Compléter Watertight boilers and Hydrogen as fuel.Version en ligne Fill the gaps. par Yanet Rivero 1 Watertight : Modern work in a way , with taking place in a completely closed where it never has contact with the in the room . Hydrogen as : is a gas that represents the future of fuels , wheter used directly in or as the fuel for hydrogen that generate electricity . It is still in the process of due to difficulties in it from water processes and the need to create a new .