The Hidrocat Project – An all electric ship with photovoltaic panels and hydrogen fuel cells

The HIDROCAT is an all electric small ship that uses energy from three sources, namely: the hydrogen stored on board via fuel cells, the solar energy and energy stored on batteries. In this sense, it is a hybrid propulsion system composed of two electric motors, a system of lithium batteries, a hydrogen fuel cell and photovoltaic cells. A control unit does the management of the energy fluxes. The objective is to maximize the use of solar energy, therefore the system of batteries is important to store the converted solar energy when it is not immediately used by the motors. The hydrogen fuel cell guarantees that energy is available on board at the expense of a relatively small weight when the solar irradiation is insufficient due to intensive use of the motors for long periods, or when the solar irradiation is low.
The concept described above is implemented in a preliminary project of a tourist catamaran and it is demonstrated that not only the operational requirements are accomplished by the project, but also that a demonstration project can be implemented with the existing technology. The preliminary design includes the hull bodylines, propulsion system, general arrangement, weight estimate, vessel speed, and autonomies. Several scenarios of operation are investigated for the Alqueva Lake in Portugal and it is concluded that the Hidrocat satisfies the design requirements in terms of autonomies. Furthermore, it is concluded that if the operational scenario is not very demanding, during summer the vessel may carry out its mission using solar energy only.