As we need adapted software to calculate the solar flux concentration through a tower-heliostat field system, an overview of computer codes was performed, detailing their features, strengths and weaknesses. For this a questionnaire was sent to developers or heavy users of codes that are currently used in the concentrated solar power (CSP) community. Answers to this questionnaire make it possible to determine which tool is relevant depending on the objectives of the simulation. Modeling tools for central receiver systems (CRS) can be divided into two main categories, corresponding to two kinds of problems: on one hand those dedicated to system optimization and on the other hand those designed to detailed analysis of the optical performances. A bibliographic study on first generation and developing codes complements this overview of tools that may be interesting for CSP research or industry.

The CNRS-Promes dish∕Stirling system was erected in Jun. 2004 as the last of three country reference units built in the “Envirodish” project. It represents the latest development step of the EuroDish system with many improved components. With a measured peak of 11kW electrical output power, it is also the best performing system so far. The measurement campaign to determine the optical and thermodynamic efficiency of the system is presented. The optical quality of the concentrator and the energy input to the power conversion unit was measured with a classical flux-mapping system using a Lambertian target and a charge coupled device camera system. An efficiency of the concentrator including the intercept losses of 74.4% could be defined for this particular system. For the thermodynamic analysis all the data necessary for a complete energy balance around the Stirling engine were measured or approximated by calculations. For the given ambient conditions during the tests, a Stirling engine efficiency of 39.4% could be measured. The overall efficiency for the conversion of solar to electric energy was 22.5%.

No abstract