The results of the evaluations of the roof MaReCo are shown in figure 6. These values are thus the angular dependence of the reflector exclusively, since the influence from the Teflon and the glazing are deducted, as earlier described. The measurements show good agreement for both methods for low angles of incidence. For high angle of incidence, when the irradiance is low, the cosine dependence shows better agreement with outdoor measurements than diode compensated data.

An equal relation between the indoor and outdoor measurements of the solar hybrid window was found for the roof MaReCo. This result gives another indication of that the
method is working satisfactory and that the simulator can be used for characterisation of concentrating collectors. However, at higher incidence angles, the agreement is not as good as for lower angles, suggesting that the method still needs further improvements.

Discussion

The results of incidence angular dependence from outdoor and indoor measurements show that the agreement is good at lower incidence angles. At higher incidence angles, the correspondence is less accurate. There are possibilities to improve the method further. By adding more photodiodes to the array, the accuracy of the measured total irradiance would be better. Improvements of the reflectors of the solar simulator, to obtain a more even light field, are also possible. An explanation for the lower correspondence at higher incidence angles could be that the active test area is smaller and that the power involved is lower.