Optimization of Biomass-Powered Organic Rankine Cycle

Abstract

Background

Biomass energy, often referred to as conversion-from-biomass-to-energy, has long been recognised as a renewable source particularly suitable for low- and medium-temperature power generation systems. Biomass resources are abundant and versatile, producing both electricity and heat from agricultural residues, forestry waste, and energy crops. The Organic Rankine Cycle (ORC) has emerged as an effective technology for exploiting such resources, with applications ranging from small-scale decentralised rural electrification to large-scale industrial combined heat and power (CHP) systems. Despite these advantages, biomass-powered ORCs face limitations related to thermodynamic efficiency, economic viability, and environmental sustainability. These challenges are closely linked to factors such as working fluid selection, component design, and system configuration.

Methods

This review synthesises recent advances in optimisation strategies for biomass-powered ORC systems. Emphasis is placed on three major areas:

• Working fluid optimisation – evaluation of fluids and mixtures with lower global warming potential and better thermodynamic performance.


• Component and system design – optimisation of heat exchangers, turbines, and layout for improved exergy efficiency.


• Hybridisation and multi-objective approaches – integration with solar energy, part-load operation analysis, and thermoeconomic methods that simultaneously address performance, cost, and environmental impacts.

Results

The literature indicates that optimised working fluid selection and improved heat exchanger design can enhance system efficiency by approximately 10–20%. Hybrid solar–biomass configurations demonstrate superior flexibility, enhanced efficiency, and reduced carbon emissions compared to stand-alone biomass systems. Moreover, multi-objective optimisation frameworks provide balanced solutions that improve energy and exergy efficiency while reducing the levelised cost of electricity (LCOE). Despite these advances, significant research gaps remain, particularly in the areas of large-scale demonstration, advanced control strategies, and integration with polygeneration systems.

Conclusion

Biomass-powered ORCs have the potential to become cost-effective and sustainable solutions within the global low-carbon energy transition. Achieving this requires systematic optimisation across thermodynamic, economic, and environmental dimensions. With further progress in hybridisation strategies, digitalised control systems, and large-scale validation, optimised biomass-ORC technologies could play a central role in delivering reliable, clean, and efficient energy on both small and large scales.