In order to realize the benefits of the digitalization and automation of production and processing systems, users first need to increase the level of integration, controllability and monitoring capabilities of each component applied. Therefore, digital twins turn out to be a highly important asset not only for designing greenfield applications, but also for improving brownfield machines. Up to now, digital twins were barely implemented to their full potential throughout the design, integration, and operation phases of production and processing equipment. Based on the experiences gained during the development of a subsea valve actuator, this paper highlights the importance of the digital twin to speed up the engineering and qualification of an innovative mechatronic system, reducing not only the time to market, but also increasing quality and allowing a fast reaction to the experience of the users. As a perspective, the paper shows how an accurate digital twin is a key to successful integration of a new component into complex machines. This includes the entire product lifecycle, from the conceptual work of a system and its virtual commissioning up to remote cloud-based monitoring systems. This paper finishes with an overview of some of the challenges which need to be resolved by the cooperation among different players in order to allow a wide and deep application of Digital Twin in the energy sector industry.