One of the emerging schemes for power production and waste heat recovery applications is the organic Rankine cycle (ORC). This energy conversion scheme illustrates considerable potential to be increasingly employed for power generation in the future. Furthermore, ORC-based systems can be utilised in many industrial processes to meet carbon footprint reduction goals. For example, the ORC scheme can be used in stationary power plants that contain a large number of unused effective energy streams or in many highly intensive industries that show potential for energy recovery.

Various applications can be defined for the ORC in the transportation sector to save fuel by utilising waste heat from engines. The ORC is also practical in energy harvesting from low and high enthalpy streams of renewable sources, namely, solar or geothermal. The ORC scheme is an approved technology for large power plants at present. However, there are some technological items and challenges which are not completely addressed. For example, the ORC needs to be improved from an economic perspective to increase its acceptance in the market. In terms of small or micro-scale power generation applications, the ORC is not thoroughly developed for presentation to the market.

In this Special Issue, researchers from all over the world are kindly invited to submit their quality articles with regard to defining new applications of the ORC, improving cycle performance, selecting working fluids, designing and optimising used components, and developing advanced operation strategies. Original research and review articles are both welcome.

Potential topics include but are not limited to the following:

• Waste heat recovery applications
• Applications of ORC power plants for electricity supply to the building sector
• Advanced ORC based thermodynamic cycles
• Combined heat and power generation
• Modelling and control of hybrid systems based on Organic Rankine Cycle
• 4 E (Energy, Exergy, Economic and Environmental) analyses of hybrid systems based on the organic Rankine cycle
• Optimisation of the performance of hybrid systems based on organic Rankine cycle
• Eco-friendly organic fluids and mixtures.
• Expanders for waste-heat recovery applications
• Application and optimisation of effective heat exchangers.
• Renewable energy development and waste heat recovery based on the organic Rankine cycle
• Experiments on micro-ORC generators
• New organic fluids for power generation
• New integrations of ORC with other energy systems
• Environmental impact assessment of ORC based energy systems