Scientists at The Australian National University (ANU) have set a world record for efficiency for a solar thermal dish generating steam that could be used for power stations.
The team designed and built a new receiver for the solar concentrator dish at ANU, halving losses and achieving a 97 per cent conversion of sunlight into steam.
The breakthrough could lead to the generation of cheaper base-load electricity from renewable energy and help lower carbon emissions which cause global warming.
Ref: Development of a higher-efficiency tubular cavity receiver for direct steam generation on a dish concentrator. AIP | Conference Proceedings (2016) | DOI: 10.1063/1.4949081
An integrated model for an axisymmetric helical-coil tubular cavity receiver is presented, incorporating optical ray-tracing for incident solar flux, radiosity analysis for thermal emissions, computational fluid dynamics for external convection, and a one-dimensional hydrodynamic model for internal flow-boiling of water. A receiver efficiency of 98.7% is calculated, for an inlet/outlet temperature range of 60–500 °C, which is the ratio of fluid heating to receiver incident irradiance. The high-efficiency design makes effective use of non-uniform flux in its non-isothermal layout, matching lower temperature regions to areas of lower flux. Full-scale testing of the design will occur in late 2015.