Development of a novel bi-axial solar concentrator for biomass assisted gasification

Integrating solar energy with biomass gasification offers a promising pathway toward sustainable and more efficient energy production. Concentrated Solar Power (CSP) can serve as an external heat source for high-temperature biomass gasification, offering advantages such as a higher lower heating value (LHV) and an improved biomass-to-gas conversion ratio. Such high temperatures can be achieved only through high-concentration, bi-axial tracking CSP systems, which typically require large, unobstructed ground areas for installation. In addition, precise tracking is required and the dimensions of the optical system (mirror or lens) increases. In this context, the linear Fresnel reflector stands out due to its flat, narrow mirrors, which are less susceptible to wind and atmospheric disturbances. It also exhibits a higher ground coverage efficiency, thereby reducing the space required for installation. This paper deals with the performance analysis of a biaxial Fresnel concentrator using the ray-tracing simulation software Tonatiuh, with the aim of evaluating different mirrors linkage, which can make use of a lower number of actuator than moving each mirror with a couple of actuators. Several tracking strategies were compared with an ideal tracking from the point of view of the collected solar energy. Simulations were carried out in several representative days along the year to discuss the better mirror field configuration. Different receiver shapes were also tested as part of this analysis. A simplified mirror aiming method resulted in comparable optical efficiency to an ideal system equipped with individual mirror movement. In addition, heat production along the day resulted to be more constant and hence more suited to the needs of a thermal process such biomass gasification.