Wärtsilä has signed a memorandum of understanding (MoU) with Petrocity to develop a harbour tug design. The prime consideration is to maximise the ecological operational sustainability of the vessel since the environmental demands of the new port are among the most stringent in the world. For this reason, the design will be based on the recently launched Wärtsilä HYTug, which features hybrid propulsion and energy storage using batteries. The Wärtsilä HYTug emphasises environmental sustainability, operational efficiency, and lower fuel consumption than is possible with conventional tug designs. The `first-of-its-kind' fully integrated hybrid power module combines engines, the energy storage system, and power electronics optimised to work together through a newly developed energy management system (EMS). It marks a new frontier in marine hybrid propulsion. The fuel efficiency of this design has the added benefit of reducing exhaust emission levels. Furthermore, when operating in `green' mode, it is unlikely that there will be any visible smoke from the Wärtsilä HYTug since the load is being picked-up by the batteries. At the same time, the noise level of the tug will be notably reduced.