Innovations for organic Rankine cycle power systems: Current trends and future perspectives
Document type:
Zeitschriftenaufsatz
Author(s):
Wieland, C.; Schifflechner, C.; Braimakis, K.; Kaufmann, F.; Dawo, F.; Karellas, S.; Besagni, G.; Markides, C. N.
Abstract:
Since the early 2000s, organic Rankine cycle (ORC) technology has experienced rapid development and market
uptake. More than 4.5 GW of total ORC power plant capacity has been installed since then. Due to its flexibility,
suitability for small- to medium-scale installations, its applicability to low- to medium-temperature heat sources,
and compact design, ORC technology is already considered as state-of-the-art. However, to further increase the
technical and economic potential of this technology, significant research is needed to further improve efficiency
and other key performance indicators, as well as to address environmental and safety aspects. Therefore, it is
important to research new technologies and to foster innovations for improving performance; but it is of similar
importance to resolve operational challenges with applied research that focuses closer to the market, and the
technology provider and user needs. This vision article outlines the current state-of-the-art and presents current
research trends. Parts of this article summarize the research progress reported at the 6th International Seminar
on ORC Power Systems (ORC2021) and accompanies the associated special issue published following this event.
The article highlights research trends at the concept level, but also at the component and system levels and,
therefore, provides a holistic overview for the interested reader regarding the current challenges and potential
future research activities in this area. Beyond the variety of cycle concepts in Section 2.1, the different heat
sources and applications in Section 2.2, rotating device and turbomachinery (pumps and expansion devices)
options in Section 2.3, current R&D trends for working fluids are presented in Section 2.4. This editorial concludes
with a more applied perspective on ORC systems, covering process control and a general perspective on
the technology in Section 2.5. With an increasing number of ORC plants operating in the field, their integration
within a wider energy system is also of increasing importance, and this is addressed in Section 2.6. All prior
elements are levers toward the grand challenges in ORC technology: increasing efficiency, reducing investment
costs, as well as increasing sustainability, environmental performance, and system compactness.