Seawater Air Conditioning (SWAC) is a sustainable alternative for tropical islands. Despite its potential, adoption has been limited throughout the world. There is a need to understand SWAC adoption potential in the Caribbean and to identify the actions and policies that could favor its diffusion. We develop a system dynamics simulation model for SWAC adoption, and use it to simulate scenarios and incentives for SWAC in Jamaica. We found that SWAC adoption is mainly limited by the threshold capacity necessary for the first installation.