Electricity from solar cells is not always a good fit for the power grid. It is either not needed at certain times or is too weak, for example, to charge an electric car. The direct integration of an ultracapacitor could be a solution here.https://www.notebookcheck.net/Solar-cell-combined-with-supercapacitor-provides-power-24-7.941388.0.html
IMHO: the obvious application would be to 'flatten out' the intermittent output of the solar cells during periods of passing clouds & partial shade.
Was this article machine translated from Korean? Sentences seem disjointed one from another.