The main objective of this paper is the presentation of a theoretical and quantitative study of the power requirements that any port considering to install and develop shore to ship connection systems must consider. Particularly, the current study focuses these requirements for cruise ship ports and their terminals. This paper provides theoretical and quantitative tools and ideas that can be used to estimate main design parameters such as frequency, voltage and power for high voltage shore connections. Some models and equations are developed aiming to be able to estimate, with acceptable quality, cruise ship’s power demand for hoteling services at port. On the other hand, this article is intended to assess ship's air pollution impact populated harbour areas to decide whether alternative power supply measures are feasible. Finally, the assessment model is applied at Barcelona's cruise piers and case study is discussed. As a result of that, a daily power demand curve and the consequent air pollution study at the most crowded situation in this port are obtained.