Indoor System Testing Based on ISO-9459-5 Using a Dynamic Solar Simulator
Abstract
In order to enable indoor testing of solar thermal systems the international standard ISO 9459-5:2007 has to be adapted to indoor test conditions. If a system test is performed with the Dynamic System Test Method (DST-method) according to ISO 9459-5:2007, the measured data are evaluated by using the InSitu Software ISS (Spirkl, 1997). The characteristic system parameters derived by this process are used for the long term performance prediction (LTP) to determine the solar fraction fsol of the system. As a basis for performing indoor tests it is necessary to define appropriate artificial radiation profiles. To do this, artificially generated “measured data”, so called “synthetic data” were used. This synthetic data was generated by means of TRNSYS simulations and evaluated with the InSitu Software ISS according to the procedure specified in ISO 9459-5:2007. Using different sets of data as input data for the TRNSYS model, different system answers and thus different LTPs were obtained. This effect is well known from outdoor measurements with the same system under different weather conditions. According to Naron and Ree (1999) the observed maximum deviation in the solar fraction due to different weather conditions is ± 5 % relative. This paper describes the newly developed dynamic solar simulator and presents an indoor system test procedure on the basis of ISO 9459-5: 2007.