Much discussion of technology transfer and the adoption of renewable energy innovations overlooks the importance of social acceptance. Using mainly qualitative analytical techniques, empirical evidence was obtained from the experiences of those involved in solar water heaters in Mexico City (e.g. technicians, industry representatives, local government officials, community representatives/end users) in order to explain social acceptance of these renewable energy innovations. In particular, this paper evaluates Rogers' [2005. Diffusion of Innovations. Free Press, New York.] technology adoption model (using an "active" definition of social acceptance), which claims that adoption comes about through a decision-making process occurring in stages-knowledge, persuasion, implementation and confirmation and can be traced to a number of factors such as relative advantage, complexity, and triability. This paper argues that while Rogers' technology adoption model is a useful tool to explain social acceptance, this approach needs to be revised to adequately reflect the effects of technology cooperation, an integral part of technology adoption. Furthermore, this paper asserts that those forms of technology cooperation in which active participants are from various sectors and interact continuously throughout the process is most effective in eliciting social acceptance of renewable energy innovations. (c) 2006 Elsevier Ltd. All rights reserved.