Advanced dynamic positioning (DP) vessels can now meet critical safety regulations while gaining operational flexibility, efficiency and cost savings through new design and monitoring methods. More and more operators are asking their drilling contractors to operate their DP units in closed-bus mode, in order to save on fuel and maintenance costs and to reduce the environmental footprint. It also enables a significant reduction in engine hours, with less wear and tear on the engine, and expanded windows for maintenance in a cold engine room. Dynamic positioning operations are strictly regulated, as loss of position can have dire consequences. Loss of power is a main risk, and complete redundant design including generators and thrusters has been required.