are regarded with increasing interest as an effective means to stimulate growth and accelerate the recovery from the recent financial crisis. Yet, despite their appeal, and the numerous policies implemented to promote these technologies, the diffusion of RE projects remains somehow below expectations. This limited penetration is also due to a lack of appropriate financing and to a certain reluctance to invest in these technologies. In order to shed light on this phenomenon, in this paper we examine the decision making process underlying investments in RE technologies. We propose and test a conceptual model that examines the structural and behavioural factors affecting the investors [...]