The JOULES project (1. June 2013 - 31. Mai 2017) is accepting the future challenges for the European Maritime Industry to siginificantly reduce energy consumption, emission of climate gases and other harmful emissions to air. The simulation of the vessels energy grid in early design stage has been identified to be a key solution in this respect. The impact on ship design with respect to integration of proven and innovative technologies in vessels energy grid will be assessed from an economical point of view. In addition, the environmental impacts taking into account the cradle to grave concept will be evaluated in depth. Thus a new holistic approach on ship design for two future scenarios (2025 and 2050) will be realized, lifting the potential of the Euroopean Maritime Industry to contribute to a more sustainable future.