The aim of this paper is the design of a Solar-Electric Boat for tourists’ transport along the coast, in the rivers, in the lakes. Our idea is to define the project guidelines for the realization of a zero impact boat. This paper illustrates the practical new technologies (naval architecture small craft design, mechanical and electrical design), rational design and engineering approach, safety and reliability methods used in solar boats. In our project, the boat is powered by lithiumion batteries that can be charged at any time by the photovoltaic generator placed on a flat top structure. The project is designed for brief trip around coast, where the public transport becomes very polluting during summer. Starting from the consideration that this boat is used during sunny weather, it is possible to know the boat’s energy demand and proceed with the design of a suitable electric boat and of the energy storage/management system. It is also proposed an innovative management of charge/discharge of the batteries. With this management, we have optimized the use and prolonged the time of life of the batteries during the navigation and the control of the real autonomy of it.